/* ============================================================
   图灵编程官网 · 设计 token 与客户端保持一致（styles.css :root）
   ============================================================ */
:root {
  --bg: #f3f5fa;
  --bg-deep: #e8ecf5;
  --surface: #ffffff;
  --line: #e6eaf3;
  --ink: #182034;
  --ink-2: #5a6580;
  --ink-3: #939db4;
  --primary: #ed6a08;
  --primary-press: #d15a02;
  --primary-soft: #fff1e4;
  --structural: #3b6bff;
  --structural-pale: #e2eaff;
  --cat-blocks: #3b6deb;
  --cat-hardware: #ed6a08;
  --cat-code: #12a06a;
  --cat-quiz: #7b54d8;
  --r-xl: 24px;
  --r-lg: 18px;
  --r-md: 12px;
  --shadow-1: 0 1px 2px rgba(23,33,59,.04), 0 4px 14px rgba(23,33,59,.055);
  --shadow-2: 0 4px 10px rgba(23,33,59,.06), 0 18px 42px rgba(23,33,59,.1);
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --dur-move: 500ms;
  --dur-fade: 300ms;
  --font: "Manrope", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1 !important; transform: none !important; transition: none !important; }
  .ide-code span { animation: none !important; }
}
body {
  margin: 0;
  font-family: var(--font);
  background: var(--bg);
  color: var(--ink);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-wrap: pretty;
}
h1, h2, h3 { text-wrap: balance; margin: 0; letter-spacing: -0.01em; }
p { margin: 0; }
a { color: inherit; text-decoration: none; }
.wrap { max-width: 1180px; margin: 0 auto; padding: 0 24px; }
:focus-visible { outline: 3px solid rgba(59,107,255,.45); outline-offset: 2px; border-radius: 4px; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 8px 16px; border-radius: 999px; border: 0;
  font: 600 15px/24px var(--font); cursor: pointer;
  transition: transform var(--dur-fade) var(--ease), background var(--dur-fade) var(--ease), box-shadow var(--dur-fade) var(--ease);
}
.btn:active { transform: scale(0.98) translateY(1px); }
.btn-primary { background: var(--primary); color: #fff; box-shadow: 0 6px 18px rgba(237,106,8,.28); }
.btn-primary:hover { background: var(--primary-press); }
.btn-ghost { background: var(--surface); color: var(--ink); box-shadow: var(--shadow-1); }
.btn-ghost:hover { background: #fff; box-shadow: var(--shadow-2); }
.btn-lg { padding: 12px 24px; font-size: 16px; }
.btn-block { width: 100%; }
.btn[disabled] { opacity: .6; cursor: default; transform: none; }

/* ---------- 导航 ---------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(243,245,250,.82);
  backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
}
.nav-inner { display: flex; align-items: center; gap: 28px; height: 64px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 18px; }
.brand-mark { width: 30px; height: 30px; }
.nav-links { display: flex; gap: 26px; margin-left: auto; font-size: 15px; color: var(--ink-2); }
.nav-links a { padding: 6px 2px; border-radius: 6px; transition: color var(--dur-fade) var(--ease); }
.nav-links a:hover { color: var(--ink); }
.nav-cta { margin-left: 4px; }
.nav-toggle { display: none; margin-left: auto; width: 40px; height: 40px; border: 0; background: none; cursor: pointer; padding: 8px; }
.nav-toggle span { display: block; height: 2px; margin: 5px 0; background: var(--ink); border-radius: 2px; transition: transform var(--dur-fade) var(--ease), opacity var(--dur-fade) var(--ease); }
.nav-sheet { display: none; }
.nav-open .nav-toggle span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-open .nav-toggle span:nth-child(2) { opacity: 0; }
.nav-open .nav-toggle span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero { position: relative; overflow: hidden; padding: 84px 0 64px; }
.hero-shapes { position: absolute; inset: 0; pointer-events: none; }
.shape { position: absolute; border-radius: 50%; filter: blur(2px); }
.s1 { width: 420px; height: 420px; left: -140px; top: -120px; background: var(--primary-soft); }
.s2 { width: 300px; height: 300px; right: -90px; bottom: -60px; background: var(--structural-pale); }
.s3 { width: 120px; height: 120px; left: 46%; top: 8%; background: var(--bg-deep); }
.hero-grid { position: relative; display: grid; grid-template-columns: 1.05fr .95fr; gap: 56px; align-items: center; }
.hero-eyebrow {
  display: inline-block; padding: 4px 14px; border-radius: 999px;
  background: var(--primary-soft); color: var(--primary); font-weight: 600; font-size: 14px;
  margin-bottom: 20px;
}
.hero h1 { font-size: clamp(30px, 4.4vw, 50px); line-height: 1.22; font-weight: 700; }
.hero h1 em { font-style: normal; color: var(--primary); }
.hero-sub { margin: 22px 0 30px; font-size: 17px; color: var(--ink-2); max-width: 34em; }
.hero-cta { display: flex; gap: 14px; flex-wrap: wrap; }
.hero-points { display: flex; gap: 22px; flex-wrap: wrap; margin: 30px 0 0; padding: 0; list-style: none; color: var(--ink-2); font-size: 14px; }
.hero-points li { display: flex; align-items: center; gap: 7px; }
.hero-points li::before {
  content: ""; width: 7px; height: 7px; border-radius: 2px; background: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-soft);
}

