@import url('https://fonts.googleapis.com/css2?family=Exo:wght@300;400;500;600;700&family=Roboto+Mono:wght@300;400;500;700&display=swap');

:root {
  --ink: #1B1F3B;
  --ink-2: #232A52;
  --ink-3: #141830;
  --coral: #FF4D3D;
  --sun: #FFD447;
  --text: #E9ECF8;
  --dim: #A7AECD;
  --line: rgba(255, 255, 255, 0.16);
  --r-card: 28px;
  --r-mid: 16px;
  --r-sm: 10px;
  --font-body: "Exo", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
  --font-mono: "Roboto Mono", "PingFang SC", "Microsoft YaHei", ui-monospace, monospace;
  --rail: 100px;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--ink);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.75;
  font-weight: 400;
  letter-spacing: 0.01em;
}

img { max-width: 100%; }

a { color: var(--sun); text-decoration: none; }

a:hover { color: var(--coral); }

a:focus-visible,
button:focus-visible,
input:focus-visible {
  outline: 3px solid var(--sun);
  outline-offset: 2px;
}

h1, h2, h3 {
  font-weight: 700;
  line-height: 1.3;
  letter-spacing: 0.01em;
}

.skip {
  position: absolute;
  left: 8px;
  top: -60px;
  z-index: 200;
  padding: 12px 18px;
  background: var(--sun);
  color: var(--ink);
  border-radius: var(--r-sm);
  font-weight: 700;
}

.skip:focus { top: 8px; color: var(--ink); }

/* ---------- 左侧竖栏 ---------- */
.side {
  position: fixed;
  left: 0;
  top: 0;
  bottom: 0;
  width: var(--rail);
  z-index: 60;
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 14px 8px 20px;
  background: var(--ink-3);
  border-right: 2px solid var(--coral);
  overflow-y: auto;
  overflow-x: hidden;
}

.brand {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 52px;
  height: 52px;
  margin: 0 auto;
  border: 2px solid var(--sun);
  border-radius: 14px;
  background: var(--sun);
  color: var(--ink);
  font-weight: 700;
  flex: 0 0 auto;
}

.brand:hover { background: var(--coral); border-color: var(--coral); color: var(--ink); }

.brand-glyph { font-size: 24px; line-height: 1; }

.brand-img { width: 34px; height: 34px; object-fit: contain; }

.rail { flex: 1 1 auto; }

.navlist {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.grp { position: relative; }

.navlist > li > a {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 52px;
  padding: 10px 4px;
  border: 2px solid transparent;
  border-radius: var(--r-mid);
  color: var(--text);
  font-size: 16px;
  font-weight: 600;
  text-align: center;
  line-height: 1.35;
  transition: background 160ms ease, color 160ms ease, border-color 160ms ease;
}

.navlist > li > a:hover,
.navlist > li:focus-within > a {
  background: var(--ink-2);
  border-color: var(--sun);
  color: var(--sun);
}

.sub {
  display: none;
  list-style: none;
  margin: 0;
  padding: 8px;
  position: absolute;
  left: calc(100% + 8px);
  top: 0;
  min-width: 178px;
  background: var(--ink-2);
  border: 2px solid var(--sun);
  border-radius: var(--r-mid);
  z-index: 80;
}

.grp:hover .sub,
.grp:focus-within .sub { display: block; }

.sub a {
  display: flex;
  align-items: center;
  min-height: 44px;
  padding: 8px 12px;
  border-radius: var(--r-sm);
  color: var(--text);
  font-size: 16px;
  font-weight: 500;
}

.sub a:hover { background: var(--sun); color: var(--ink); }

.search {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding-top: 12px;
  border-top: 2px dashed var(--line);
  flex: 0 0 auto;
}

.search-label {
  font-family: var(--font-mono);
  font-size: 16px;
  color: var(--dim);
  text-align: center;
}

.search-field {
  width: 100%;
  min-height: 40px;
  padding: 8px 10px;
  border: 2px solid var(--line);
  border-radius: var(--r-sm);
  background: var(--ink-2);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 16px;
}

.search-field::placeholder { color: var(--dim); }

.search-btn {
  min-height: 44px;
  border: 2px solid var(--sun);
  border-radius: var(--r-sm);
  background: transparent;
  color: var(--sun);
  font-family: var(--font-body);
  font-size: 16px;
  font-weight: 700;
  cursor: pointer;
  transition: background 160ms ease, color 160ms ease;
}

.search-btn:hover { background: var(--sun); color: var(--ink); }

/* ---------- 主区 ---------- */
main {
  margin-left: var(--rail);
  display: block;
}

section[id] { scroll-margin-top: 32px; }

.hero {
  position: relative;
  min-height: 100vh;
  min-height: 100svh;
  display: grid;
  place-items: center;
  padding: 96px 24px 120px;
  text-align: center;
  overflow: hidden;
  background: var(--ink-2);
  border-bottom: 4px solid var(--coral);
  border-bottom-left-radius: 120px;
  border-bottom-right-radius: 120px;
}

