/* ==========================================================================
   信息科技赛考校队 · 站点样式
   明亮青春风：白底 + 天空蓝/葡萄紫/蜜黄/薄荷绿 的糖果色板，
   区块编号 01/02/03 走渐变，标题区是「左标签列 + 右内容」两栏，
   卡片带彩色描边与彩色投影，悬停轻轻上浮。
   ========================================================================== */

/* ---------- 设计变量 ---------- */
:root {
  --bg: #ffffff;
  --bg-2: #f4f9ff;        /* 交替区块：极浅天蓝 */
  --bg-3: #ffffff;        /* 卡片 */
  --bg-4: #f8fbff;        /* 卡片悬停 */
  --line: #e2ecf9;
  --line-2: #eff5fc;

  --fg: #16233a;
  --fg-2: #46587a;
  --fg-3: #6f84a6;
  --fg-4: #9fb0c9;

  /* 青春色板 */
  --cy: #0ea5e9;          /* 天空蓝 */
  --bl: #3b82f6;
  --vi: #8b5cf6;          /* 葡萄紫 */
  --pk: #ec4899;          /* 桃红 */
  --am: #f59e0b;          /* 蜜黄 */
  --em: #10b981;          /* 薄荷绿 */
  --ro: #fb7185;          /* 珊瑚 */

  --cy-soft: #e6f6ff;
  --bl-soft: #e8f0ff;
  --vi-soft: #f1ebff;
  --pk-soft: #fdeaf4;
  --am-soft: #fff4dc;
  --em-soft: #e2fbf0;
  --ro-soft: #ffecef;

  --grad: linear-gradient(120deg, #38bdf8, #6366f1 52%, #a855f7);
  --grad-warm: linear-gradient(120deg, #fbbf24, #fb7185 52%, #a855f7);

  --r-sm: 12px;
  --r: 16px;
  --r-lg: 22px;
  --r-xl: 28px;

  --sh-sm: 0 2px 6px rgba(22, 35, 58, .05), 0 8px 24px rgba(22, 35, 58, .05);
  --sh: 0 10px 30px rgba(22, 35, 58, .08), 0 2px 8px rgba(22, 35, 58, .04);
  --sh-lg: 0 22px 50px rgba(22, 35, 58, .12);
  --sh-cy: 0 14px 34px rgba(14, 165, 233, .18);
  --sh-vi: 0 14px 34px rgba(139, 92, 246, .18);

  --wrap: 1400px;
  --wrap-mid: 1100px;
  --wrap-narrow: 760px;

  /* 旧变量名别名：页面里还有内联样式与代码窗口规则在用 */
  --ink: #16233a;
  --ink-2: #46587a;
  --ink-3: #6f84a6;
  --ink-4: #9fb0c9;
  --bg-soft: #f4f9ff;
  --bg-tint: #f6fbff;
  --bg-tint-2: #f2f8ff;
  --brand: #0ea5e9;
  --brand-d: #0284c7;
  --brand-l: #38bdf8;
  --brand-soft: #e6f6ff;
  --brand-line: #bae6fd;
  --violet: #8b5cf6;
  --violet-soft: #f1ebff;
  --teal: #10b981;
  --teal-soft: #e2fbf0;
  --amber: #f59e0b;
  --amber-soft: #fff4dc;
  --rose: #fb7185;
  --rose-soft: #ffecef;
  --green: #10b981;
  --green-soft: #e2fbf0;

  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "HarmonyOS Sans SC", "Hiragino Sans GB", "Source Han Sans SC",
    "Noto Sans CJK SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --mono: "SF Mono", "JetBrains Mono", "Cascadia Mono", Consolas, "Courier New", monospace;
}

/* ---------- 基础 ---------- */
*, *::before, *::after { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: 96px;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.75;
  letter-spacing: .01em;
  -webkit-font-smoothing: antialiased;
  /* 页面顶部与左侧各一团彩色柔光，明快但不抢内容 */
  background-image:
    radial-gradient(760px 420px at 8% -6%, rgba(56, 189, 248, .16), transparent 62%),
    radial-gradient(680px 380px at 96% 2%, rgba(168, 85, 247, .13), transparent 60%),
    radial-gradient(560px 320px at 50% 108%, rgba(16, 185, 129, .1), transparent 65%);
  background-repeat: no-repeat;
}

h1, h2, h3, h4 {
  margin: 0 0 .5em;
  color: var(--fg);
  line-height: 1.22;
  letter-spacing: -.015em;
  font-weight: 800;
  text-wrap: balance;
}
h1 { font-size: clamp(2.2rem, 4.4vw, 3.5rem); font-weight: 850; }
h2 { font-size: clamp(1.5rem, 2.6vw, 2.15rem); }
h3 { font-size: clamp(1.06rem, 1.3vw, 1.2rem); }
p { margin: 0 0 1em; }
p:last-child { margin-bottom: 0; }

a { color: var(--brand-d); text-decoration: none; transition: color .16s ease; }
a:hover { color: var(--vi); }
strong, b { font-weight: 700; color: var(--fg); }
em { font-style: normal; color: var(--brand-d); }

ul, ol { margin: 0 0 1em; padding-left: 1.3em; }
li { margin: .35em 0; }

img, svg { max-width: 100%; }
code {
  font-family: var(--mono);
  font-size: .88em;
  padding: 2px 7px;
  border-radius: 6px;
  background: var(--cy-soft);
  color: #0369a1;
}
hr { border: 0; border-top: 1px solid var(--line); margin: 2.5em 0; }

::selection { background: rgba(56, 189, 248, .28); color: var(--fg); }

:focus-visible {
  outline: 3px solid rgba(56, 189, 248, .55);
  outline-offset: 3px;
  border-radius: 6px;
}

.skip {
  position: absolute;
  left: -9999px;
  top: 0;
  z-index: 200;
  background: var(--grad);
  color: #fff;
  padding: 10px 18px;
  border-radius: 0 0 12px 0;
  font-weight: 700;
}
.skip:focus { left: 0; }

/* ---------- 容器与网格 ---------- */
.wrap { width: 100%; max-width: var(--wrap); margin-inline: auto; padding-inline: 36px; }
.wrap--mid { max-width: var(--wrap-mid); }
.wrap--narrow { max-width: var(--wrap-narrow); }

.grid { display: grid; gap: 22px; }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

.split {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 360px;
  gap: 56px;
  align-items: start;
}
/* 侧栏在左：三处 rail（首页精选问答、课程问答、安装问答）的 HTML 都是
   .rail__side 在前，列定义必须与之对应，否则问答列表会被塞进窄列 */
.rail {
  display: grid;
  grid-template-columns: 320px minmax(0, 1fr);
  gap: 48px;
  align-items: start;
}
.rail__side { position: sticky; top: 104px; }
.rail__side h2 { font-size: clamp(1.35rem, 2vw, 1.72rem); }
.doc {
  display: grid;
  grid-template-columns: 236px minmax(0, 1fr);
  gap: 48px;
  align-items: start;
  /* 问答库是全文字页，整体收窄居中，避免长行读起来累 */
  max-width: 1180px;
  margin-inline: auto;
}

.mt-3 { margin-top: 24px; }
.mt-4 { margin-top: 36px; }
.mt-5 { margin-top: 52px; }

/* ---------- 区块 ---------- */
.section {
  padding: 96px 0;
  counter-increment: sec;
  position: relative;
}
/* 区块之间用一条渐变细线分隔，比灰线更青春一点 */
.section + .section::before {
  content: "";
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(56, 189, 248, .45) 22%, rgba(168, 85, 247, .4) 62%, transparent);
}
.section--soft { background: var(--bg-2); }
.section--tight { padding: 64px 0; }
main { counter-reset: sec; }

/* 区块标题：左标签列 + 右标题正文
   右栏占满剩余宽度（正文不再限宽），否则大屏上标题右侧会空出一大片 */
.sec-head {
  display: grid;
  grid-template-columns: 200px minmax(0, 1fr);
  gap: 16px 40px;
  align-items: start;
  margin-bottom: 48px;
}
.sec-head > p {
  grid-column: 2;
  max-width: none;
  color: var(--fg-2);
  font-size: 1.02rem;
}
.sec-head h2 { margin-bottom: 0; }

.sec-label {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--mono);
  font-size: .74rem;
  font-weight: 700;
  letter-spacing: .16em;
  color: var(--brand-d);
  text-transform: uppercase;
  white-space: nowrap;
}
/* 编号由计数器生成，新增区块不用手改；每个区块的编号换一种糖果色 */
.sec-label::before {
  counter-increment: sub;
  content: counter(sec, decimal-leading-zero);
  font-size: 1.6rem;
  font-weight: 850;
  letter-spacing: 0;
  line-height: 1;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
/* 注意：background 简写会把 background-clip 重置回 border-box，
   所以换色时要重新声明一次 clip，否则编号会变成实心色块 */
.section:nth-of-type(3n+2) .sec-label::before {
  background: linear-gradient(120deg, #fbbf24, #fb7185);
  -webkit-background-clip: text;
  background-clip: text;
}
.section:nth-of-type(3n+3) .sec-label::before {
  background: linear-gradient(120deg, #34d399, #0ea5e9);
  -webkit-background-clip: text;
  background-clip: text;
}
.sec-label .ico { width: 15px; height: 15px; color: var(--fg-4); }
.sec-head .sec-label { margin-bottom: 0; padding-top: 6px; }
/* 全站区块标题统一成「左标签列 + 右标题正文」，不再混用居中样式 */
.sec-label--teal { color: #059669; }
.sec-label--violet { color: #7c3aed; }
.sec-label--amber { color: #d97706; }

/* ---------- 图标 ---------- */
.sprite { position: absolute; width: 0; height: 0; overflow: hidden; }
.ico {
  width: 1em; height: 1em;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.75;
  stroke-linecap: round;
  stroke-linejoin: round;
  flex: 0 0 auto;
  vertical-align: -0.13em;
}
.ic-brand { background: var(--bl-soft); color: #2563eb; }
.ic-violet { background: var(--vi-soft); color: #7c3aed; }
.ic-teal { background: var(--em-soft); color: #059669; }
.ic-amber { background: var(--am-soft); color: #d97706; }
.ic-rose { background: var(--ro-soft); color: #e11d48; }
.ic-green { background: var(--em-soft); color: #059669; }