/* Hero IDE 卡片（纯 CSS 手绘客户端既视感） */
.ide-card {
  background: var(--surface); border-radius: var(--r-xl); box-shadow: var(--shadow-2);
  overflow: hidden; border: 1px solid var(--line);
  transform: rotate(1.2deg);
}
.ide-bar { display: flex; align-items: center; gap: 7px; padding: 12px 16px; background: var(--bg-deep); }
.ide-bar i { width: 10px; height: 10px; border-radius: 50%; background: #d5dcea; }
.ide-bar i:first-child { background: var(--primary); }
.ide-bar span { margin-left: 8px; font-size: 12px; color: var(--ink-3); }
.ide-body { display: grid; grid-template-columns: 1.1fr .9fr; gap: 14px; padding: 16px; }
.ide-blocks { background: #f7f8fc; border-radius: var(--r-md); padding: 12px; }
.blk {
  border-radius: 10px; color: #fff; font-size: 12.5px; font-weight: 600;
  padding: 8px 12px; margin-bottom: 8px; width: fit-content; min-width: 130px;
}
.blk b { font-weight: 800; }
.b-start { background: var(--cat-quiz); }
.b-move { background: var(--cat-blocks); }
.b-loop { background: var(--cat-code); }
.b-inner { background: rgba(255,255,255,.22); margin: 8px 0 0 14px; box-shadow: inset 0 0 0 1px rgba(255,255,255,.25); }
.ide-code {
  background: #1c2438; color: #dce4f5; border-radius: var(--r-md); padding: 12px;
  font: 12px/1.7 var(--font); font-family: ui-monospace, "SF Mono", Menlo, monospace;
  white-space: pre-wrap; min-height: 150px;
}
.ide-code .kw { color: #f0a500; } .ide-code .fn { color: #7fd4ff; } .ide-code .num { color: #9be8b8; }
.ide-out {
  display: flex; gap: 12px; align-items: center; padding: 12px 16px; border-top: 1px dashed var(--line);
  font-size: 13px; color: var(--ink-2);
}
.ide-out b { color: var(--success); font-weight: 700; }

/* ---------- 数据条 ---------- */
.stats { padding: 8px 0 40px; }
.stats-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px;
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--r-xl);
  box-shadow: var(--shadow-1); padding: 26px 34px;
}
.stat { text-align: center; }
.stat b { display: block; font-size: 30px; font-weight: 800; color: var(--primary); font-variant-numeric: tabular-nums; }
.stat span { font-size: 13.5px; color: var(--ink-2); }

/* ---------- 通用 section ---------- */
.section { padding: 72px 0; }
.section-tint { background: var(--surface); border-block: 1px solid var(--line); }
.sec-head { max-width: 620px; margin-bottom: 40px; }
.sec-head h2 { font-size: clamp(24px, 3vw, 34px); }
.sec-head p { margin-top: 12px; color: var(--ink-2); font-size: 16px; }
.sec-foot { margin-top: 26px; color: var(--ink-2); font-size: 15px; }
.sec-foot b { color: var(--ink); }

/* ---------- 课程 ---------- */
.course-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.course-card {
  display: flex; flex-direction: column; gap: 12px;
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--r-lg);
  padding: 20px; box-shadow: var(--shadow-1); min-height: 148px;
  transition: transform var(--dur-move) var(--ease), box-shadow var(--dur-move) var(--ease);
}
.course-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-2); }
.course-top { display: flex; align-items: center; gap: 10px; }
.course-glyph {
  width: 42px; height: 42px; border-radius: 12px; color: #fff; font-weight: 800;
  display: grid; place-items: center; font-size: 15px; letter-spacing: -.5px;
}
.course-type {
  font-size: 12px; font-weight: 700; padding: 3px 10px; border-radius: 999px; color: #fff;
}
.course-card h3 { font-size: 17px; }
.course-card p { font-size: 13.5px; color: var(--ink-2); flex: 1; }
.course-meta { display: flex; gap: 14px; font-size: 12.5px; color: var(--ink-3); }
.course-meta b { color: var(--ink-2); font-weight: 600; }

