@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+SC:wght@300;400;500;700&display=swap');

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

:root {
  --ink: #10131C;
  --ink-deep: #0A0D14;
  --amber: #E8863C;
  --amber-soft: rgba(232, 134, 60, .12);
  --paper: #F2EDE4;
  --line: rgba(242, 237, 228, .14);
  --glass: rgba(27, 32, 46, .55);
  --pad: clamp(16px, 4vw, 44px);
  --max: 1220px;
}

html {
  scroll-behavior: smooth;
  scroll-padding-bottom: 140px;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--ink);
  color: var(--paper);
  font-family: 'Noto Sans SC', system-ui, -apple-system, 'PingFang SC', 'Microsoft YaHei', sans-serif;
  font-size: 17px;
  font-weight: 400;
  line-height: 1.78;
  overflow-x: hidden;
  padding-bottom: 160px;
}

h1, h2, h3 { letter-spacing: -.01em; }

/* ---------- hero ---------- */
.hero {
  position: relative;
  min-height: 70vh;
  display: flex;
  flex-direction: column;
  justify-content: flex-start;
  overflow: hidden;
  isolation: isolate;
  perspective: 1px;
  padding: clamp(20px, 6vw, 44px) var(--pad) 0;
}

.sky {
  position: absolute;
  inset: -22% 0 0;
  z-index: -2;
  will-change: transform;
}

.orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(52px);
  opacity: .62;
}

.orb.a {
  width: 48vw; height: 48vw;
  min-width: 230px; min-height: 230px;
  top: -10%; left: -8%;
  background: radial-gradient(circle, rgba(232, 134, 60, .95), rgba(232, 134, 60, 0) 68%);
}

.orb.b {
  width: 38vw; height: 38vw;
  min-width: 190px; min-height: 190px;
  right: -12%; bottom: -16%;
  background: radial-gradient(circle, rgba(72, 92, 148, .9), rgba(72, 92, 148, 0) 70%);
}

.mesh {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--line) 1px, transparent 1px),
    linear-gradient(90deg, var(--line) 1px, transparent 1px);
  background-size: 68px 68px;
  opacity: .18;
  -webkit-mask-image: linear-gradient(to bottom, #000, transparent 88%);
  mask-image: linear-gradient(to bottom, #000, transparent 88%);
}

.grade {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(16, 19, 28, .2), rgba(16, 19, 28, .94));
}

.hero-copy {
  position: relative;
  margin-left: auto;
  max-width: 780px;
  text-align: right;
  padding-top: clamp(6px, 3vw, 26px);
}

.badge {
  display: inline-block;
  padding: 7px 14px;
  border: 1px solid rgba(232, 134, 60, .55);
  background: rgba(232, 134, 60, .1);
  color: var(--amber);
  font-size: 14px;
  letter-spacing: .2em;
  -webkit-backdrop-filter: blur(6px);
  backdrop-filter: blur(6px);
}

.hero h1 {
  margin: .38em 0 .22em;
  font-size: clamp(34px, 7.2vw, 66px);
  line-height: 1.14;
  font-weight: 700;
  letter-spacing: -.015em;
  text-wrap: balance;
}

.hero-lead {
  margin: 0 0 clamp(14px, 3vw, 26px);
  color: rgba(242, 237, 228, .7);
  font-size: 17px;
  line-height: 1.72;
}

.hero-frame {
  position: relative;
  margin-top: auto;
  height: 34vh;
  min-height: 170px;
  border-top: 1px solid var(--line);
  overflow: hidden;
  background:
    linear-gradient(120deg, rgba(232, 134, 60, .18), rgba(16, 19, 28, .72) 62%),
    var(--ink-deep);
}

.hero-frame img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(.92) contrast(1.06);
}

/* ---------- layout ---------- */
main { display: block; padding: 0 var(--pad); }

.wrap {
  max-width: var(--max);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 220px minmax(0, 1fr);
  gap: clamp(22px, 4vw, 54px);
  padding: clamp(34px, 6vw, 76px) 0;
}

.rail {
  position: sticky;
  top: 26px;
  align-self: start;
}

.rail h2 {
  margin: 0;
  font-size: 18px;
  font-weight: 700;
  letter-spacing: .16em;
  color: var(--amber);
}

.rail .subtitle {
  margin: 5px 0 18px;
  font-size: 14px;
  letter-spacing: .12em;
  color: rgba(242, 237, 228, .48);
}