/* ---------- 顶栏 ---------- */
.topbar {
  position: sticky;
  top: 0;
  z-index: 80;
  background: rgba(255, 255, 255, .82);
  backdrop-filter: saturate(180%) blur(16px);
  border-bottom: 1px solid var(--line);
}
.topbar__in {
  display: flex;
  align-items: center;
  gap: 28px;
  height: 72px;
}

.brand { display: flex; align-items: center; gap: 11px; color: var(--fg); }
.brand:hover { color: var(--fg); }
.brand__mark {
  width: 40px; height: 40px;
  border-radius: 13px;
  background: var(--grad);
  color: #fff;
  display: grid;
  place-items: center;
  font-family: var(--mono);
  font-size: .76rem;
  font-weight: 800;
  letter-spacing: .02em;
  box-shadow: 0 8px 20px rgba(56, 189, 248, .35);
  flex: 0 0 auto;
}
.brand__txt { display: flex; flex-direction: column; line-height: 1.25; }
.brand__name { font-size: 1rem; font-weight: 800; color: var(--fg); letter-spacing: -.01em; }
.brand__sub {
  font-family: var(--mono);
  font-size: .66rem;
  letter-spacing: .08em;
  color: var(--fg-4);
}

.nav { display: flex; align-items: center; gap: 4px; margin-left: auto; }
.nav a {
  padding: 9px 13px;
  border-radius: 10px;
  font-size: .92rem;
  font-weight: 650;
  color: var(--fg-2);
}
.nav a:hover { color: var(--brand-d); background: var(--cy-soft); }
.nav__cta {
  margin-left: 10px;
  background: var(--grad) !important;
  color: #fff !important;
  font-weight: 750 !important;
  box-shadow: 0 8px 22px rgba(56, 189, 248, .35);
}
.nav__cta:hover { filter: brightness(1.06); color: #fff !important; }

.nav-toggle {
  display: none;
  margin-left: auto;
  width: 42px; height: 42px;
  border-radius: 12px;
  border: 1px solid var(--line);
  background: #fff;
  color: var(--fg);
  cursor: pointer;
  place-items: center;
}
.nav-toggle .ico { width: 20px; height: 20px; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 24px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: #fff;
  color: var(--fg);
  font-family: inherit;
  font-size: .96rem;
  font-weight: 700;
  line-height: 1.2;
  cursor: pointer;
  transition: background .16s ease, border-color .16s ease, color .16s ease,
              box-shadow .16s ease, transform .16s ease, filter .16s ease;
}
.btn:hover {
  border-color: var(--brand-line);
  color: var(--brand-d);
  box-shadow: var(--sh);
  transform: translateY(-2px);
  text-decoration: none;
}
.btn--primary {
  background: var(--grad);
  border-color: transparent;
  color: #fff;
  font-weight: 800;
  box-shadow: 0 12px 28px rgba(56, 189, 248, .32);
}
.btn--primary:hover {
  color: #fff;
  filter: brightness(1.06);
  box-shadow: 0 16px 36px rgba(99, 102, 241, .38);
}
.btn--ghost { background: #fff; border-color: var(--brand-line); color: var(--brand-d); }
.btn--ghost:hover { background: var(--cy-soft); border-color: var(--brand); }
.btn--soft { background: var(--cy-soft); border-color: transparent; color: #0284c7; }
.btn--soft:hover { background: #d8efff; color: #0369a1; }
.btn--onDark { background: rgba(255, 255, 255, .9); border-color: transparent; color: var(--brand-d); }
.btn--onDark:hover { background: #fff; color: var(--brand-d); }
.btn--ghostDark { background: transparent; border-color: rgba(255, 255, 255, .6); color: #fff; }
.btn--ghostDark:hover { background: rgba(255, 255, 255, .2); color: #fff; }
.btn--sm { padding: 9px 17px; font-size: .88rem; border-radius: 11px; }
.btn--block { width: 100%; }

/* ---------- 首屏 ---------- */
.hero { position: relative; padding: 76px 0 64px; }
.hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(0, .98fr);
  gap: 30px 58px;
  align-items: center;
}

.pill {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 7px 16px;
  margin-bottom: 22px;
  border-radius: 999px;
  border: 1px solid var(--brand-line);
  background: #fff;
  box-shadow: 0 6px 18px rgba(56, 189, 248, .14);
  font-family: var(--mono);
  font-size: .74rem;
  font-weight: 700;
  letter-spacing: .1em;
  color: var(--brand-d);
}
.pill i {
  width: 7px; height: 7px;
  border-radius: 50%;
  background: var(--em);
  box-shadow: 0 0 0 3px rgba(16, 185, 129, .18);
  flex: 0 0 auto;
}
.hero h1 { margin-bottom: 18px; }
.hero h1 em {
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.hero__lead { font-size: 1.06rem; color: var(--fg-2); max-width: 40em; margin-bottom: 26px; }
.hero__acts { display: flex; flex-wrap: wrap; gap: 12px; margin-bottom: 24px; }
.hero__note {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  list-style: none;
  padding: 0;
  margin: 0;
  font-size: .88rem;
  color: var(--fg-3);
}
.hero__note li { display: flex; align-items: center; gap: 7px; margin: 0; }
.hero__note .ico { width: 15px; height: 15px; color: var(--em); }
.hero__visual { position: relative; min-width: 0; }

/* 首屏数据条：白底 + 每格一条彩色顶边 */
.statbar {
  margin-top: 34px;
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  overflow: hidden;
  box-shadow: var(--sh-sm);
}
.statbar > div {
  position: relative;
  background: #fff;
  padding: 24px;
  transition: background .18s ease;
}
.statbar > div::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  background: var(--cy);
}
.statbar > div:hover { background: var(--bg-4); }
.statbar b {
  display: flex;
  align-items: baseline;
  gap: 4px;
  font-family: var(--mono);
  font-size: 2.05rem;
  font-weight: 800;
  letter-spacing: -.03em;
  line-height: 1.1;
  color: var(--cy);
}
.statbar b em { font-style: normal; font-size: .42em; font-weight: 600; color: var(--fg-4); letter-spacing: 0; }
.statbar span { font-size: .86rem; color: var(--fg-3); }
.statbar > div:nth-child(2)::before { background: var(--vi); }
.statbar > div:nth-child(3)::before { background: var(--em); }
.statbar > div:nth-child(4)::before { background: var(--am); }
.statbar > div:nth-child(5)::before { background: var(--pk); }
.statbar > div:nth-child(2) b { color: var(--vi); }
.statbar > div:nth-child(3) b { color: var(--em); }
.statbar > div:nth-child(4) b { color: var(--am); }
.statbar > div:nth-child(5) b { color: var(--pk); }

/* ---------- 首屏代码窗口：暗色执行台 ----------
   左栏代码 + 右栏执行状态（变量 / dp 表 / 调用栈），或下方数组条；
   顶部进度条，底部滑出运行结果。脚本每次刷新随机换一套「算法 + 配色」，
   配色用 --cw-* 局部变量收在 .codewin 里（见下方的 .codewin--<主题>）。
   脚本不跑（窄屏 / 减少动态效果）时，它就是一张静态代码图。 */
.codewin {
  /* 默认主题（青）也是无脚本时的兜底配色 */
  --cw-bg: #ffffff;
  --cw-bar: #f2f8ff;
  --cw-fg: #3f4d66;
  --cw-line: rgba(148, 163, 184, .3);
  --cw-accent: #0284c7;
  --cw-glow-1: rgba(56, 189, 248, .22);
  --cw-glow-2: rgba(56, 189, 248, .14);
  --cw-kw: #7c3aed;
  --cw-fn: #2563eb;
  --cw-num: #b45309;
  --cw-cm: #9aa8bd;
  --cw-ok: #059669;

  position: relative;
  background: var(--cw-bg);
  border: 1px solid #d8e6f5;
  border-radius: var(--r-lg);
  box-shadow: 0 22px 50px rgba(22, 35, 58, .13), 0 2px 8px rgba(22, 35, 58, .05);
  overflow: hidden;
}
/* 主题：只换强调色与语法色，结构完全一致 */
.codewin--violet { --cw-accent: #7c3aed; --cw-glow-1: rgba(124, 58, 237, .2); --cw-glow-2: rgba(124, 58, 237, .12);
                   --cw-kw: #9333ea; --cw-fn: #6366f1; --cw-num: #b45309; --cw-cm: #9aa8bd; }
.codewin--amber { --cw-accent: #d97706; --cw-glow-1: rgba(217, 119, 6, .2); --cw-glow-2: rgba(217, 119, 6, .12);
                  --cw-kw: #db2777; --cw-fn: #ea580c; --cw-num: #16a34a; --cw-cm: #9aa8bd; }
.codewin--emerald { --cw-accent: #059669; --cw-glow-1: rgba(5, 150, 105, .2); --cw-glow-2: rgba(5, 150, 105, .12);
                   --cw-kw: #0d9488; --cw-fn: #0284c7; --cw-num: #b45309; --cw-cm: #9aa8bd; }
.codewin--rose { --cw-accent: #e11d48; --cw-glow-1: rgba(225, 29, 72, .2); --cw-glow-2: rgba(225, 29, 72, .12);
                   --cw-kw: #c026d3; --cw-fn: #e11d48; --cw-num: #b45309; --cw-cm: #9aa8bd; }

/* 标题栏：红黄绿 + 文件名 + 运行状态灯 */
.codewin__bar {
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 12px 16px;
  background: var(--cw-bar);
  border-bottom: 1px solid var(--cw-line);
}
/* 只作用于标题栏自己的三个圆点：用 > 以免命中状态灯的 <i> */
.codewin__bar > i { width: 11px; height: 11px; border-radius: 50%; background: #d8e6f5; }
.codewin__bar > i:nth-child(1) { background: #ff5f57; }
.codewin__bar > i:nth-child(2) { background: #febc2e; }
.codewin__bar > i:nth-child(3) { background: #28c840; }
.codewin__bar em {
  margin-left: 8px;
  font-family: var(--mono);
  font-size: .76rem;
  font-style: normal;
  color: #7f8ea8;
}