/* ---------- 特色 ---------- */
.feature-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.feature {
  background: var(--bg); border: 1px solid var(--line); border-radius: var(--r-lg); padding: 24px 22px;
}
.fi {
  width: 48px; height: 48px; border-radius: 14px; display: grid; place-items: center; margin-bottom: 16px;
}
.fi svg { width: 26px; height: 26px; }
.fi-blocks { background: var(--structural-pale); color: var(--cat-blocks); }
.fi-ai { background: var(--primary-soft); color: var(--primary); }
.fi-hw { background: #e2f6ee; color: var(--cat-code); }
.fi-share { background: #f1ecfc; color: var(--cat-quiz); }
.feature h3 { font-size: 16.5px; margin-bottom: 8px; }
.feature p { font-size: 14px; color: var(--ink-2); }

/* ---------- 作品墙 ---------- */
.works-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.work-card {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--r-lg);
  overflow: hidden; box-shadow: var(--shadow-1);
  transition: transform var(--dur-move) var(--ease), box-shadow var(--dur-move) var(--ease);
}
.work-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-2); }
.work-cover { height: 130px; position: relative; }
.work-cover::after {
  content: ""; position: absolute; inset: 0;
  background: repeating-linear-gradient(45deg, rgba(255,255,255,.08) 0 10px, transparent 10px 20px);
}
.work-cover span {
  position: absolute; left: 14px; bottom: 10px; color: #fff; font-weight: 700; font-size: 17px;
  text-shadow: 0 2px 8px rgba(20,26,45,.35);
}
.work-bar {
  display: flex; align-items: center; gap: 10px; padding: 12px 14px; font-size: 13px; color: var(--ink-2);
}
.avatar {
  width: 26px; height: 26px; border-radius: 8px; display: grid; place-items: center;
  color: #fff; font-size: 12.5px; font-weight: 700; flex: none;
}
.work-bar .likes { margin-left: auto; display: flex; align-items: center; gap: 4px; }
.work-bar .likes i { width: 14px; height: 14px; border-radius: 50%; background: var(--primary-soft); position: relative; }
.work-bar .likes i::after {
  content: ""; position: absolute; inset: 4px; border-radius: 50%; background: var(--primary);
}
.work-mine {
  margin-left: 8px; font-size: 11px; color: var(--primary); background: var(--primary-soft);
  padding: 2px 8px; border-radius: 999px; font-weight: 700;
}

/* ---------- 学习榜 ---------- */
.rank-wrap { max-width: 760px; }
.rank-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 10px; }
.rank-row {
  display: flex; align-items: center; gap: 14px; padding: 12px 18px;
  background: var(--bg); border: 1px solid var(--line); border-radius: var(--r-md);
  font-size: 15px;
}
.rank-row.me { background: var(--primary-soft); border-color: #f4c79e; }
.rank-no { width: 28px; font-weight: 800; color: var(--ink-3); font-variant-numeric: tabular-nums; }
.rank-row:nth-child(1) .rank-no { color: var(--primary); }
.rank-row:nth-child(2) .rank-no { color: var(--structural); }
.rank-row:nth-child(3) .rank-no { color: var(--cat-code); }
.rank-name { font-weight: 600; }
.rank-tag {
  margin-left: 6px; font-size: 11px; color: var(--primary); background: #fff;
  border: 1px solid #f4c79e; padding: 1px 8px; border-radius: 999px; font-weight: 700;
}
.rank-coins { margin-left: auto; font-weight: 700; color: var(--primary); font-variant-numeric: tabular-nums; }
.rank-coins small { font-weight: 500; color: var(--ink-3); margin-left: 2px; }

