/* ============================================================
   1973棋牌 · 共享样式 /assets/site.css
   墨绿绒底座 + 奶油纸长读区 + 琥珀金单一主动作
   ============================================================ */

/* ---------- 1. 重置 ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

body {
  margin: 0;
  padding-top: var(--rail-h);
  background: var(--cream);
  color: var(--espresso);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

body.nav-open { overflow: hidden; }

h1, h2, h3, h4, h5, h6 { margin: 0; line-height: 1.2; font-weight: 700; }

p { margin: 0 0 1em; }
p:last-child { margin-bottom: 0; }

ul, ol { margin: 0; padding: 0; list-style: none; }

img, svg, video { max-width: 100%; display: block; }

a { color: inherit; }

button { font: inherit; color: inherit; }

table { border-collapse: collapse; width: 100%; }

:focus-visible {
  outline: 2px solid var(--amber-light);
  outline-offset: 3px;
  border-radius: 3px;
}

/* ---------- 2. 变量 ---------- */
:root {
  /* 色板 */
  --ink: #0E2B22;
  --ink-deep: #07170F;
  --felt: #153A2C;
  --cream: #F4EDE0;
  --amber: #D9A441;
  --amber-light: #F2D28A;
  --cinnabar: #CE3B2A;
  --celadon: #7FB3AC;
  --espresso: #221A14;
  --verdigris: #58756A;
  --celadon-deep: #3D6F68;
  --amber-deep: #8A6417;

  /* 尺度 */
  --rail-w: 240px;
  --rail-h: 64px;
  --content-max: 1180px;
  --gutter: clamp(18px, 4vw, 56px);
  --radius-sm: 4px;
  --radius: 8px;
  --radius-lg: 12px;
  --pill: 999px;

  /* 字体栈 */
  --serif: "Songti SC", "Source Han Serif SC", "Noto Serif SC", "SimSun", Georgia, "Times New Roman", serif;
  --sans: "PingFang SC", "Source Han Sans SC", "Noto Sans SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, "Courier New", monospace;

  /* 动效 */
  --ease: cubic-bezier(.22, .61, .36, 1);
  --dur: 240ms;
}

/* ---------- 3. 基础排版 ---------- */
.mono,
.index-num,
.rule-num { font-family: var(--mono); }

.mono { font-size: .92em; letter-spacing: .02em; }

.index-num {
  display: inline-block;
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--verdigris);
}

.rule-num {
  display: inline-block;
  min-width: 4.6em;
  font-size: 14px;
  letter-spacing: .04em;
  color: var(--espresso);
  font-variant-numeric: tabular-nums;
}

.eyebrow {
  margin: 0 0 10px;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--verdigris);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.rule-line {
  height: 1px;
  border: 0;
  margin: 26px 0;
  background: linear-gradient(90deg, rgba(88, 117, 106, .55), rgba(88, 117, 106, 0));
}

/* ---------- 4. 跳至主内容 ---------- */
.skip-link {
  position: fixed;
  left: 14px;
  top: -72px;
  z-index: 200;
  padding: 11px 20px;
  border-radius: var(--pill);
  background: var(--amber);
  color: var(--ink-deep);
  font-size: 14px;
  font-weight: 700;
  text-decoration: none;
  transition: top var(--dur) var(--ease);
}

.skip-link:focus { top: 14px; }

/* ---------- 5. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border: 1px solid transparent;
  border-radius: var(--pill);
  font-size: 15px;
  font-weight: 600;
  line-height: 1.3;
  text-decoration: none;
  cursor: pointer;
  transition: background-color var(--dur) var(--ease),
              color var(--dur) var(--ease),
              border-color var(--dur) var(--ease),
              transform var(--dur) var(--ease),
              box-shadow var(--dur) var(--ease);
}

.btn--amber {
  background: var(--amber);
  color: var(--ink-deep);
  box-shadow: 0 6px 18px rgba(217, 164, 65, .26);
}