.codewin__stat {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-left: auto;
  font-size: .72rem;
  font-weight: 650;
  color: #8494ad;
  white-space: nowrap;
}
.codewin__stat i {
  width: 7px; height: 7px;
  border-radius: 50%;
  background: #b6c5d8;
  flex: 0 0 auto;
}
.codewin__stat.is-run { color: var(--cw-accent); }
.codewin__stat.is-run i { background: var(--cw-accent); animation: cw-pulse 1.3s ease-in-out infinite; }
.codewin__stat.is-done { color: var(--cw-ok); }
.codewin__stat.is-done i { background: var(--cw-ok); }
@keyframes cw-pulse {
  0%, 100% { box-shadow: 0 0 0 0 var(--cw-glow-1); }
  55% { box-shadow: 0 0 0 5px rgba(0, 0, 0, 0); }
}

/* 执行进度条 */
.codewin__prog { height: 3px; background: #eaf2fb; }
.codewin__prog i {
  display: block;
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--cw-accent), var(--cw-fn));
  box-shadow: 0 0 10px var(--cw-glow-1);
  transition: width .32s linear;
}

/* 主体：左代码、右执行状态 */
.codewin__body { display: grid; grid-template-columns: minmax(0, 1fr) 172px; }
/* 数组类算法：右栏收起，代码占满整宽，数组条放到下方 */
.codewin.is-strip .codewin__body { grid-template-columns: minmax(0, 1fr); }
.codewin.is-strip .codewin__state { display: none; }

.codewin__code {
  position: relative;
  margin: 0;
  padding: 16px 16px 18px;
  font-family: var(--mono);
  font-size: .84rem;
  line-height: 1.85;
  color: var(--cw-fg);
  overflow-x: auto;
  /* 行是块级元素，行与行之间的源码空白必须折叠掉，否则代码里会多出空行 */
  white-space: normal;
}
.codewin__code code { display: block; background: none; padding: 0; font-size: inherit; color: inherit; }
.codewin__code .ln { display: block; white-space: pre; transition: opacity .35s ease; }
/* 行号 */
.codewin__code .no {
  display: inline-block;
  width: 1.9ch;
  margin-right: 13px;
  text-align: right;
  font-style: normal;
  font-size: .92em;
  color: #b3c1d4;
  user-select: none;
}
/* 执行时：还没跑到的行压暗，跑过的行点亮 */
.codewin.is-run .ln { opacity: .4; }
.codewin.is-run .ln.is-lit { opacity: 1; }

/* 语法着色（暗色） */
.c-kw { color: var(--cw-kw, var(--violet)); font-weight: 600; }
.c-fn { color: var(--cw-fn, var(--brand)); }
.c-num { color: var(--cw-num, var(--amber)); }
.c-cm { color: var(--cw-cm, var(--ink-4)); font-style: italic; }
.c-str { color: var(--cw-ok, var(--teal)); }

/* 打字机：每个字符一个 .ch，逐字点亮（.is-typing 由脚本加上，无脚本时全部可见） */
.codewin__code.is-typing .ch { opacity: 0; }
.codewin__code.is-typing .ch.is-in { opacity: 1; }

/* 打字光标 */
.codewin__cursor {
  position: absolute;
  left: 0; top: 0;
  width: 8px;
  height: 1.02em;
  margin-top: .1em;
  border-radius: 1.5px;
  background: var(--cw-accent);
  box-shadow: 0 0 12px var(--cw-accent);
  opacity: 0;
  pointer-events: none;
}
.codewin__cursor.is-on { animation: cw-blink .95s steps(1, end) infinite; }
@keyframes cw-blink {
  0%, 58% { opacity: 1; }
  59%, 100% { opacity: 0; }
}

/* 当前执行行：一条带发光左边界的高亮带，位置由脚本写入 transform */
.codewin__hl {
  position: absolute;
  left: 0; right: 0; top: 0;
  height: 24px;                  /* 兜底值，脚本会按真实行高覆盖 */
  background: linear-gradient(90deg, var(--cw-glow-1), var(--cw-glow-2) 58%, rgba(0, 0, 0, 0));
  box-shadow:
    inset 3px 0 0 var(--cw-accent),
    inset 0 1px 0 var(--cw-glow-2),
    inset 0 -1px 0 var(--cw-glow-2);
  opacity: 0;
  transition: transform .2s cubic-bezier(.33, 1, .68, 1), opacity .22s ease;
  pointer-events: none;
}
.codewin__hl.is-jump { transition: none; }   /* 首次落位不做补间 */

/* 右栏：执行状态 */
.codewin__state {
  padding: 15px 13px;
  border-left: 1px solid var(--cw-line);
  background: #fbfdff;
}
.cw-hd {
  margin: 0 0 9px;
  font-size: .68rem;
  font-weight: 700;
  letter-spacing: .08em;
  color: #64748b;
}
.cw-panel { display: flex; flex-direction: column; gap: 5px; }
.cw-hd--log { margin-top: 15px; }

/* 变量行（数论 / 递推类） */
.cw-row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 8px;
  margin: 0;
  padding: 5px 10px 6px;
  border-radius: 9px;
  background: #f4f9ff;
}
.cw-k { font-family: var(--mono); font-size: .72rem; color: #7f8ea8; }
.cw-v {
  font-family: var(--mono);
  font-size: 1.3rem;
  font-weight: 700;
  line-height: 1.1;
  color: #16233a;
}
/* 值变化时弹一下，让「哪一步改了哪个变量」看得见 */
.cw-v.is-hit {
  color: var(--cw-accent);
  animation: cw-pop .45s cubic-bezier(.33, 1, .68, 1) both;
}
@keyframes cw-pop {
  0% { transform: scale(.72); opacity: .25; }
  55% { transform: scale(1.09); }
  100% { transform: scale(1); opacity: 1; }
}

/* 递推表（动态规划）：一行一行填出来 */
.cw-li {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 6px;
  margin: 0;
  padding: 4px 9px 5px;
  border-radius: 7px;
  background: #f4f9ff;
  font-family: var(--mono);
  font-size: .72rem;
  color: #6f84a6;
  animation: cw-slide .28s ease both;
}
.cw-li b { color: #16233a; font-weight: 700; }
.cw-li.is-new { background: var(--cw-glow-2); color: #334155; }
.cw-li.is-new b { color: var(--cw-accent); text-shadow: 0 0 12px var(--cw-accent); }

/* 调用栈（递归）：一层层压上去，再一层层弹回来 */
.cw-fr {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 6px;
  margin: 0;
  padding: 5px 9px;
  border-radius: 7px;
  border-left: 2px solid var(--cw-accent);
  background: #f4f9ff;
  font-family: var(--mono);
  font-size: .72rem;
  color: #3f4d66;
  animation: cw-slide .26s ease both;
}
.cw-fr b { color: var(--cw-accent); font-weight: 700; }
.cw-fr.is-out { opacity: 0; transform: translateY(8px); transition: opacity .32s ease, transform .32s ease; }

/* 执行日志 */
.cw-log { display: flex; flex-direction: column; gap: 4px; margin-top: 4px; }
.cw-log p {
  display: flex;
  align-items: baseline;
  /* 值与标签相邻而不是顶到右边缘：右下角的悬浮卡会盖住面板右侧 */
  justify-content: flex-start;
  gap: 8px;
  margin: 0;
  font-family: var(--mono);
  font-size: .68rem;
  color: #64748b;
  animation: cw-slide .28s ease both;
}
.cw-log p b { font-weight: 700; }
.cw-log p.is-new { color: #334155; }
.cw-log p.is-new b { color: var(--cw-accent); }
@keyframes cw-slide {
  from { opacity: 0; transform: translateY(-4px); }
  to { opacity: 1; transform: none; }
}

/* 数组条（查找 / 排序类）：代码下方横跨整宽 */
.cw-strip {
  padding: 22px 16px 15px;
  border-top: 1px solid var(--cw-line);
  background: #fbfdff;
}
.cw-strip[hidden] { display: none; }
.cw-arr-hd {
  margin: 0 0 10px;
  font-family: var(--mono);
  font-size: .68rem;
  letter-spacing: .06em;
  color: #7f8ea8;
}
.cw-cells { display: flex; gap: 7px; }
.cw-cell {
  position: relative;
  flex: 1 1 0;
  min-width: 0;
  padding: 10px 4px 9px;
  border-radius: 9px;
  border: 1px solid transparent;
  background: #eef5ff;
  color: #3f4d66;
  font-family: var(--mono);
  font-size: .95rem;
  font-weight: 700;
  text-align: center;
  transition: background .25s ease, border-color .25s ease, color .25s ease,
              transform .25s ease, opacity .25s ease;
}
.cw-cell.is-dim { opacity: .35; }                                  /* 二分：落在区间外 */
.cw-cell.is-cmp {                                                 /* 冒泡：正在比较 */
  background: rgba(245, 158, 11, .2);
  border-color: rgba(245, 158, 11, .55);
  color: #fcd34d;
  transform: translateY(-3px);
}
.cw-cell.is-mid, .cw-cell.is-swap {                               /* 命中的 mid / 正在交换 */
  background: #fff;
  border-color: var(--cw-accent);
  color: var(--cw-accent);
  transform: translateY(-3px);
}
.cw-cell.is-hit { background: #e9fbf4; border-color: #6ee7b7; color: #047857; }
.cw-cell.is-done { background: #f0fdf7; color: #059669; }   /* 已排好 */
.cw-cell-p {
  position: absolute;
  left: -6px; right: -6px;
  top: -16px;
  font-family: var(--mono);
  font-size: .6rem;
  font-weight: 700;
  font-style: normal;
  letter-spacing: .04em;
  color: var(--cw-accent);
  text-align: center;
  white-space: nowrap;
}