/* ---------- 申请内测 ---------- */
.apply-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center; }
.apply-copy h2 { font-size: clamp(24px, 3vw, 34px); }
.apply-copy p { margin-top: 14px; color: var(--ink-2); }
.apply-points { margin: 22px 0 0; padding: 0; list-style: none; color: var(--ink-2); font-size: 15px; display: grid; gap: 10px; }
.apply-points li { display: flex; gap: 10px; align-items: center; }
.apply-points li::before {
  content: ""; flex: none; width: 8px; height: 8px; border-radius: 3px; background: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-soft);
}
.apply-form {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--r-xl);
  box-shadow: var(--shadow-2); padding: 28px; display: grid; gap: 16px;
}
.apply-form label { display: grid; gap: 6px; font-size: 14px; font-weight: 600; }
.apply-form label small { color: var(--ink-3); font-weight: 500; }
.apply-form input, .apply-form select, .apply-form textarea {
  font: 400 15px/1.5 var(--font); color: var(--ink);
  border: 1px solid var(--line); border-radius: var(--r-md); padding: 10px 14px; background: var(--bg);
  transition: border-color var(--dur-fade) var(--ease), box-shadow var(--dur-fade) var(--ease);
}
.apply-form input:focus, .apply-form select:focus, .apply-form textarea:focus {
  outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px rgba(237,106,8,.15);
}
.apply-form input.err { border-color: var(--cat-quiz); }
.field-err { color: #b03232; font-size: 12.5px; font-weight: 500; min-height: 16px; font-style: normal; }
.apply-result { font-size: 14px; font-weight: 600; color: var(--cat-code); min-height: 20px; }
.apply-result.bad { color: #b03232; }
.apply-privacy { font-size: 12px; color: var(--ink-3); }

/* ---------- FAQ ---------- */
.faq-wrap { max-width: 760px; }
.faq-list { display: grid; gap: 12px; }
.faq-list details {
  background: var(--bg); border: 1px solid var(--line); border-radius: var(--r-md); padding: 16px 20px;
}
.faq-list summary {
  cursor: pointer; font-weight: 600; font-size: 15.5px; list-style: none; position: relative; padding-right: 28px;
}
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after {
  content: ""; position: absolute; right: 4px; top: 8px; width: 9px; height: 9px;
  border-right: 2px solid var(--ink-3); border-bottom: 2px solid var(--ink-3);
  transform: rotate(45deg); transition: transform var(--dur-fade) var(--ease);
}
.faq-list details[open] summary::after { transform: rotate(225deg); top: 12px; }
.faq-list details p { margin-top: 10px; color: var(--ink-2); font-size: 14.5px; }

/* ---------- Footer ---------- */
.footer { background: var(--surface); border-top: 1px solid var(--line); padding: 40px 0; margin-top: 24px; }
.footer-inner { display: flex; gap: 32px; align-items: flex-start; flex-wrap: wrap; }
.footer-brand { display: flex; gap: 12px; align-items: center; }
.footer-brand p { font-size: 13px; color: var(--ink-3); }
.footer-links { margin-left: auto; display: flex; gap: 22px; font-size: 14px; color: var(--ink-2); flex-wrap: wrap; }
.footer-links a:hover { color: var(--ink); }
.footer-note { width: 100%; font-size: 12.5px; color: var(--ink-3); border-top: 1px solid var(--line); padding-top: 18px; margin-top: 6px; }

/* ---------- 骨架屏 ---------- */
.skeleton {
  border-radius: var(--r-lg);
  background: linear-gradient(100deg, #eef1f7 40%, #f7f9fc 50%, #eef1f7 60%);
  background-size: 200% 100%;
  animation: shimmer 1.4s linear infinite;
}
@keyframes shimmer { to { background-position: -200% 0; } }
.sk-card { height: 148px; }
.sk-work { height: 190px; }
.sk-rank { height: 54px; }

/* ---------- 滚动浮现（渐进增强：html.js 才隐藏待浮现元素，无 JS 全可见） ---------- */
html.js .reveal { opacity: 0; transform: translateY(18px); transition: opacity .7s var(--ease), transform .7s var(--ease); }
html.js .reveal.in { opacity: 1; transform: none; }

/* ---------- 响应式 ---------- */
@media (max-width: 960px) {
  .hero { padding: 56px 0 48px; }
  .hero-grid { grid-template-columns: 1fr; gap: 40px; }
  .ide-card { transform: none; max-width: 560px; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); padding: 22px; }
  .course-grid, .works-grid { grid-template-columns: repeat(2, 1fr); }
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .apply-grid { grid-template-columns: 1fr; gap: 32px; }
}
@media (max-width: 640px) {
  .hero h1 br { display: none; } /* 小屏让标题自然换行 */
  .nav-links, .nav-cta { display: none; }
  .nav-toggle { display: block; }
  .nav-open .nav-sheet {
    display: grid; gap: 4px; padding: 10px 24px 18px;
    border-top: 1px solid var(--line); background: var(--bg);
  }
  .nav-sheet a { padding: 10px 0; font-size: 16px; font-weight: 600; }
  .nav-sheet .btn { margin-top: 8px; justify-self: start; }
  .course-grid, .works-grid, .feature-grid { grid-template-columns: 1fr; }
  .ide-body { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .section { padding: 52px 0; }
}