.toc {
  list-style: none;
  margin: 0;
  padding: 0;
  border-left: 1px solid var(--line);
}

.toc a {
  display: block;
  padding: 10px 12px;
  margin-left: -1px;
  border-left: 2px solid transparent;
  color: rgba(242, 237, 228, .72);
  text-decoration: none;
  font-size: 16px;
  line-height: 1.4;
  transition: color .25s ease, border-color .25s ease, background .25s ease;
}

.toc a:hover,
.toc a:focus-visible {
  color: var(--paper);
  border-left-color: var(--amber);
  background: var(--amber-soft);
}

.story-wrap { min-width: 0; }

.story {
  counter-reset: chap;
  display: grid;
  gap: clamp(18px, 3vw, 30px);
}

.story > section {
  position: relative;
  counter-increment: chap;
  padding: clamp(22px, 4vw, 42px) clamp(18px, 3.6vw, 40px);
  background: var(--glass);
  border: 1px solid var(--line);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
  scroll-margin-top: 22px;
  will-change: transform, opacity;
}

.story > section::before {
  content: counter(chap, decimal-leading-zero);
  position: absolute;
  top: 4px;
  right: 14px;
  font-size: clamp(42px, 7.5vw, 68px);
  font-weight: 700;
  line-height: 1;
  color: rgba(232, 134, 60, .16);
  pointer-events: none;
}

.js .story > section {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity .72s ease, transform .72s cubic-bezier(.22, .7, .3, 1);
}

.js .story > section.in {
  opacity: 1;
  transform: none;
}

/* ---------- 正文排版 ---------- */
.story h2 {
  margin: 0 0 .1em;
  padding-right: 72px;
  font-size: clamp(22px, 3.2vw, 31px);
  line-height: 1.34;
  font-weight: 700;
}

.story h2::after {
  content: '';
  display: block;
  width: 46px;
  height: 2px;
  margin-top: 13px;
  background: var(--amber);
}

.story h3 {
  margin: 1.5em 0 .4em;
  font-size: 19px;
  font-weight: 500;
  color: var(--amber);
}

.story h2 + p,
.story .subtitle {
  margin-top: .9em;
  color: rgba(242, 237, 228, .62);
  font-size: 16px;
}

.story p {
  margin: 0 0 1.05em;
  color: rgba(242, 237, 228, .84);
}

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

.story strong { color: #FFF8EE; font-weight: 700; }

.story a {
  color: var(--amber);
  text-underline-offset: 3px;
}

.story ul,
.story ol {
  margin: 0 0 1.1em;
  padding-left: 1.3em;
}

.story li { margin: .34em 0; color: rgba(242, 237, 228, .84); }

.story li::marker { color: var(--amber); }

.story blockquote {
  margin: 1.2em 0;
  padding: 14px 18px;
  border-left: 2px solid var(--amber);
  background: var(--amber-soft);
  color: rgba(242, 237, 228, .88);
}

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

.story img {
  display: block;
  max-width: 100%;
  height: auto;
  margin: 1.1em 0;
  border: 1px solid var(--line);
}

.story figure { margin: 1.2em 0; }
.story figcaption { font-size: 15px; color: rgba(242, 237, 228, .55); margin-top: 8px; }

.story table {
  width: 100%;
  border-collapse: collapse;
  font-size: 16px;
  margin: 1.1em 0;
}

.story th,
.story td {
  border: 1px solid var(--line);
  padding: 10px 12px;
  text-align: left;
  vertical-align: top;
}

.story th { background: var(--amber-soft); color: var(--paper); }

.story hr {
  border: 0;
  border-top: 1px solid var(--line);
  margin: 1.6em 0;
}

/* ---------- 底部固定导航 ---------- */
.dock {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 60;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  padding: 8px 14px calc(8px + env(safe-area-inset-bottom, 0px));
  background: rgba(11, 14, 21, .84);
  border-top: 1px solid var(--line);
  -webkit-backdrop-filter: blur(18px);
  backdrop-filter: blur(18px);
}

.dock-top { display: contents; }

.dock-brand {
  order: 1;
  display: inline-flex;
  align-items: center;
  gap: 9px;
  min-height: 44px;
  padding: 0 8px;
  color: var(--paper);
  font-weight: 700;
  letter-spacing: .08em;
  text-decoration: none;
}