/* 运行结果：贴住窗口底边，不占高度、不推挤首屏排版 */
.codewin__out {
  position: absolute;
  left: 0; right: 0; bottom: 0;
  display: flex;
  align-items: center;
  gap: 9px;
  padding: 13px 18px;
  background: #e9fbf4;
  border-top: 1px solid #b6ecd8;
  font-family: var(--mono);
  font-size: .88rem;
  color: #047857;
  transform: translateY(101%);
  opacity: 0;
  transition: transform .36s cubic-bezier(.33, 1, .68, 1), opacity .3s ease;
  pointer-events: none;
}
.codewin__out.is-on { transform: none; opacity: 1; }
.codewin__out-c { color: var(--cw-ok); font-weight: 700; }
.codewin__out-v {
  font-weight: 700;
  color: #047857;
}

/* 窄屏：不跑动画，右栏收起，代码占满整宽 */
@media (max-width: 860px) {
  .codewin__body { grid-template-columns: minmax(0, 1fr); }
  .codewin__state { display: none; }
}

/* 首屏数据条 */


/* ---------- 快速入口：首屏直达入口带 ---------- */
.quick-wrap { position: relative; grid-column: 1 / -1; }
.quick {
  position: relative;
  overflow: hidden;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 20px;
  padding: 14px 18px;
  background: #fff;
  border: 1px solid var(--brand-line);
  border-radius: var(--r-lg);
  box-shadow: var(--sh-sm);
}
.quick::after {
  content: "";
  position: absolute;
  top: -60%;
  bottom: -60%;
  left: -180px;
  width: 140px;
  background: linear-gradient(100deg, rgba(255, 255, 255, 0), rgba(56, 189, 248, .3), rgba(255, 255, 255, 0));
  transform: skewX(-18deg);
  animation: quick-sheen 7s cubic-bezier(.5, 0, .5, 1) infinite;
  pointer-events: none;
}
@keyframes quick-sheen {
  0% { left: -180px; }
  60%, 100% { left: 108%; }
}
@media (prefers-reduced-motion: reduce) {
  .quick::after { display: none; }
}

.quick__title {
  display: flex;
  align-items: center;
  gap: 9px;
  flex: 0 0 auto;
  margin: 0;
  padding-right: 20px;
  border-right: 1px solid var(--line);
  font-family: var(--mono);
  font-size: .8rem;
  font-weight: 700;
  letter-spacing: .14em;
  color: var(--brand-d);
  text-transform: uppercase;
  white-space: nowrap;
}
.quick__title .ico { width: 17px; height: 17px; }
.quick__title::before {
  content: "";
  width: 4px;
  height: 20px;
  border-radius: 3px;
  background: var(--grad);
}

.tiles {
  display: flex;
  flex: 1 1 auto;
  flex-wrap: wrap;
  gap: 10px;
  min-width: 0;
}
.tile {
  --tone: #0284c7;
  --tone-line: #bae6fd;
  --tone-soft: #e6f6ff;
  flex: 1 1 auto;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 9px 15px 9px 9px;
  background: var(--tone-soft);
  border: 1px solid var(--tone-line);
  border-radius: 999px;
  font-size: .93rem;
  font-weight: 700;
  line-height: 1.3;
  color: var(--tone);
  white-space: nowrap;
  transition: background .16s ease, border-color .16s ease, box-shadow .16s ease, transform .16s ease;
}
.tile--amber { --tone: #b45309; --tone-line: #fde3b0; --tone-soft: #fff7e6; }
.tile--brand { --tone: #1d4ed8; --tone-line: #c7dafd; --tone-soft: #edf3ff; }
.tile--teal { --tone: #047857; --tone-line: #b3ecd8; --tone-soft: #e7fbf3; }
.tile--violet { --tone: #6d28d9; --tone-line: #ddd0fb; --tone-soft: #f4f0ff; }
.tile--green { --tone: #047857; --tone-line: #b3ecd8; --tone-soft: #e7fbf3; }
.tile--rose { --tone: #be123c; --tone-line: #fbd0da; --tone-soft: #fff1f4; }

.tile::after {
  content: "→";
  font-weight: 700;
  color: var(--tone);
  opacity: .5;
  transition: opacity .18s ease, transform .18s ease;
}
.tile:hover {
  background: #fff;
  border-color: var(--tone);
  color: var(--tone);
  box-shadow: 0 10px 24px rgba(22, 35, 58, .1);
  transform: translateY(-2px);
  text-decoration: none;
}
.tile:hover::after { opacity: 1; transform: translateX(2px); }
.tile .tile__ic {
  width: 32px; height: 32px;
  border-radius: 50%;
  background: #fff;
  display: grid;
  place-items: center;
  flex: 0 0 auto;
  transition: transform .18s ease;
}
.tile:hover .tile__ic { transform: scale(1.08) rotate(-4deg); }
.tile .tile__ic .ico { width: 17px; height: 17px; }
.tile__t { display: block; }

.hero__grid + .statbar { margin-top: 30px; }

/* ---------- 卡片 ---------- */
.card {
  position: relative;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  padding: 28px;
  box-shadow: var(--sh-sm);
  transition: border-color .18s ease, box-shadow .18s ease, transform .18s ease;
}
/* 悬停只做描边 + 投影 + 轻微上浮，不加顶部横线 */
.card:hover {
  border-color: var(--brand-line);
  box-shadow: var(--sh-cy);
  transform: translateY(-4px);
}
.card h3 { margin-bottom: .5em; }
.card p { color: var(--fg-2); font-size: .96rem; }
.card__ic {
  width: 48px; height: 48px;
  border-radius: 15px;
  display: grid;
  place-items: center;
  margin-bottom: 18px;
}
.card__ic .ico { width: 23px; height: 23px; }

/* ---------- 正文排版 ---------- */
.prose { max-width: none; }
.prose > p, .sec-head > p, .qa__body > p, .sw__body > p, .course__for, .cbox__n {
  text-align: justify;
  text-justify: inter-ideograph;
  overflow-wrap: break-word;
}
.prose > p { color: var(--fg-2); }
.prose h3 { margin: 1.9em 0 .7em; }
.prose h3:first-child { margin-top: 0; }
.prose > p + ul, .prose > p + ol { margin-top: -.2em; }

/* 对勾清单 */
.ticks { list-style: none; padding: 0; }
.ticks li {
  position: relative;
  padding-left: 30px;
  margin: .55em 0;
  color: var(--fg-2);
}
.ticks li::before {
  content: "";
  position: absolute;
  left: 0; top: .42em;
  width: 18px; height: 18px;
  border-radius: 50%;
  background-color: var(--em-soft);
  background-image: url("data:image/svg+xml;charset=utf-8,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%2310b981' stroke-width='3.4' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='m5 12.5 4.5 4.5L19 7'/%3E%3C/svg%3E");
  background-size: 11px;
  background-position: center;
  background-repeat: no-repeat;
}
.ticks li strong { color: var(--fg); }
.ticks--brand li::before {
  background-color: var(--cy-soft);
  background-image: url("data:image/svg+xml;charset=utf-8,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%230ea5e9' stroke-width='3.4' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='m5 12.5 4.5 4.5L19 7'/%3E%3C/svg%3E");
}

/* 定义列表 */
.deflist { margin: 0; }
.deflist dt {
  font-family: var(--mono);
  font-size: .72rem;
  letter-spacing: .1em;
  color: var(--fg-4);
  text-transform: uppercase;
  margin-top: 16px;
}
.deflist dt:first-child { margin-top: 0; }
.deflist dd { margin: 3px 0 0; color: var(--fg); font-size: .96rem; }

/* 侧栏面板 */
.panel {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  padding: 24px;
  box-shadow: var(--sh-sm);
}
.aside { position: sticky; top: 104px; }
.aside--static { position: static; }
.aside__title, .panel__title {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 16px;
  padding-bottom: 13px;
  border-bottom: 1px solid var(--line-2);
  font-family: var(--mono);
  font-size: .74rem;
  font-weight: 700;
  letter-spacing: .14em;
  color: var(--brand-d);
  text-transform: uppercase;
}
.panel__title .ico { width: 15px; height: 15px; }

/* 速览事实：面板里两列排布的「标签 + 值」 */
.facts { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px 24px; }
.facts span {
  display: block;
  margin-bottom: 3px;
  font-family: var(--mono);
  font-size: .7rem;
  letter-spacing: .1em;
  color: var(--fg-4);
  text-transform: uppercase;
}
.facts b { font-size: .96rem; font-weight: 700; color: var(--fg); }
@media (max-width: 560px) {
  .facts { grid-template-columns: 1fr; }
}

/* 「怎么学 / 怎么练 / 怎么验」三栏 */
.howcol p { color: var(--fg-2); font-size: .95rem; }
.how { display: flex; align-items: center; gap: 11px; margin-bottom: .6em; }
.how__ic {
  width: 36px; height: 36px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  flex: 0 0 auto;
}
.how__ic .ico { width: 18px; height: 18px; }

/* 横排面板：文字在左、操作在右 */
.panel--row {
  display: flex;
  flex-wrap: wrap;
  gap: 18px 28px;
  align-items: center;
  justify-content: space-between;
}
.panel--row > div { flex: 1 1 420px; min-width: 0; }

/* ---------- 表格 ---------- */
.tbl-wrap {
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  overflow: hidden;
  background: #fff;
  box-shadow: var(--sh-sm);
}
.tbl-scroll { overflow-x: auto; }
.tbl { width: 100%; border-collapse: collapse; font-size: .95rem; }
.tbl thead th {
  background: var(--bg-2);
  padding: 14px 20px;
  text-align: left;
  font-family: var(--mono);
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .1em;
  color: var(--fg-3);
  text-transform: uppercase;
  white-space: nowrap;
}
.tbl tbody th, .tbl tbody td {
  padding: 15px 20px;
  border-top: 1px solid var(--line-2);
  text-align: left;
  vertical-align: top;
  color: var(--fg-2);
}
.tbl tbody th { color: var(--fg); font-weight: 700; }
.tbl .num {
  font-family: var(--mono);
  font-weight: 700;
  color: var(--brand-d);
  white-space: nowrap;
}
.tbl tbody tr:hover { background: var(--bg-4); }