.hero-img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.42;
}

.hero-inner {
  position: relative;
  z-index: 3;
  max-width: 760px;
}

.eyebrow {
  display: inline-block;
  margin: 0 0 18px;
  padding: 6px 16px;
  border: 2px solid var(--sun);
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 16px;
  color: var(--sun);
  background: var(--ink);
}

.hero h1 {
  margin: 0 0 20px;
  font-size: clamp(2rem, 6vw, 4rem);
  letter-spacing: 0.01em;
}

.hero-lead {
  margin: 0 auto 30px;
  max-width: 620px;
  font-size: 18px;
  color: var(--text);
}

.hero-cta {
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  justify-content: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 12px 26px;
  border-radius: 999px;
  border: 3px solid var(--sun);
  font-size: 17px;
  font-weight: 700;
  transition: background 160ms ease, color 160ms ease, border-color 160ms ease;
}

.btn-solid { background: var(--sun); color: var(--ink); }

.btn-solid:hover { background: var(--coral); border-color: var(--coral); color: var(--ink); }

.btn-line { background: transparent; color: var(--sun); }

.btn-line:hover { background: var(--sun); color: var(--ink); }

.chip {
  position: absolute;
  z-index: 2;
  padding: 8px 16px;
  border: 2px solid var(--ink);
  border-radius: 999px;
  background: var(--coral);
  color: #fff;
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 500;
  animation: bob 4s ease-in-out infinite alternate;
}

.chip-a { top: 18%; left: 8%; }

.chip-b { top: 30%; right: 9%; background: var(--sun); color: var(--ink); animation-delay: 0.8s; }

.chip-c { bottom: 22%; left: 14%; background: var(--ink); color: var(--sun); border-color: var(--sun); animation-delay: 1.6s; }

@keyframes bob {
  from { transform: translateY(-8px); }
  to { transform: translateY(8px); }
}

.wrap {
  max-width: 1200px;
  margin: 0 auto;
  padding: 64px 28px 88px;
  display: grid;
  grid-template-columns: minmax(0, 1fr) 320px;
  gap: 30px;
  align-items: start;
}

.body-col { min-width: 0; }

.prose {
  display: block;
  padding: 34px 30px 40px;
  border: 2px solid var(--line);
  border-radius: var(--r-card);
  background: var(--ink-2);
}

.prose > section { display: block; }

.prose > section + section {
  margin-top: 46px;
  padding-top: 42px;
  border-top: 2px dashed var(--line);
}

.prose h2 {
  margin: 0 0 18px;
  padding-left: 16px;
  border-left: 9px solid var(--sun);
  font-size: clamp(1.45rem, 3.2vw, 2rem);
}

.prose h3 {
  margin: 28px 0 12px;
  font-size: 1.2rem;
  color: var(--sun);
}

.prose p { margin: 0 0 18px; }

.prose small {
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: 16px;
  letter-spacing: 0.08em;
  color: var(--sun);
}

.prose ul,
.prose ol {
  margin: 0 0 20px;
  padding-left: 24px;
}

.prose li { margin-bottom: 10px; }

.prose strong { color: var(--sun); }

.prose blockquote {
  margin: 0 0 20px;
  padding: 16px 20px;
  border: 2px solid var(--coral);
  border-radius: var(--r-mid);
  background: var(--ink);
}

.prose blockquote p:last-child { margin-bottom: 0; }

.prose table {
  width: 100%;
  border-collapse: collapse;
  margin: 0 0 20px;
  font-size: 16px;
}

.prose th,
.prose td {
  border: 2px solid var(--line);
  padding: 10px 12px;
  text-align: left;
}

.prose th { background: var(--ink); color: var(--sun); }

.prose a { text-decoration: underline; text-underline-offset: 3px; }

.prose img { border-radius: var(--r-mid); }

/* ---------- 侧栏 ---------- */
.side-col {
  position: sticky;
  top: 26px;
  padding: 24px 22px 26px;
  border: 2px solid var(--sun);
  border-radius: var(--r-card);
  background: var(--ink-2);
}

.side-col small {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: 16px;
  letter-spacing: 0.08em;
  color: var(--coral);
}

.side-col h2 {
  margin: 0 0 12px;
  font-size: 1.25rem;
}

.aside-note {
  margin: 0 0 16px;
  font-size: 16px;
  color: var(--dim);
}

.aside-list {
  list-style: none;
  margin: 0 0 16px;
  padding: 0;
}

.aside-list a {
  display: flex;
  align-items: center;
  min-height: 42px;
  padding: 6px 4px;
  border-bottom: 1px solid var(--line);
  color: var(--text);
  font-size: 16px;
  font-weight: 500;
}

.aside-list a:hover { color: var(--sun); }

.aside-tip {
  margin: 0;
  padding-top: 14px;
  border-top: 2px solid var(--coral);
  font-size: 16px;
  color: var(--dim);
}

.is-hit { outline: 3px solid var(--coral); outline-offset: 6px; border-radius: var(--r-mid); }