.btn--amber:hover {
  background: var(--amber-light);
  transform: translateY(-2px);
}

.btn--ghost {
  background: transparent;
  border-color: rgba(244, 237, 224, .4);
  color: var(--cream);
}

.btn--ghost:hover {
  border-color: var(--amber);
  color: var(--amber);
}

.btn--block { display: flex; width: 100%; }

.btn--sm { padding: 9px 16px; font-size: 13px; }

/* ---------- 6. 头部 · 侧边轨道 ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 80;
}

.rail {
  position: relative;
  height: var(--rail-h);
  display: flex;
  align-items: center;
  padding: 0 14px;
  background-color: var(--ink);
  background-image:
    radial-gradient(circle at 18% 0%, rgba(217, 164, 65, .12), transparent 58%),
    linear-gradient(180deg, var(--felt) 0%, var(--ink) 52%, var(--ink-deep) 100%);
  border-bottom: 1px solid rgba(217, 164, 65, .26);
  color: var(--cream);
  box-shadow: 0 10px 26px rgba(7, 23, 15, .34);
}

.rail::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: .55;
  background-image: repeating-linear-gradient(45deg,
    rgba(127, 179, 172, .05) 0 1px,
    transparent 1px 6px);
}

.rail > * { position: relative; z-index: 1; }

.rail__top {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: 1 1 auto;
  min-width: 0;
}

/* 品牌 */
.brand {
  display: flex;
  align-items: center;
  gap: 11px;
  text-decoration: none;
  color: var(--cream);
  min-width: 0;
}

.brand__mark {
  flex: none;
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border-radius: 50%;
  border: 1px solid var(--amber);
  background: radial-gradient(circle, rgba(217, 164, 65, .2), transparent 72%);
  color: var(--amber);
  font-family: var(--serif);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .01em;
}

.brand__text { min-width: 0; }

.brand__name {
  display: block;
  font-family: var(--serif);
  font-size: 17px;
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: .01em;
}

.brand__sub {
  display: none;
  font-size: 10px;
  letter-spacing: .18em;
  color: var(--celadon);
  margin-top: 3px;
}

/* 版本徽章 */
.rail__badge {
  margin: 0;
  flex: 0 1 auto;
  min-width: 0;
  padding: 3px 9px;
  border: 1px solid rgba(127, 179, 172, .42);
  border-radius: var(--pill);
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: .06em;
  color: var(--celadon);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* 移动菜单按钮 */
.nav-toggle {
  margin-left: auto;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 13px;
  border: 1px solid rgba(127, 179, 172, .48);
  border-radius: var(--pill);
  background: transparent;
  color: var(--cream);
  font-size: 13px;
  letter-spacing: .08em;
  cursor: pointer;
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.nav-toggle:hover { border-color: var(--amber); color: var(--amber); }

.nav-toggle__bars {
  position: relative;
  display: block;
  width: 16px;
  height: 2px;
  background: currentColor;
  transition: background-color var(--dur) var(--ease);
}

.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 16px;
  height: 2px;
  background: currentColor;
  transition: transform var(--dur) var(--ease), top var(--dur) var(--ease);
}

.nav-toggle__bars::before { top: -5px; }
.nav-toggle__bars::after { top: 5px; }

.site-header[data-open] .nav-toggle__bars { background: transparent; }
.site-header[data-open] .nav-toggle__bars::before { top: 0; transform: rotate(45deg); }
.site-header[data-open] .nav-toggle__bars::after { top: 0; transform: rotate(-45deg); }

/* 移动端抽屉导航 */
.rail__nav {
  position: fixed;
  left: 0;
  right: 0;
  top: var(--rail-h);
  max-height: calc(100vh - var(--rail-h));
  overflow-y: auto;
  padding: 18px 18px 28px;
  background-color: var(--ink);
  background-image: linear-gradient(180deg, var(--ink) 0%, var(--ink-deep) 100%);
  border-bottom: 1px solid rgba(217, 164, 65, .3);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: opacity var(--dur) var(--ease),
              transform var(--dur) var(--ease),
              visibility var(--dur) var(--ease);
}