/* ---------- 教练卡 ---------- */
.teacher {
  display: grid;
  grid-template-columns: 340px minmax(0, 1fr);
  gap: 32px;
  align-items: start;
}
.tcard {
  position: relative;
  background: linear-gradient(165deg, #f0f9ff, #ffffff 55%, #f6f2ff);
  border: 1px solid var(--brand-line);
  border-radius: var(--r-xl);
  padding: 32px 28px;
  box-shadow: var(--sh);
  overflow: hidden;
}
/* 卡片顶部不再放渐变横条 */
.tcard__ava {
  width: 88px; height: 88px;
  border-radius: 26px;
  background: var(--grad);
  color: #fff;
  display: grid;
  place-items: center;
  font-size: 1.9rem;
  font-weight: 850;
  letter-spacing: -.02em;
  box-shadow: 0 14px 30px rgba(56, 189, 248, .38);
  margin-bottom: 20px;
}
.tcard__role {
  font-family: var(--mono);
  font-size: .74rem;
  letter-spacing: .12em;
  color: var(--brand-d);
  text-transform: uppercase;
  margin-bottom: 8px;
}
.tcard__bio { color: var(--fg-2); font-size: .95rem; }
.tcard__tags { display: flex; flex-wrap: wrap; gap: 8px; margin: 18px 0 0; padding: 0; list-style: none; }
.tcard__tags li {
  font-family: var(--mono);
  font-size: .7rem;
  letter-spacing: .04em;
  padding: 5px 12px;
  border-radius: 999px;
  background: #fff;
  border: 1px solid var(--line);
  color: var(--fg-2);
}

/* 通栏教练卡：头像在左、介绍居中、按钮在右 */
.tcard--wide {
  display: flex;
  align-items: center;
  gap: 30px;
  padding: 28px 34px;
}
.tcard--wide .tcard__ava { margin: 0; width: 74px; height: 74px; font-size: 1.6rem; border-radius: 22px; }
.tcard__main { flex: 1 1 auto; min-width: 0; }
.tcard--wide h3 { margin-bottom: .18em; }
.tcard--wide .tcard__bio { max-width: 78ch; }
.tcard--wide .tcard__tags { margin-top: 12px; }
.tcard--wide > .btn { flex: 0 0 auto; }
@media (max-width: 860px) {
  .tcard--wide { flex-direction: column; align-items: flex-start; gap: 20px; padding: 24px; }
  .tcard--wide .tcard__ava { width: 60px; height: 60px; font-size: 1.3rem; border-radius: 18px; }
  .tcard--wide > .btn { width: 100%; }
}

/* 资质徽章墙：四张带色的小卡，一眼看到「什么资质」 */
.badges { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 18px; }
.badge {
  position: relative;
  padding: 22px 22px 20px;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background: #fff;
  box-shadow: var(--sh-sm);
  transition: border-color .18s ease, box-shadow .18s ease, transform .18s ease;
}
.badge:hover { border-color: var(--brand-line); box-shadow: var(--sh-cy); transform: translateY(-3px); }
.badge__ic {
  width: 42px; height: 42px;
  border-radius: 13px;
  display: grid;
  place-items: center;
  margin-bottom: 14px;
}
.badge__ic .ico { width: 21px; height: 21px; }
.badge b { display: block; font-size: 1.02rem; margin-bottom: 3px; }
.badge span:not(.badge__ic) { font-size: .86rem; color: var(--fg-3); }
.badge--bl { background: linear-gradient(165deg, #f2f7ff, #fff 62%); }
.badge--vi { background: linear-gradient(165deg, #f7f2ff, #fff 62%); }
.badge--em { background: linear-gradient(165deg, #eefbf6, #fff 62%); }
.badge--am { background: linear-gradient(165deg, #fff8ea, #fff 62%); }
@media (max-width: 1080px) { .badges { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 560px) { .badges { grid-template-columns: 1fr; } }

/* ---------- 课程卡 ---------- */
.course {
  position: relative;
  display: flex;
  flex-direction: column;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  padding: 26px;
  box-shadow: var(--sh-sm);
  transition: border-color .18s ease, box-shadow .18s ease, transform .18s ease;
}
.course:hover {
  border-color: var(--brand-line);
  box-shadow: var(--sh-cy);
  transform: translateY(-4px);
}
.course__top { display: flex; align-items: center; gap: 14px; margin-bottom: 16px; }
.course__ic {
  width: 46px; height: 46px;
  border-radius: 14px;
  display: grid;
  place-items: center;
  flex: 0 0 auto;
}
.course__ic .ico { width: 22px; height: 22px; }
.course__lvl {
  font-family: var(--mono);
  font-size: .7rem;
  font-weight: 700;
  letter-spacing: .1em;
  padding: 5px 12px;
  border-radius: 999px;
  background: var(--cy-soft);
  border: 1px solid var(--brand-line);
  color: var(--brand-d);
  white-space: nowrap;
}
.course h3 { margin-bottom: .35em; }
.course__for { color: var(--fg-3); font-size: .88rem; margin-bottom: 14px; }
.course__list { list-style: none; padding: 0; margin: 0 0 18px; }
.course__list li {
  position: relative;
  list-style: none;
  padding-left: 22px;
  margin: .45em 0;
  color: var(--fg-2);
  font-size: .93rem;
}
.course__list li::before {
  content: "";
  position: absolute;
  left: 4px; top: .62em;
  width: 7px; height: 7px;
  border-radius: 3px;
  background: var(--brand);
  box-shadow: 0 0 8px rgba(14, 165, 233, .5);
}
.course__foot {
  margin-top: auto;
  padding-top: 16px;
  border-top: 1px solid var(--line-2);
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
  justify-content: space-between;
  font-size: .86rem;
  color: var(--fg-3);
}
.course__act { margin-top: 16px; display: flex; flex-wrap: wrap; gap: 10px; }
.course--wide { grid-column: span 2; }
.course--feature {
  grid-column: 1 / -1;
  background: linear-gradient(120deg, #eef8ff, #ffffff 45%, #f6f0ff);
  border-color: var(--brand-line);
}
.grid--courses { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 20px; }

/* 通栏重点课程：左要点、右信息栏，两侧都填满 */
.course--split {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr);
  gap: 26px 52px;
  align-items: start;
}
.course__side { display: flex; flex-direction: column; gap: 22px; min-width: 0; }
.course__side .facts { grid-template-columns: minmax(0, 1fr); gap: 13px; }
.course__side .facts b { font-size: .93rem; }
.course__side .course__act { margin-top: 0; }
@media (max-width: 1080px) {
  .course--split { grid-template-columns: minmax(0, 1fr); }
}

/* ---------- 知识体系 ---------- */
.treegroup {
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background: #fff;
  overflow: hidden;
  box-shadow: var(--sh-sm);
}
.treegroup + .treegroup { margin-top: 22px; }
.treegroup__head {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 18px 22px;
  border-bottom: 1px solid var(--line-2);
  background: var(--bg-2);
}
.treegroup__head h3 { margin: 0; font-size: 1.05rem; }
.treegroup__head span { margin-left: auto; font-family: var(--mono); font-size: .76rem; color: var(--fg-3); }
.treegroup__head .btn { margin-left: auto; }
.treegroup__head .card__ic { width: 36px; height: 36px; margin: 0; border-radius: 11px; }
.treegroup__head .card__ic .ico { width: 18px; height: 18px; }

/* ---------- 问卷式列表块（联系方式里的信息格） ---------- */
.cbox {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--r);
  padding: 18px 20px;
  box-shadow: var(--sh-sm);
}
.cbox__k {
  display: flex;
  align-items: center;
  gap: 7px;
  margin: 0 0 8px;
  font-family: var(--mono);
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .1em;
  color: var(--brand-d);
  text-transform: uppercase;
}
.cbox__k .ico { width: 15px; height: 15px; }
.cbox__v {
  margin: 0;
  font-size: 1.16rem;
  font-weight: 750;
  color: var(--fg);
  letter-spacing: -.01em;
  word-break: break-all;
}
.cbox__v a { color: var(--fg); }
.cbox__v a:hover { color: var(--brand-d); }
.cbox__n { margin: 6px 0 0; font-size: .82rem; color: var(--fg-3); }

/* ---------- 问答 ---------- */
.qa { display: flex; flex-direction: column; gap: 12px; }
/* 问答正文排两列，长页面不用一路下拉 */
.qa--grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  align-items: start;
}
@media (max-width: 1080px) { .qa--grid { grid-template-columns: 1fr; } }
.qa__item {
  border: 1px solid var(--line);
  border-radius: var(--r);
  background: #fff;
  overflow: hidden;
  box-shadow: var(--sh-sm);
  transition: border-color .18s ease, box-shadow .18s ease;
}
.qa__item:hover { border-color: var(--brand-line); }
.qa__item.is-open,
.qa__item[open] { border-color: var(--brand-line); box-shadow: var(--sh-cy); }
.qa__q {
  display: flex;
  align-items: baseline;
  gap: 14px;
  width: 100%;
  margin: 0;
  padding: 18px 22px;
  border: 0;
  background: none;
  color: var(--fg);
  font-family: inherit;
  font-size: 1rem;
  font-weight: 700;
  text-align: left;
  cursor: pointer;
}
.qa__q:hover { color: var(--brand-d); }
.qa__num {
  font-family: var(--mono);
  font-size: .78rem;
  font-weight: 700;
  color: var(--brand-d);
  flex: 0 0 auto;
}
.qa__meta { padding: 0 22px 18px; }
.qa__meta .ticks { margin: 0; }
.qa__body { padding: 0 22px 22px; }
.qa__body > p { color: var(--fg-2); font-size: .96rem; }
.qa__answer {
  margin-top: 14px;
  padding: 16px 18px;
  border-radius: var(--r-sm);
  background: var(--bg-2);
  border-left: 3px solid var(--brand);
  color: var(--fg-2);
  font-size: .95rem;
}
.faqwrap { padding: 24px 0 0; }
.qa-cat:first-of-type { padding-top: 8px; }
.qa-cat__head {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 0 0 18px;
  padding-bottom: 13px;
  border-bottom: 1px solid var(--line);
  font-family: var(--mono);
  font-size: .8rem;
  font-weight: 700;
  letter-spacing: .12em;
  color: #7c3aed;
  text-transform: uppercase;
}
.qa-cat__head .ico { width: 16px; height: 16px; }