/* ---------- 页脚 ---------- */
.foot {
  margin-left: var(--rail);
  padding: 46px 28px 26px;
  border-top: 4px solid var(--sun);
  background: var(--ink-3);
}

.f-top {
  max-width: 1180px;
  margin: 0 auto 28px;
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1.4fr);
  gap: 32px;
}

.f-logo {
  margin: 0 0 10px;
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--sun);
}

.f-desc {
  margin: 0 0 20px;
  font-size: 16px;
  color: var(--dim);
  max-width: 40ch;
}

.sub-form { max-width: 400px; }

.sub-label {
  display: block;
  margin-bottom: 8px;
  font-size: 16px;
  color: var(--text);
}

.sub-row { display: flex; gap: 8px; flex-wrap: wrap; }

.sub-field {
  flex: 1 1 160px;
  min-height: 44px;
  padding: 9px 12px;
  border: 2px solid var(--line);
  border-radius: var(--r-sm);
  background: var(--ink-2);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 16px;
}

.sub-field::placeholder { color: var(--dim); }

.sub-btn {
  min-height: 44px;
  padding: 9px 22px;
  border: 2px solid var(--coral);
  border-radius: var(--r-sm);
  background: var(--coral);
  color: #fff;
  font-family: var(--font-body);
  font-size: 16px;
  font-weight: 700;
  cursor: pointer;
  transition: background 160ms ease, color 160ms ease;
}

.sub-btn:hover { background: var(--sun); border-color: var(--sun); color: var(--ink); }

.sub-tip {
  margin: 8px 0 0;
  min-height: 24px;
  font-size: 16px;
  color: var(--sun);
}

.f-cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
}

.fcol { margin: 0; }

.fcol dt {
  margin-bottom: 8px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--coral);
  font-family: var(--font-mono);
  font-size: 16px;
  color: var(--sun);
}

.fcol dd { margin: 0; }

.fcol dd a {
  display: flex;
  align-items: center;
  min-height: 40px;
  padding: 4px 0;
  color: var(--text);
  font-size: 16px;
}

.fcol dd a:hover { color: var(--sun); }

.copy {
  margin: 0 auto;
  max-width: 1180px;
  padding-top: 18px;
  border-top: 2px dashed var(--line);
  text-align: center;
  font-size: 16px;
  color: var(--dim);
}

.copy-sub { margin-top: 6px; border-top: 0; padding-top: 0; }

/* ---------- 移动端 ---------- */
@media (max-width: 1000px) {
  .side {
    right: 0;
    bottom: auto;
    width: auto;
    flex-direction: row;
    align-items: center;
    gap: 10px;
    padding: 8px 10px;
    border-right: 0;
    border-bottom: 2px solid var(--coral);
    overflow: visible;
  }

  .brand {
    width: 44px;
    height: 44px;
    margin: 0;
    border-radius: var(--r-sm);
  }

  .brand-glyph { font-size: 20px; }

  .rail { flex: 1 1 auto; min-width: 0; }

  .navlist {
    flex-direction: row;
    gap: 8px;
    overflow-x: auto;
    padding-bottom: 2px;
    scrollbar-width: thin;
  }

  .navlist > li { flex: 0 0 auto; }

  .grp { display: flex; gap: 8px; }

  .navlist > li > a {
    min-height: 44px;
    padding: 8px 14px;
    white-space: nowrap;
    font-size: 16px;
  }

  .sub {
    display: flex;
    gap: 8px;
    position: static;
    padding: 0;
    border: 0;
    background: transparent;
    min-width: 0;
  }

  .sub a {
    min-height: 44px;
    padding: 8px 14px;
    white-space: nowrap;
    border: 2px solid var(--line);
  }

  .search {
    flex-direction: row;
    align-items: center;
    gap: 6px;
    padding-top: 0;
    border-top: 0;
    flex: 0 0 auto;
  }

  .search-label { display: none; }

  .search-field { width: 124px; }

  .search-btn { padding: 0 14px; }

  main { margin-left: 0; }

  .hero {
    padding: 92px 20px 96px;
    border-bottom-left-radius: 56px;
    border-bottom-right-radius: 56px;
  }

  .wrap {
    grid-template-columns: minmax(0, 1fr);
    padding: 40px 16px 64px;
    gap: 24px;
  }

  .prose { padding: 24px 18px 30px; }

  .side-col { position: static; }

  .foot { margin-left: 0; padding: 36px 16px 22px; }

  .f-top { grid-template-columns: minmax(0, 1fr); gap: 24px; }

  .f-cols { grid-template-columns: repeat(2, minmax(0, 1fr)); }

  section[id] { scroll-margin-top: 84px; }

  .chip-c { display: none; }
}

@media (max-width: 420px) {
  .chip { font-size: 15px; padding: 6px 12px; }
  .chip-a { left: 4%; }
  .chip-b { right: 4%; }
  .search-field { width: 96px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .chip { animation: none; }
  * { transition: none !important; }
}

button[aria-expanded]{min-width:44px;min-height:44px}