.site-header[data-open] .rail__nav {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.rail__legend {
  margin: 0 12px 6px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .2em;
  color: rgba(127, 179, 172, .8);
}

.nav-list {
  counter-reset: navidx;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.nav-link {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 11px 12px;
  border-left: 2px solid transparent;
  border-radius: var(--radius-sm);
  color: rgba(244, 237, 224, .84);
  font-size: 15px;
  text-decoration: none;
  transition: color var(--dur) var(--ease),
              background-color var(--dur) var(--ease),
              border-color var(--dur) var(--ease);
}

.nav-link::before {
  counter-increment: navidx;
  content: counter(navidx, decimal-leading-zero);
  flex: none;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .06em;
  color: var(--celadon);
}

.nav-link:hover {
  color: var(--amber-light);
  background: rgba(127, 179, 172, .1);
  border-left-color: rgba(217, 164, 65, .55);
}

.nav-link[aria-current="page"] {
  color: var(--ink-deep);
  background: var(--amber);
  border-left-color: var(--amber-light);
  font-weight: 700;
}

.nav-link[aria-current="page"]::before { color: rgba(7, 23, 15, .72); }

/* 轨道底部 */
.rail__foot {
  display: none;
  flex-direction: column;
  gap: 10px;
  margin-top: auto;
  padding-top: 18px;
}

.rail__progress {
  height: 3px;
  border-radius: var(--pill);
  background: rgba(127, 179, 172, .24);
  overflow: hidden;
}

.rail__progress-bar {
  display: block;
  width: 0;
  height: 100%;
  border-radius: var(--pill);
  background: linear-gradient(90deg, var(--celadon), var(--amber));
}

.rail__progress-caption {
  margin: 0;
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: .14em;
  color: rgba(127, 179, 172, .85);
}

/* ---------- 7. 页脚 ---------- */
.site-footer {
  position: relative;
  overflow: hidden;
  background-color: var(--ink);
  background-image:
    radial-gradient(circle at 84% 8%, rgba(217, 164, 65, .1), transparent 46%),
    linear-gradient(180deg, var(--ink) 0%, var(--ink-deep) 78%);
  color: rgba(244, 237, 224, .82);
}

.site-footer::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: .5;
  background-image: repeating-linear-gradient(45deg,
    rgba(127, 179, 172, .045) 0 1px,
    transparent 1px 7px);
}

.footer__inner,
.footer__contact,
.footer__legal { position: relative; z-index: 1; }

.footer__inner {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: clamp(40px, 6vw, 74px) var(--gutter) clamp(30px, 4vw, 46px);
  display: grid;
  gap: clamp(26px, 4vw, 52px);
}

.footer__title {
  margin: 0 0 12px;
  font-family: var(--serif);
  font-size: clamp(24px, 3vw, 32px);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -.01em;
  color: var(--cream);
}

.footer__note {
  margin: 0 0 20px;
  max-width: 42ch;
  font-size: 14px;
  line-height: 1.85;
  color: rgba(244, 237, 224, .68);
}

.footer__cols {
  display: grid;
  gap: 24px 28px;
}

.footer__col-title {
  margin: 0 0 12px;
  padding-bottom: 8px;
  border-bottom: 1px solid rgba(217, 164, 65, .32);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .12em;
  color: var(--amber-light);
}

.footer__links { display: flex; flex-direction: column; gap: 9px; }

.footer__links a {
  font-size: 14px;
  line-height: 1.6;
  color: rgba(244, 237, 224, .78);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.footer__links a:hover {
  color: var(--amber);
  border-bottom-color: rgba(217, 164, 65, .6);
}

.footer__contact {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 22px var(--gutter);
  border-top: 1px solid rgba(127, 179, 172, .22);
  display: flex;
  flex-wrap: wrap;
  gap: 10px 30px;
  font-size: 14px;
  color: rgba(244, 237, 224, .74);
}