/* ---------- 下载清单 ---------- */
/* 下载清单：一条软件一条宽行 —— 名字与「前往下载」都要一眼看到 */
.sw { display: grid; gap: 18px; }
.sw__row {
  display: grid;
  grid-template-columns: minmax(0, 296px) minmax(0, 1fr) 186px;
  gap: 24px 40px;
  align-items: center;
  padding: 30px 34px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  box-shadow: var(--sh-sm);
  transition: border-color .18s ease, box-shadow .18s ease;
}
.sw__row:hover {
  border-color: var(--brand-line);
  box-shadow: var(--sh-cy);
}
.sw__name { display: flex; gap: 18px; align-items: flex-start; }
.sw__name h3 { margin: 0 0 .3em; font-size: 1.22rem; }
/* 图标更大、底色更实，像「应用图标」而不是小标记 */
.sw__ic { width: 60px; height: 60px; border-radius: 18px; }
.sw__ic .ico { width: 29px; height: 29px; }
/* 要点在宽行里排两列，不浪费行宽 */
.sw__notes { columns: 2; column-gap: 32px; }
.sw__notes li { break-inside: avoid; }
/* 下载按钮是这一页的主动作：占满右栏、更大、带投影 */
.sw__act { text-align: right; }
.sw__act .btn { width: 100%; padding: 15px 20px; font-size: 1rem; border-radius: 13px; }
@media (max-width: 1080px) {
  .sw__row { grid-template-columns: minmax(0, 1fr); gap: 18px; padding: 26px 24px; }
  .sw__act { text-align: left; }
  .sw__act .btn { width: auto; padding: 13px 24px; }
  .sw__notes { columns: 1; }
}
.sw__ic {
  width: 50px; height: 50px;
  border-radius: 15px;
  display: grid;
  place-items: center;
  flex: 0 0 auto;
}
.sw__ic .ico { width: 24px; height: 24px; }
.sw__tag {
  display: inline-block;
  margin-left: 7px;
  vertical-align: 2px;
  padding: 2px 10px;
  border-radius: 999px;
  background: var(--am-soft);
  border: 1px solid #fde3b0;
  color: #b45309;
  font-family: var(--mono);
  font-size: .68rem;
  font-weight: 700;
}
.sw__meta { font-family: var(--mono); font-size: .78rem; color: var(--fg-3); margin: 0; }
.sw__body { color: var(--fg-2); font-size: .95rem; }
.sw__body > p { margin-bottom: .8em; }
.sw__notes { list-style: none; padding: 0; margin: 0; font-size: .9rem; }
.sw__notes li {
  position: relative;
  padding-left: 19px;
  margin-bottom: .32em;
  color: var(--fg-3);
}
.sw__notes li::before {
  content: "";
  position: absolute;
  left: 2px; top: .66em;
  width: 7px; height: 7px;
  border-radius: 3px;
  background: var(--brand);
}
.sw__act { text-align: right; }

/* 安装清单：一行一步 —— 序号 / 装什么 / 要不要装 / 为什么 / 跳到该软件 */
.orderlist {
  list-style: none;
  padding: 0;
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background: #fff;
  box-shadow: var(--sh-sm);
  overflow: hidden;
}
.orderlist__row {
  display: grid;
  grid-template-columns: 52px minmax(0, 1fr) 132px;
  gap: 22px;
  align-items: center;
  padding: 24px 30px;
  transition: background .16s ease;
}
.orderlist__row + .orderlist__row { border-top: 1px solid var(--line-2); }
.orderlist__row:hover { background: var(--bg-2); }
.orderlist__n {
  display: grid;
  place-items: center;
  width: 46px; height: 46px;
  border-radius: 14px;
  background: var(--grad);
  color: #fff;
  font-family: var(--mono);
  font-size: .86rem;
  font-weight: 700;
  box-shadow: 0 8px 18px rgba(56, 189, 248, .28);
}
.orderlist__row:nth-child(2) .orderlist__n { background: linear-gradient(120deg, #a855f7, #6366f1); box-shadow: 0 8px 18px rgba(139, 92, 246, .28); }
.orderlist__row:nth-child(3) .orderlist__n { background: linear-gradient(120deg, #10b981, #0ea5e9); box-shadow: 0 8px 18px rgba(16, 185, 129, .28); }
.orderlist__row:nth-child(4) .orderlist__n { background: linear-gradient(120deg, #fbbf24, #fb7185); box-shadow: 0 8px 18px rgba(251, 113, 133, .28); }
.orderlist__head { display: flex; flex-wrap: wrap; align-items: center; gap: 10px; margin-bottom: 5px; }
.orderlist__head h3 { margin: 0; font-size: 1.08rem; }
.orderlist__badge {
  font-family: var(--mono);
  font-size: .68rem;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: 999px;
  white-space: nowrap;
}
.orderlist__badge--must { background: var(--ro-soft); color: #be123c; }
.orderlist__badge--pick { background: var(--cy-soft); color: #0284c7; }
.orderlist__badge--opt { background: #f1f5fb; color: var(--fg-3); }
.orderlist__main p { margin: 0; color: var(--fg-2); font-size: .94rem; }
.orderlist__link { text-align: right; font-size: .9rem; font-weight: 650; white-space: nowrap; }
@media (max-width: 860px) {
  .orderlist__row { grid-template-columns: 46px minmax(0, 1fr); gap: 16px; padding: 20px 22px; }
  .orderlist__n { width: 40px; height: 40px; border-radius: 12px; font-size: .78rem; }
  .orderlist__link { grid-column: 2; text-align: left; }
}

/* 选型速查：三列的事实格 */
.selgrid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px 28px; }
.selgrid dt {
  font-family: var(--mono);
  font-size: .72rem;
  letter-spacing: .1em;
  color: var(--brand-d);
  text-transform: uppercase;
}
.selgrid dd { margin: 4px 0 0; color: var(--fg); font-size: .95rem; }
@media (max-width: 1080px) { .selgrid { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 620px)  { .selgrid { grid-template-columns: 1fr; } }

/* 下载页顶部：软件快速跳转条（粘在顶栏下面） */
.dljump {
  position: sticky;
  top: 84px;
  z-index: 20;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 24px;
  padding: 12px 0;
  background: linear-gradient(180deg, var(--bg) 72%, rgba(255, 255, 255, 0));
}
.dljump a {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 8px 15px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: #fff;
  color: var(--fg-2);
  font-size: .88rem;
  font-weight: 650;
  box-shadow: var(--sh-sm);
}
.dljump a:hover { border-color: var(--brand-line); color: var(--brand-d); background: var(--cy-soft); }
.dljump a b { font-family: var(--mono); font-size: .72rem; color: var(--fg-4); font-weight: 700; }

/* ---------- 步骤 ---------- */
.steps { list-style: none; padding: 0; margin: 0; counter-reset: step; }
.steps li {
  position: relative;
  padding-left: 62px;
  padding-bottom: 26px;
  margin: 0 0 0 19px;
  border-left: 2px dashed var(--brand-line);
}
.steps li:last-child { border-left-color: transparent; padding-bottom: 0; }
.steps li::before {
  counter-increment: step;
  content: counter(step, decimal-leading-zero);
  position: absolute;
  left: -19px; top: -2px;
  width: 38px; height: 38px;
  border-radius: 13px;
  display: grid;
  place-items: center;
  background: var(--grad);
  color: #fff;
  font-family: var(--mono);
  font-size: .78rem;
  font-weight: 700;
  box-shadow: 0 8px 18px rgba(56, 189, 248, .32);
}
.steps li h3 { margin-bottom: .3em; }
.steps li p { color: var(--fg-2); font-size: .94rem; }

/* 训练流程：四步横向 + 闭环提示 */
.flow4 { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 22px; }
.flow4__step {
  position: relative;
  padding: 26px 24px 24px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  box-shadow: var(--sh-sm);
  transition: border-color .18s ease, box-shadow .18s ease, transform .18s ease;
}
.flow4__step:hover { border-color: var(--brand-line); box-shadow: var(--sh-cy); transform: translateY(-3px); }
/* 步骤之间的连接线 */
.flow4__step + .flow4__step::before {
  content: "";
  position: absolute;
  left: -22px; top: 46px;
  width: 22px; height: 2px;
  background: var(--brand-line);
}
.flow4__n {
  display: inline-grid;
  place-items: center;
  width: 40px; height: 40px;
  margin-bottom: 14px;
  border-radius: 13px;
  background: var(--grad);
  color: #fff;
  font-family: var(--mono);
  font-size: .82rem;
  font-weight: 700;
  box-shadow: 0 8px 18px rgba(56, 189, 248, .3);
}
.flow4__step:nth-child(2) .flow4__n { background: linear-gradient(120deg, #a855f7, #6366f1); box-shadow: 0 8px 18px rgba(139, 92, 246, .3); }
.flow4__step:nth-child(3) .flow4__n { background: linear-gradient(120deg, #10b981, #0ea5e9); box-shadow: 0 8px 18px rgba(16, 185, 129, .3); }
.flow4__step:nth-child(4) .flow4__n { background: linear-gradient(120deg, #fbbf24, #fb7185); box-shadow: 0 8px 18px rgba(251, 113, 133, .3); }
.flow4__step h3 { margin-bottom: .4em; font-size: 1.05rem; }
.flow4__step p { margin: 0; color: var(--fg-2); font-size: .93rem; }
.flow4__loop {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  margin: 20px 0 0;
  padding: 18px 24px;
  border: 1px dashed var(--brand-line);
  border-radius: var(--r);
  background: var(--cy-soft);
  color: #0c4a6e;
  font-size: .94rem;
}
.flow4__loop .ico { width: 20px; height: 20px; color: var(--brand-d); margin-top: 2px; }
@media (max-width: 1080px) {
  .flow4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .flow4__step + .flow4__step::before { display: none; }
}
@media (max-width: 640px) {
  .flow4 { grid-template-columns: 1fr; }
}

