@import url('https://fonts.googleapis.com/css2?family=Anton&family=Epilogue:wght@400;500;600;700&display=swap');

:root {
  --paper: #fdfbf7;
  --wash: #f5f5f5;
  --ink: #1a1a1a;
  --line: #e0e0e0;
  --mute: #5b5b5b;
}

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

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

body {
  margin: 0;
  padding-bottom: 168px;
  background: var(--paper);
  color: var(--ink);
  font-family: 'Epilogue', 'Songti SC', 'SimSun', Georgia, serif;
  font-size: 17px;
  line-height: 1.78;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 80;
  pointer-events: none;
  opacity: .32;
  background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='140' height='140'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='3'/></filter><rect width='140' height='140' filter='url(%23n)' opacity='0.4'/></svg>");
  background-size: 140px 140px;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

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

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

:focus-visible {
  outline: 2px solid var(--ink);
  outline-offset: 3px;
}

h1,
h2,
h3 {
  font-family: 'Anton', 'Songti SC', 'SimSun', serif;
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: .004em;
  margin: 0 0 .5em;
}

h1 {
  font-size: clamp(2rem, 6.6vw, 4rem);
}

h2 {
  font-size: clamp(1.35rem, 3.4vw, 1.95rem);
}

h3 {
  font-size: 1.14rem;
}

p {
  margin: 0 0 1em;
}

ul,
ol {
  margin: 0 0 1em;
  padding-left: 1.25em;
}

.skip {
  position: absolute;
  top: -120px;
  left: 0;
  z-index: 95;
  background: var(--ink);
  color: var(--paper);
  padding: 12px 18px;
  min-height: 44px;
}

.skip:focus {
  top: 0;
}

/* ---------- 底部固定条 ---------- */
.dock {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 50;
  background: var(--paper);
  border-top: 2px solid var(--ink);
  padding: 6px 16px calc(8px + env(safe-area-inset-bottom));
}

.dock-brand {
  margin: 0;
  border-bottom: 1px solid var(--line);
}

.brand {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-family: 'Anton', 'Songti SC', serif;
  font-size: 1.15rem;
  letter-spacing: .02em;
}

.dock-bar {
  display: flex;
  align-items: center;
  gap: 10px;
  padding-top: 6px;
}

.burger,
.menu-close {
  min-height: 44px;
  padding: 0 16px;
  border: 1px solid var(--ink);
  border-radius: 0;
  background: var(--wash);
  color: var(--ink);
  font-family: inherit;
  font-size: .95rem;
  letter-spacing: .08em;
  cursor: pointer;
}

.burger:hover,
.menu-close:hover {
  background: var(--ink);
  color: var(--paper);
}

.dock-nav {
  flex: 1 1 auto;
  min-width: 0;
  display: none;
}

.dock-nav p {
  display: flex;
  flex-wrap: nowrap;
  gap: 2px;
  margin: 0;
  overflow-x: auto;
}

.dock-nav a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 12px;
  white-space: nowrap;
  font-size: .95rem;
  border-bottom: 2px solid transparent;
}

.dock-nav a:hover {
  text-decoration: none;
  border-bottom-color: var(--ink);
}

.dock-cta {
  margin-left: auto;
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 18px;
  background: var(--ink);
  color: var(--paper);
  letter-spacing: .08em;
  font-size: .95rem;
}

.dock-cta:hover {
  text-decoration: none;
  background: #000;
}

/* ---------- 全屏遮罩菜单 ---------- */
.menu {
  position: fixed;
  inset: 0;
  z-index: 70;
  display: flex;
  flex-direction: column;
  padding: 22px 20px 40px;
  background: var(--paper);
  overflow-y: auto;
  visibility: hidden;
  opacity: 0;
  transition: none;
}

.menu.open {
  visibility: visible;
  opacity: 1;
}

.menu-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  border-bottom: 2px solid var(--ink);
  padding-bottom: 12px;
}

.menu-title {
  font-family: 'Anton', 'Songti SC', serif;
  font-size: 1.3rem;
  letter-spacing: .1em;
}

.menu-nav {
  margin-top: 8px;
}

.menu-nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.menu-nav li {
  border-bottom: 1px solid var(--line);
}

.menu-nav a {
  display: flex;
  align-items: center;
  min-height: 60px;
  padding: 10px 4px;
  font-family: 'Anton', 'Songti SC', serif;
  font-size: 1.3rem;
}

/* ---------- 头图 ---------- */
.hero {
  position: relative;
  max-width: 1180px;
  margin: 0 auto;
  min-height: 45vh;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: clamp(12px, 3vw, 28px);
  padding: clamp(64px, 12vh, 108px) 20px clamp(26px, 6vh, 54px);
  border-bottom: 3px solid var(--ink);
}

.hero-text {
  margin-left: auto;
  max-width: 34ch;
  text-align: right;
}

.hero-text h1 {
  margin: 0;
  text-align: right;
}

.hero-icon {
  flex: 0 0 auto;
  width: clamp(38px, 9vw, 72px);
  height: auto;
  color: var(--ink);
}

.hero-badge {
  position: absolute;
  top: 14px;
  right: 20px;
  margin: 0;
}

.hero-badge a {
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  padding: 0 14px;
  border: 1px solid var(--ink);
  background: var(--wash);
  font-size: .82rem;
  letter-spacing: .18em;
}

.hero-badge a:hover {
  text-decoration: none;
  background: var(--ink);
  color: var(--paper);
}