.footer__contact-item { margin: 0; }

.footer__contact-item a {
  color: var(--celadon);
  text-decoration: none;
  border-bottom: 1px dashed rgba(127, 179, 172, .55);
}

.footer__contact-item a:hover { color: var(--amber-light); }

.footer__legal {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 16px var(--gutter) 32px;
  border-top: 1px solid rgba(127, 179, 172, .14);
  display: flex;
  flex-wrap: wrap;
  gap: 8px 24px;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: .04em;
  color: rgba(244, 237, 224, .52);
}

.footer__legal p { margin: 0; }

/* ---------- 8. 正文骨架 ---------- */
.page {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: clamp(30px, 5vw, 62px) var(--gutter) clamp(48px, 7vw, 96px);
}

.section { padding-block: clamp(26px, 4vw, 50px); }

.section__head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: 14px 24px;
  padding-bottom: 16px;
  margin-bottom: clamp(20px, 3vw, 32px);
  border-bottom: 1px solid rgba(88, 117, 106, .32);
}

.section__title {
  font-family: var(--serif);
  font-size: clamp(26px, 4vw, 42px);
  font-weight: 700;
  line-height: 1.08;
  letter-spacing: -.01em;
  color: var(--espresso);
}

.section__lead {
  margin: 12px 0 0;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.85;
  color: #4A4038;
}

/* 面包屑 */
.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0 0 22px;
  padding: 0;
  list-style: none;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--verdigris);
}

.breadcrumbs li { display: inline-flex; align-items: center; gap: 8px; }

.breadcrumbs li + li::before { content: "/"; color: var(--celadon); }

.breadcrumbs a {
  color: var(--verdigris);
  text-decoration: none;
  border-bottom: 1px solid rgba(88, 117, 106, .45);
}

.breadcrumbs a:hover { color: var(--espresso); border-bottom-color: var(--espresso); }

/* ---------- 9. 网格 ---------- */
.grid { display: grid; gap: clamp(16px, 2.4vw, 26px); }

.grid--asym,
.grid--split { grid-template-columns: minmax(0, 1fr); }

.grid--cards { grid-template-columns: repeat(auto-fill, minmax(238px, 1fr)); }

/* ---------- 10. 面板与标签 ---------- */
.panel {
  position: relative;
  padding: clamp(18px, 2.4vw, 28px);
  border: 1px solid rgba(88, 117, 106, .26);
  border-radius: var(--radius-lg);
  background: #FFFDF8;
}

.panel--felt {
  background-color: var(--felt);
  background-image: linear-gradient(160deg, var(--felt), var(--ink-deep));
  border-color: rgba(217, 164, 65, .3);
  color: var(--cream);
}

.panel--felt .section__title,
.panel--felt .panel__title { color: var(--cream); }

.panel--glass {
  background: rgba(244, 237, 224, .68);
  border-color: rgba(127, 179, 172, .42);
  backdrop-filter: blur(9px);
  -webkit-backdrop-filter: blur(9px);
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 11px;
  border: 1px solid currentColor;
  border-radius: var(--pill);
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: .08em;
  line-height: 1.5;
}

.tag--celadon { color: var(--celadon-deep); background: rgba(127, 179, 172, .16); }
.tag--amber { color: var(--amber-deep); background: rgba(217, 164, 65, .18); }
.tag--cinnabar { color: var(--cinnabar); background: rgba(206, 59, 42, .1); }

/* ---------- 11. 图片容器 ---------- */
.figure {
  position: relative;
  margin: 0;
  overflow: hidden;
  border-radius: var(--radius-lg);
  border: 1px solid rgba(127, 179, 172, .3);
  background-color: var(--ink);
  background-image: radial-gradient(circle at 50% 42%, var(--felt), var(--ink-deep));
}

.figure > img,
.figure__img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.figure--wide { aspect-ratio: 16 / 9; }
.figure--square { aspect-ratio: 1 / 1; }
.figure--portrait { aspect-ratio: 4 / 5; }
.figure--tall { aspect-ratio: 3 / 4; }