/* ---------- 团队 ---------- */
.teamgrid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 22px; }
.teamcol {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  padding: 26px;
  box-shadow: var(--sh-sm);
  transition: border-color .18s ease, box-shadow .18s ease, transform .18s ease;
}
.teamcol:hover { border-color: var(--brand-line); box-shadow: var(--sh-cy); transform: translateY(-3px); }
.teamcol h3 { margin-bottom: .5em; display: flex; align-items: center; gap: 9px; }
.teamcol h3 .ico { color: var(--brand); }
.teamcol p { color: var(--fg-2); font-size: .94rem; }
.teamcol ul { padding-left: 1.15em; }
.teamcol li { color: var(--fg-2); font-size: .93rem; }

/* ---------- 行动区 ---------- */
.cta {
  position: relative;
  overflow: hidden;
  padding: 48px;
  border-radius: var(--r-xl);
  background: linear-gradient(120deg, #eaf7ff, #ffffff 48%, #f5efff);
  border: 1px solid var(--brand-line);
  box-shadow: var(--sh);
  text-align: center;
}
.cta h2 { margin-bottom: .4em; }
.cta p { color: var(--fg-2); max-width: 60ch; margin-inline: auto; }
.cta__act { display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; margin-top: 26px; }

/* 结尾两条路：自己先看 / 直接找校队 */
.fork { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 22px; }
.fork__col {
  padding: 38px 36px;
  border: 1px solid var(--brand-line);
  border-radius: var(--r-xl);
  background: linear-gradient(150deg, #eef8ff, #fff 58%);
  box-shadow: var(--sh-sm);
}
.fork__col--alt {
  border-color: #ddd0fb;
  background: linear-gradient(150deg, #f7f1ff, #fff 58%);
}
.fork__tag {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 12px;
  font-family: var(--mono);
  font-size: .74rem;
  font-weight: 700;
  letter-spacing: .14em;
  color: var(--brand-d);
  text-transform: uppercase;
}
.fork__col--alt .fork__tag { color: #6d28d9; }
.fork__tag .ico { width: 15px; height: 15px; }
.fork__col h2 { font-size: clamp(1.3rem, 2vw, 1.62rem); margin-bottom: .45em; }
.fork__col > p { color: var(--fg-2); font-size: .96rem; margin-bottom: 0; }
.fork__col .ticks { margin: 18px 0 24px; }
.fork__col .ticks li { font-size: .93rem; }
@media (max-width: 860px) {
  .fork { grid-template-columns: 1fr; }
  .fork__col { padding: 28px 24px; }
}

/* ---------- 联系区 ---------- */
.contact {
  position: relative;
  overflow: hidden;
  padding: 46px;
  border-radius: var(--r-xl);
  background: linear-gradient(125deg, #eef8ff, #ffffff 50%, #f6f1ff);
  border: 1px solid var(--brand-line);
  box-shadow: var(--sh);
}
.contact__grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 16px; align-items: stretch; margin-top: 24px; }
.contact__acts { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 26px; }

.contact-fab {
  position: fixed;
  right: 26px;
  bottom: 26px;
  z-index: 90;
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 14px 22px;
  border-radius: 999px;
  background: var(--grad);
  color: #fff;
  font-weight: 800;
  font-size: .93rem;
  box-shadow: 0 14px 34px rgba(56, 189, 248, .4);
}
.contact-fab:hover { color: #fff; filter: brightness(1.06); transform: translateY(-2px); }

/* 联系方式：三位联系人（一人一卡，电话可直接拨） */
.staff { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; margin-top: 24px; }
.staff__card {
  padding: 20px 22px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--r);
  box-shadow: var(--sh-sm);
  transition: border-color .18s ease, box-shadow .18s ease, transform .18s ease;
}
.staff__card:hover { border-color: var(--brand-line); box-shadow: var(--sh-cy); transform: translateY(-3px); }
.staff__role {
  margin: 0 0 6px;
  font-family: var(--mono);
  font-size: .7rem;
  font-weight: 700;
  letter-spacing: .12em;
  color: var(--brand-d);
  text-transform: uppercase;
}
.staff__name { margin: 0 0 10px; font-size: 1.16rem; font-weight: 750; color: var(--fg); }
.staff__tel {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--mono);
  font-size: 1.04rem;
  font-weight: 700;
  color: var(--fg);
}
.staff__tel:hover { color: var(--brand-d); }
.staff__tel .ico { width: 16px; height: 16px; color: var(--brand-d); }
.staff__wx {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: 8px 0 0;
  font-family: var(--mono);
  font-size: .92rem;
  color: var(--fg-2);
}
.staff__wx .ico { width: 15px; height: 15px; color: var(--fg-4); }
/* 联系区里只剩两张信息卡时排两列 */
.contact__grid--half { grid-template-columns: repeat(2, minmax(0, 1fr)); }
@media (max-width: 1080px) {
  .staff { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 640px) {
  .staff, .contact__grid--half { grid-template-columns: 1fr; }
}

/* ---------- 内页页头 ---------- */
.pagehead {
  position: relative;
  padding: 62px 0 52px;
  border-bottom: 1px solid var(--line-2);
}
/* 页头两栏：左标题正文 + 右速览卡，避免右侧留白 */
.pagehead__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 360px;
  gap: 40px 56px;
  align-items: start;
}
.pagehead__main > p { max-width: 52ch; }
.pagehead__acts { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 26px; }
.pagehead__side {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  padding: 20px 22px;
  box-shadow: var(--sh-sm);
}
.pagehead__side .panel__title { margin-bottom: 10px; }
.ph-course {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 9px 11px;
  border-radius: 12px;
  color: var(--fg);
  font-size: .94rem;
  font-weight: 650;
  transition: background .16s ease, color .16s ease;
}
.ph-course + .ph-course { margin-top: 2px; }
.ph-course:hover { background: var(--cy-soft); color: var(--brand-d); }
.ph-course__lvl {
  font-family: var(--mono);
  font-size: .68rem;
  font-weight: 700;
  padding: 3px 9px;
  border-radius: 999px;
  background: var(--cy-soft);
  color: var(--brand-d);
  flex: 0 0 auto;
}
.ph-course--teal .ph-course__lvl { background: var(--em-soft); color: #047857; }
.ph-course--amber .ph-course__lvl { background: var(--am-soft); color: #b45309; }
.ph-course--violet .ph-course__lvl { background: var(--vi-soft); color: #6d28d9; }
.ph-course--rose .ph-course__lvl { background: var(--ro-soft); color: #be123c; }
.ph-course em {
  margin-left: auto;
  font-style: normal;
  font-family: var(--mono);
  font-size: .76rem;
  color: var(--fg-4);
  white-space: nowrap;
}
.pagehead__note {
  margin: 14px 0 0;
  padding-top: 14px;
  border-top: 1px solid var(--line-2);
  font-size: .86rem;
  color: var(--fg-3);
  line-height: 1.6;
}
@media (max-width: 1080px) {
  .pagehead__grid { grid-template-columns: minmax(0, 1fr); gap: 26px; }
  .pagehead__main > p { max-width: none; }
  .pagehead__side { max-width: 520px; }
}
.pagehead h1 { margin-bottom: .35em; }
.pagehead p { color: var(--fg-2); max-width: 62ch; }
.crumb {
  margin-bottom: 18px;
  font-family: var(--mono);
  font-size: .74rem;
  letter-spacing: .08em;
  color: var(--fg-4);
  text-transform: uppercase;
}
/* 面包屑是 ol/li，要显式去掉编号并横排 */
.crumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  list-style: none;
  padding: 0;
  margin: 0;
}
.crumb li { margin: 0; }
.crumb li + li::before { content: "›"; margin-right: 8px; color: var(--fg-4); }
.crumb a { color: var(--fg-3); }
.crumb a:hover { color: var(--brand-d); }

/* ---------- 文档目录 ---------- */
.toc { position: sticky; top: 104px; }
.toc__title {
  margin: 0 0 14px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--line);
  font-family: var(--mono);
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .14em;
  color: var(--fg-3);
  text-transform: uppercase;
}
.toc ol { list-style: none; padding: 0; margin: 0; counter-reset: toc; }
.toc li { margin: .1em 0; }
.toc a {
  display: flex;
  gap: 10px;
  padding: 8px 12px;
  border-radius: 10px;
  color: var(--fg-2);
  font-size: .9rem;
}
.toc a::before {
  counter-increment: toc;
  content: counter(toc, decimal-leading-zero);
  font-family: var(--mono);
  font-size: .72rem;
  color: var(--fg-4);
}
.toc a:hover { background: var(--cy-soft); color: var(--brand-d); }
.toc-tools { display: flex; gap: 8px; margin-top: 16px; }

/* ---------- 提示条 ---------- */
.note {
  display: flex;
  gap: 14px;
  padding: 18px 22px;
  border-radius: var(--r);
  border: 1px solid #fde3b0;
  border-left: 4px solid var(--am);
  background: var(--am-soft);
  color: #7c5310;
  font-size: .94rem;
}
.note .ico { width: 18px; height: 18px; color: #d97706; margin-top: 3px; }
.note--brand { border-color: var(--brand-line); border-left-color: var(--brand); background: var(--cy-soft); color: #0c4a6e; }
.note--brand .ico { color: var(--brand-d); }

/* ---------- 页脚 ---------- */
.footer {
  margin-top: 0;
  padding: 64px 0 30px;
  border-top: 1px solid var(--line);
  background: var(--bg-2);
}
.footer__grid {
  display: grid;
  grid-template-columns: 1.7fr 1fr 1fr 1fr;
  gap: 44px;
  padding-bottom: 40px;
  border-bottom: 1px solid var(--line);
}
/* 品牌栏是整列容器（品牌 + 简介 + 联系方式），不是横排条 */
.footer__brand .brand { margin-bottom: 18px; }
.footer__brand > p { color: var(--fg-2); font-size: .93rem; margin: 0 0 12px; max-width: 46ch; }
.footer__brand .footer__note { color: var(--fg-3); font-size: .9rem; margin: 0; }
.footer__col h3, .footer__col h4 {
  margin: 0 0 16px;
  font-family: var(--mono);
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .14em;
  color: var(--fg-4);
  text-transform: uppercase;
}
.footer__col ul { list-style: none; padding: 0; margin: 0; }
.footer__col li { margin: 0; }
.footer__col a {
  display: block;
  padding: 5px 0;
  color: var(--fg-2);
  font-size: .93rem;
}
.footer__col a:hover { color: var(--brand-d); padding-left: 4px; }
.footer__note { color: var(--fg-3); font-size: .9rem; }
.footer__bot {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 24px;
  justify-content: space-between;
  padding-top: 26px;
  font-size: .85rem;
  color: var(--fg-4);
}
.footer__bot a { color: var(--fg-3); }