/* ---------- 主体：左栏目录 + 正文 ---------- */
main {
  max-width: 1180px;
  margin: 0 auto;
  padding: 40px 20px 64px;
  display: grid;
  grid-template-columns: 232px minmax(0, 1fr);
  column-gap: 44px;
}

main > section.rail {
  grid-column: 1;
  grid-row: 1 / span 40;
  align-self: start;
}

.rail-box {
  position: sticky;
  top: 22px;
  border-top: 3px solid var(--ink);
  padding-top: 12px;
}

.rail-h {
  font-size: .95rem;
  letter-spacing: .2em;
  margin: 0;
}

.rail-box hr {
  margin: 10px 0 12px;
  border: 0;
  border-top: 1px solid var(--ink);
}

.rail-list {
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: .93rem;
  line-height: 1.5;
}

.rail-list li {
  border-bottom: 1px solid var(--line);
}

.rail-list a {
  display: flex;
  align-items: center;
  min-height: 42px;
  padding: 6px 2px;
}

.rail-list a:hover {
  text-decoration: none;
  background: var(--wash);
}

main > section:not(.rail) {
  grid-column: 2;
  padding: 4px 0 34px;
  margin-bottom: 10px;
  border-bottom: 1px solid var(--line);
  scroll-margin-top: 20px;
}

main > section:not(.rail):last-child {
  border-bottom: 0;
}

main > section:not(.rail) h2 + hr,
main > section:not(.rail) h3 + hr {
  border: 0;
  border-top: 2px solid var(--ink);
  width: 52px;
  margin: 12px 0 20px;
}

main > section:not(.rail) > p:first-of-type {
  font-size: 1.06rem;
}

main figure,
main > section aside {
  margin: 0 0 22px;
  padding: 16px 18px;
  background: var(--wash);
  border: 1px solid var(--line);
  border-bottom: 3px solid var(--ink);
  border-radius: 0;
}

main figure figcaption,
main > section aside p {
  font-size: .92rem;
  color: var(--mute);
  margin: 8px 0 0;
}

main > section aside p:first-child {
  margin-top: 0;
}

main blockquote {
  margin: 0 0 22px;
  padding: 4px 0 4px 18px;
  border-left: 4px solid var(--ink);
  font-size: 1.02rem;
}

main table {
  width: 100%;
  border-collapse: collapse;
  margin: 0 0 22px;
  font-size: .95rem;
}

main th,
main td {
  border-bottom: 1px solid var(--line);
  padding: 10px 8px;
  text-align: left;
}

main th {
  border-bottom: 2px solid var(--ink);
}

main code {
  background: var(--wash);
  padding: 1px 5px;
  font-size: .9em;
}

main img {
  border: 1px solid var(--line);
  border-bottom: 3px solid var(--ink);
  border-radius: 0;
}

/* ---------- 页脚 ---------- */
.site-foot {
  border-top: 3px solid var(--ink);
  padding-bottom: 48px;
}

.foot-cta a {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 34vh;
  padding: 32px 20px;
  font-family: 'Anton', 'Songti SC', serif;
  font-size: clamp(1.7rem, 6vw, 3rem);
  letter-spacing: .02em;
  border-bottom: 1px solid var(--line);
}

.foot-cta a:hover {
  text-decoration: none;
  background: var(--wash);
}

.foot-base {
  max-width: 1180px;
  margin: 0 auto;
  padding: 22px 20px 0;
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  justify-content: space-between;
  gap: 8px 28px;
}

.foot-addr {
  font-style: normal;
  font-size: .9rem;
  color: var(--mute);
  max-width: 46ch;
  line-height: 1.6;
}

.foot-brand {
  display: block;
  color: var(--ink);
  font-family: 'Anton', 'Songti SC', serif;
  font-size: 1rem;
  letter-spacing: .04em;
}

.foot-desc {
  display: block;
  margin-top: 4px;
}

.foot-links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0 18px;
  font-size: .9rem;
}

.foot-links a {
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  padding: 0 2px;
  border-bottom: 2px solid transparent;
}

.foot-links a:hover {
  text-decoration: none;
  border-bottom-color: var(--ink);
}

/* ---------- 滚动出现 ---------- */
.rv {
  opacity: 0;
  transform: translateY(8px);
  transition: opacity .3s linear, transform .3s ease-out;
}

.rv.in {
  opacity: 1;
  transform: none;
}

/* ---------- 断点 ---------- */
@media (min-width: 900px) {
  .dock-nav {
    display: block;
  }
  body {
    padding-bottom: 132px;
  }
}

@media (max-width: 860px) {
  main {
    grid-template-columns: 1fr;
    column-gap: 0;
    padding-top: 28px;
  }
  main > article.rail {
    grid-column: 1;
    grid-row: auto;
  }
  main > article:not(.rail) {
    grid-column: 1;
  }
  .rail-box {
    position: static;
    border-top: 0;
    border-bottom: 1px solid var(--line);
    padding-bottom: 12px;
    margin-bottom: 24px;
  }
  .rail-list {
    display: flex;
    flex-wrap: wrap;
    gap: 0 16px;
  }
  .rail-list li {
    border-bottom: 0;
  }
}

@media (max-width: 520px) {
  body {
    font-size: 16px;
    padding-bottom: 172px;
  }
  .hero {
    min-height: 45vh;
    padding-top: 62px;
  }
  .hero-text {
    max-width: 22ch;
  }
  .foot-base {
    flex-direction: column;
  }
  .foot-cta a {
    min-height: 26vh;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  .rv {
    opacity: 1;
    transform: none;
    transition: none;
  }
}

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