.figure__placeholder {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: .2em;
  color: rgba(244, 237, 224, .38);
}

.figure__placeholder::before {
  content: "";
  position: absolute;
  width: 58%;
  aspect-ratio: 1 / 1;
  border-radius: 50%;
  border: 1px solid rgba(127, 179, 172, .3);
  box-shadow:
    0 0 0 18px rgba(217, 164, 65, .07),
    0 0 0 38px rgba(127, 179, 172, .05);
}

.figure__cap {
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--verdigris);
}

/* ---------- 12. 标签页 ---------- */
.tabs { position: relative; }

.tabs__list {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  padding: 6px;
  border-radius: var(--pill);
  background: rgba(21, 58, 44, .09);
}

.tabs__tab {
  padding: 9px 18px;
  border: 0;
  border-radius: var(--pill);
  background: transparent;
  color: #3A4A44;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: background-color var(--dur) var(--ease),
              color var(--dur) var(--ease),
              transform var(--dur) var(--ease);
}

.tabs__tab:hover { color: var(--ink); transform: translateY(-1px); }

.tabs__tab[aria-selected="true"] {
  background: var(--ink);
  color: var(--amber-light);
}

.tabs__panel { padding-top: 22px; }

.tabs__panel[hidden] { display: none; }

/* ---------- 13. 显现动效 ---------- */
html.reveal-ready [data-reveal] {
  transition: opacity .55s var(--ease), transform .55s var(--ease);
}

html.reveal-ready [data-reveal]:not(.is-in) {
  opacity: 0;
  transform: translateY(16px);
}

/* ---------- 14. 断点 ---------- */
@media (min-width: 600px) {
  .brand__sub { display: block; }
  .footer__cols { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (min-width: 960px) {
  body { padding-top: 0; padding-left: var(--rail-w); }

  .site-header { right: auto; bottom: 0; width: var(--rail-w); }

  .rail {
    height: 100%;
    flex-direction: column;
    align-items: stretch;
    padding: 26px 20px 20px;
    border-bottom: 0;
    border-right: 1px solid rgba(217, 164, 65, .24);
    box-shadow: 10px 0 28px rgba(7, 23, 15, .26);
  }

  .rail__top {
    flex-direction: column;
    align-items: flex-start;
    gap: 16px;
    flex: none;
    padding-bottom: 18px;
    border-bottom: 1px solid rgba(127, 179, 172, .22);
  }

  .brand__mark { width: 46px; height: 46px; font-size: 13px; }
  .brand__name { font-size: 21px; }

  .rail__badge {
    padding: 6px 13px;
    font-size: 11px;
    letter-spacing: .08em;
    border-color: rgba(217, 164, 65, .38);
    color: var(--amber-light);
  }

  .nav-toggle { display: none; }

  .rail__nav {
    position: static;
    flex: 1 1 auto;
    max-height: none;
    overflow-y: auto;
    padding: 18px 0 0;
    background: transparent;
    border: 0;
    opacity: 1;
    visibility: visible;
    transform: none;
    transition: none;
  }

  .nav-link { padding: 12px 12px; font-size: 15px; }

  .rail__foot { display: flex; gap: 9px; border-top: 1px solid rgba(127, 179, 172, .22); }

  .footer__inner { grid-template-columns: minmax(0, 1fr) minmax(0, 2.3fr); }
  .footer__cols { grid-template-columns: repeat(4, minmax(0, 1fr)); }

  .grid--asym { grid-template-columns: minmax(0, 2fr) minmax(0, 1fr); }
  .grid--split { grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); }
}

@media (min-width: 1320px) {
  :root { --content-max: 1240px; }
}

/* ---------- 15. 降低动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
    scroll-behavior: auto !important;
  }

  html.reveal-ready [data-reveal]:not(.is-in) {
    opacity: 1;
    transform: none;
  }
}