/* ---------- 工具类 ---------- */
.vh {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}
/* 「继续了解」小标题：顶部一条分隔线拉开与行动区的距离 */
.also__title {
  margin: 64px 0 20px;
  padding-top: 30px;
  border-top: 1px solid var(--line);
  font-family: var(--mono);
  font-size: .74rem;
  font-weight: 700;
  letter-spacing: .16em;
  color: var(--fg-4);
  text-transform: uppercase;
}
.also {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}
.also li { margin: 0; }
.also a {
  display: block;
  padding: 20px 24px;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background: #fff;
  box-shadow: var(--sh-sm);
  transition: border-color .18s ease, box-shadow .18s ease, transform .18s ease;
}
.also a:hover { border-color: var(--brand-line); box-shadow: var(--sh-cy); transform: translateY(-2px); }
.also b { display: block; margin-bottom: 4px; color: var(--fg); font-size: 1.02rem; }
.also span { color: var(--fg-3); font-size: .9rem; }

/* ---------- 打印 ---------- */
@media print {
  .topbar, .footer, .nav-toggle, .toc-tools, .contact-fab, .hero__visual { display: none; }
  body { background: #fff; color: #000; font-size: 11pt; background-image: none; }
  .section, .hero, .pagehead { background: #fff !important; padding: 12px 0; }
  .section + .section::before { display: none; }
  .card, .course, .qa__item, .panel, .tbl-wrap, .treegroup { border-color: #ccc; box-shadow: none; }
  a { color: #000; text-decoration: underline; }
  h1, h2, h3 { color: #000; }
}

/* ---------- 响应式 ---------- */
@media (max-width: 1420px) {
  .wrap { padding-inline: 30px; }
}
@media (max-width: 1240px) {
  .hero__grid { gap: 30px 42px; }
  .teacher { grid-template-columns: 300px minmax(0, 1fr); gap: 26px; }
  .split { grid-template-columns: minmax(0, 1fr) 320px; gap: 40px; }
  .grid--courses { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .course--wide { grid-column: span 2; }
  .footer__grid { grid-template-columns: 1fr 1fr 1fr; }
  .contact__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 1080px) {
  .section { padding: 76px 0; }
  .hero { padding: 58px 0 54px; }
  .hero__grid { grid-template-columns: 1fr; gap: 28px; }
  .hero__visual { order: 3; max-width: 640px; }
  .quick-wrap { order: 2; }
  .statbar { grid-template-columns: repeat(3, 1fr); margin-top: 34px; }
  .sec-head { grid-template-columns: 1fr; gap: 14px; margin-bottom: 36px; }
  .sec-head > p { grid-column: 1; }
  .sec-head .sec-label { padding-top: 0; }
  .teacher { grid-template-columns: 1fr; }
  .tcard { max-width: 520px; }
  .split, .rail, .doc { grid-template-columns: 1fr; gap: 36px; }
  .aside, .rail__side, .toc { position: static; }
  .toc ol { display: flex; flex-wrap: wrap; gap: 8px; }
  .toc a { border: 1px solid var(--line); border-radius: 999px; padding: 7px 15px; background: #fff; }
  .teamgrid { grid-template-columns: 1fr; }
  .sw { grid-template-columns: 1fr; }
  .contact { padding: 34px 28px; }
  .cta { padding: 38px 28px; }
}
@media (max-width: 860px) {
  body { font-size: 16px; }
  .nav-toggle { display: grid; }
  .nav {
    display: none;
    position: absolute;
    left: 0; right: 0; top: 72px;
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    background: #fff;
    border-bottom: 1px solid var(--line);
    padding: 12px 22px 20px;
    box-shadow: var(--sh);
  }
  .nav.is-open { display: flex; }
  .nav a { padding: 13px 14px; border-radius: 12px; }
  .nav__cta { margin: 10px 0 0; text-align: center; }
  .wrap { padding-inline: 20px; }
  .section { padding: 60px 0; }
  .grid--2, .grid--3, .grid--4, .grid--courses { grid-template-columns: 1fr; }
  .course--wide, .course--feature { grid-column: auto; }
  .statbar { grid-template-columns: repeat(2, 1fr); }
  .statbar > div { padding: 18px; }
  .statbar b { font-size: 1.6rem; }
  .card, .course, .teamcol { padding: 22px; }
  .qa__q { padding: 16px 18px; font-size: .96rem; }
  .qa__body, .qa__meta { padding-inline: 18px; }
  .footer { padding-top: 48px; }
  .footer__grid { grid-template-columns: 1fr; gap: 28px; }
  .contact-fab { right: 16px; bottom: 16px; padding: 12px 18px; font-size: .88rem; }
  .tbl thead th, .tbl tbody th, .tbl tbody td { padding: 12px 14px; }
  .contact__grid { grid-template-columns: 1fr; }
  .also { grid-template-columns: 1fr; }
}
@media (max-width: 480px) {
  .brand__sub { display: none; }
  .hero__acts .btn { width: 100%; }
  .statbar { grid-template-columns: 1fr; }
  .steps li { padding-left: 52px; }
  .cta__act .btn { width: 100%; }
}

/* ---------- 快速入口：编程学习（弹出平台选择） ---------- */
.tile-pop { position: relative; display: flex; flex: 1 1 auto; min-width: 0; }
.tile.is-primary {
  --tone: #fff;
  background: linear-gradient(120deg, #38bdf8, #6366f1 55%, #a855f7);
  border-color: transparent;
  color: #fff;
  font-weight: 750;
  box-shadow: 0 10px 26px rgba(56, 189, 248, .34);
}
.tile.is-primary .tile__ic { background: rgba(255, 255, 255, .22); color: #fff; }
.tile.is-primary:hover {
  background: linear-gradient(120deg, #38bdf8, #6366f1 55%, #a855f7);
  border-color: transparent;
  color: #fff;
  filter: brightness(1.06);
  box-shadow: 0 14px 32px rgba(99, 102, 241, .42);
}
.tile.is-primary::after { color: #fff; opacity: .85; }
.tile__caret { font-size: .78em; opacity: .85; line-height: 1; margin-left: -2px; }

.learnmenu {
  /* 用 fixed：首屏那段 overflow:hidden（裁装饰光晕用的）会把绝对定位的弹层切掉，
     所以位置由脚本按按钮的实际坐标计算，并随滚动/缩放重算 */
  position: fixed;
  z-index: 200;
  top: 0;
  left: 0;
  width: 400px;
  max-width: calc(100vw - 32px);
  padding: 16px;
  background: #fff;
  border: 1px solid var(--line, #e2ecf9);
  border-radius: var(--r-lg, 22px);
  box-shadow: 0 26px 60px rgba(16, 28, 51, .2), 0 4px 12px rgba(16, 28, 51, .06);
  text-align: left;
}
.learnmenu[hidden] { display: none; }
.learnmenu__title {
  margin: 0 0 10px;
  font-family: var(--mono, monospace);
  font-size: .7rem;
  font-weight: 700;
  letter-spacing: .14em;
  color: var(--ink-4, #9fb0c9);
  text-transform: uppercase;
}
.learnmenu__item {
  display: flex;
  align-items: center;
  gap: 12px;
  width: 100%;
  padding: 11px 12px;
  border: 0;
  border-radius: 13px;
  background: none;
  color: var(--ink, #16233a);
  font-family: inherit;
  text-align: left;
  cursor: pointer;
  transition: background .16s ease;
}
.learnmenu__item:hover { background: var(--brand-soft, #eaf2ff); }
.learnmenu__ic {
  width: 38px; height: 38px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  flex: 0 0 auto;
}
.learnmenu__ic .ico { width: 19px; height: 19px; }
.learnmenu__text { flex: 1 1 auto; min-width: 0; }
.learnmenu__text b { display: block; font-size: .95rem; font-weight: 700; }
.learnmenu__text i {
  display: block;
  margin-top: 2px;
  font-style: normal;
  font-size: .8rem;
  color: var(--ink-3, #6f84a6);
}
.learnmenu__go { color: var(--brand-d, #0284c7); font-weight: 700; }
.learnmenu__badge {
  padding: 3px 9px;
  border-radius: 999px;
  background: var(--amber-soft, #fff4dc);
  color: #b45309;
  font-family: var(--mono, monospace);
  font-size: .66rem;
  font-weight: 700;
  white-space: nowrap;
}
.learnmenu__item.is-soon { cursor: default; }
.learnmenu__item.is-soon:hover { background: #fff8ea; }
.learnmenu__notice {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  margin: 12px 0 0;
  padding: 12px 14px;
  border: 1px solid #fde3b0;
  border-radius: 13px;
  background: var(--amber-soft, #fff4dc);
  color: #7c5310;
  font-size: .86rem;
  line-height: 1.65;
}
.learnmenu__notice[hidden] { display: none; }
.learnmenu__notice .ico { width: 16px; height: 16px; color: #d97706; margin-top: 3px; flex: 0 0 auto; }
@keyframes learn-shake {
  0%, 100% { transform: none; }
  25% { transform: translateX(-3px); }
  75% { transform: translateX(3px); }
}
.learnmenu__item.is-shake { animation: learn-shake .4s ease; }

@media (prefers-reduced-motion: reduce) {
  .learnmenu__item.is-shake { animation: none; }
}

/* 首位的「编程学习」再突出一点：更宽 + 白色描边光环 */
.tile.is-primary { flex: 1.4 1 auto; box-shadow: 0 0 0 2px rgba(255, 255, 255, .55), 0 12px 28px rgba(99, 102, 241, .38); }
.tile.is-primary:hover { box-shadow: 0 0 0 2px rgba(255, 255, 255, .7), 0 16px 34px rgba(99, 102, 241, .46); }
@media (max-width: 1000px) { .tile.is-primary { flex: 0 1 auto; } }