.mark {
  width: 11px;
  height: 11px;
  background: var(--amber);
  transform: rotate(45deg);
  display: block;
  flex: 0 0 auto;
}

.nm { font-size: 16px; }

.dock nav { order: 2; flex: 1 1 240px; min-width: 0; }

.dock nav ul {
  display: flex;
  gap: 2px;
  margin: 0;
  padding: 0;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}

.dock nav ul::-webkit-scrollbar { display: none; }

.dock nav a {
  display: flex;
  align-items: center;
  gap: 7px;
  min-height: 44px;
  padding: 0 10px;
  border-bottom: 2px solid transparent;
  color: rgba(242, 237, 228, .74);
  font-size: 16px;
  line-height: 1.3;
  white-space: nowrap;
  text-decoration: none;
  transition: color .2s ease, border-color .2s ease;
}

.dock nav a:hover,
.dock nav a:focus-visible {
  color: var(--paper);
  border-bottom-color: var(--amber);
}

.ico {
  width: 6px;
  height: 6px;
  flex: 0 0 auto;
  background: rgba(232, 134, 60, .8);
  transform: rotate(45deg);
}

.cta {
  order: 3;
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 16px;
  background: var(--amber);
  color: #14181F;
  font-size: 16px;
  font-weight: 700;
  white-space: nowrap;
  text-decoration: none;
  transition: background .2s ease;
}

.cta:hover,
.cta:focus-visible { background: #F59B54; }

.js .dock nav li {
  animation: rise .5s ease both;
  animation-delay: calc(var(--i, 0) * 45ms);
}

@keyframes rise {
  from { opacity: 0; transform: translateY(9px); }
  to { opacity: 1; transform: none; }
}

/* ---------- 页脚 ---------- */
footer {
  margin: clamp(44px, 8vw, 84px) var(--pad) 0;
  padding: 34px 0 42px;
  border-top: 1px solid var(--line);
}

.foot-grid {
  max-width: var(--max);
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
}

.fbrand {
  margin: 0;
  font-size: 17px;
  font-weight: 700;
  letter-spacing: .14em;
}

footer address {
  font-style: normal;
  font-size: 16px;
  line-height: 1.85;
  color: rgba(242, 237, 228, .58);
  word-break: break-all;
}

.flinks {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 4px;
}

.flinks a {
  display: inline-block;
  padding: 6px 0;
  color: rgba(242, 237, 228, .58);
  font-size: 16px;
  text-decoration: none;
}

.flinks a:hover,
.flinks a:focus-visible { color: var(--amber); }

.foot-end {
  max-width: var(--max);
  margin: 26px auto 0;
  padding-top: 16px;
  border-top: 1px solid var(--line);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  flex-wrap: wrap;
}

.copy {
  margin: 0;
  font-size: 15px;
  color: rgba(242, 237, 228, .45);
}

.totop { margin: 0; }

.totop a {
  display: inline-block;
  padding: 10px 0;
  color: var(--paper);
  font-size: 16px;
  text-decoration: none;
  border-bottom: 1px solid rgba(232, 134, 60, .6);
}

/* ---------- 响应式 ---------- */
@media (max-width: 900px) {
  .wrap {
    grid-template-columns: minmax(0, 1fr);
    gap: 22px;
  }

  .rail { position: static; }

  .rail h2 { font-size: 17px; }
  .rail .subtitle { margin: 4px 0 10px; }

  .toc {
    display: flex;
    gap: 8px;
    border-left: 0;
    padding-bottom: 4px;
    overflow-x: auto;
    scrollbar-width: none;
  }

  .toc::-webkit-scrollbar { display: none; }

  .toc a {
    margin-left: 0;
    padding: 10px 12px;
    border-left: 0;
    border-bottom: 2px solid transparent;
    white-space: nowrap;
  }

  .toc a:hover,
  .toc a:focus-visible {
    border-left-color: transparent;
    border-bottom-color: var(--amber);
  }
}

@media (max-width: 820px) {
  body { padding-bottom: 168px; }

  .dock {
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
  }

  .dock-top {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
  }

  .dock nav { order: 2; }

  .foot-grid { grid-template-columns: minmax(0, 1fr); gap: 18px; }
}

@media (max-width: 480px) {
  .hero { min-height: 68vh; }
  .hero-lead { font-size: 16px; }
  .badge { font-size: 13px; letter-spacing: .14em; }
  .nm { font-size: 15px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  .js .story > section {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .js .dock nav li { animation: none; }
}

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