/* =========================================================
   开元棋牌中心 · 共享样式 /assets/site.css
   深墨绿绒布 + 暗金刻度 · 非对称 · 工具型刊物气质
   ========================================================= */

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 132px;
}

body { margin: 0; }

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

button { font: inherit; color: inherit; background: none; border: 0; }

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

p { margin: 0; }

a { color: #E8B85C; text-decoration: none; }

/* ---------- 2. Tokens ---------- */
:root {
  --ink: #041512;
  --felt: #0A2723;
  --felt2: #10382F;
  --slate: #1E4A42;
  --gold: #C8A24A;
  --amber: #E8B85C;
  --pale: #F2F6F3;
  --sage: #8FA99B;
  --wine: #7A2E3B;
  --goldsoft: #F4E7C3;

  --shell: 1240px;
  --gut: clamp(18px, 4vw, 44px);
  --gap: clamp(16px, 2.6vw, 30px);
  --r-s: 6px;
  --r-m: 12px;
  --r-l: 22px;

  --line: rgba(200, 162, 74, 0.26);
  --line-soft: rgba(143, 169, 155, 0.20);
  --glass: rgba(16, 56, 47, 0.42);
  --shadow: 0 22px 48px -30px rgba(0, 0, 0, 0.85);

  --font-head: "Oswald", "Arial Narrow", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-body: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --font-mono: "JetBrains Mono", "Roboto Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

/* ---------- 3. Base ---------- */
body {
  min-height: 100vh;
  font-family: var(--font-body);
  font-size: clamp(15.5px, 1.05vw, 17px);
  line-height: 1.75;
  color: var(--pale);
  overflow-x: hidden;
  background-color: var(--felt);
  background-image:
    radial-gradient(1200px 640px at 82% -8%, rgba(200, 162, 74, 0.12), transparent 60%),
    radial-gradient(900px 760px at -10% 30%, rgba(30, 74, 66, 0.60), transparent 65%),
    linear-gradient(180deg, var(--felt) 0%, #08201D 55%, var(--felt) 100%);
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(143, 169, 155, 0.055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(143, 169, 155, 0.055) 1px, transparent 1px);
  background-size: 72px 72px;
  -webkit-mask-image: radial-gradient(120% 90% at 50% 0%, #000 0%, transparent 78%);
  mask-image: radial-gradient(120% 90% at 50% 0%, #000 0%, transparent 78%);
}

main { position: relative; z-index: 1; }

::selection { background: var(--gold); color: var(--ink); }

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

/* ---------- 4. Typography ---------- */
h1, h2, h3, h4 {
  font-family: var(--font-head);
  font-weight: 800;
  line-height: 1.14;
  margin: 0 0 0.5em;
  color: var(--pale);
  letter-spacing: 0.01em;
}

h1 { font-size: clamp(2.25rem, 5.6vw, 4.3rem); font-weight: 900; }
h2 { font-size: clamp(1.6rem, 3.4vw, 2.5rem); }
h3 { font-size: clamp(1.15rem, 2vw, 1.5rem); font-weight: 700; }
h4 { font-size: 1.05rem; font-weight: 700; letter-spacing: 0.04em; }

strong { font-weight: 700; }

code, .mono { font-family: var(--font-mono); letter-spacing: 0.02em; }

/* ---------- 5. Layout helpers ---------- */
.shell {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--gut);
}

.grid { display: grid; gap: var(--gap); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--asym { grid-template-columns: minmax(0, 1fr) minmax(0, 1.4fr); }

.divider {
  height: 1px;
  border: 0;
  margin: clamp(34px, 5vw, 76px) 0;
  background: linear-gradient(90deg, var(--line), rgba(143, 169, 155, 0.08) 60%, transparent);
}

/* ---------- 6. Common components ---------- */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--gold);
}

.eyebrow::before {
  content: "";
  width: 26px;
  height: 1px;
  background: var(--gold);
  opacity: 0.85;
}

.section-head {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 0.9fr);
  gap: clamp(14px, 3vw, 42px);
  align-items: end;
  margin-bottom: clamp(22px, 3.4vw, 40px);
  padding-bottom: clamp(14px, 2vw, 22px);
  border-bottom: 1px solid var(--line-soft);
}

.section-head__index {
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--sage);
}

.section-head__title { margin: 0; }

.section-head__lead {
  margin: 0;
  max-width: 52ch;
  color: var(--sage);
  font-size: 0.98rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 22px;
  border: 1px solid transparent;
  border-radius: 999px;
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 14.5px;
  letter-spacing: 0.06em;
  text-decoration: none;
  cursor: pointer;
  transition: transform 0.18s ease, background-color 0.18s ease, color 0.18s ease, border-color 0.18s ease;
}

.btn:hover { transform: translateY(-1px); }

.btn--gold {
  background-image: linear-gradient(140deg, var(--amber), var(--gold));
  color: var(--ink);
  box-shadow: 0 12px 26px -16px rgba(232, 184, 92, 0.9);
}

.btn--gold:hover { background-image: none; background-color: var(--goldsoft); }

.btn--ghost {
  background-color: rgba(16, 56, 47, 0.6);
  border-color: var(--line);
  color: var(--pale);
}

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

.btn--sm { padding: 8px 16px; font-size: 13px; }

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 11px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background-color: rgba(200, 162, 74, 0.10);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.1em;
  color: var(--gold);
}

.tag--wine {
  border-color: rgba(122, 46, 59, 0.6);
  background-color: rgba(122, 46, 59, 0.35);
  color: var(--goldsoft);
}

.card {
  position: relative;
  padding: clamp(18px, 2.4vw, 30px);
  border: 1px solid var(--line);
  border-radius: var(--r-m);
  background-image: linear-gradient(160deg, rgba(16, 56, 47, 0.92), rgba(10, 39, 35, 0.86));
  box-shadow: var(--shadow);
}

.card--glass {
  background-color: var(--glass);
  background-image: none;
  border-color: var(--line-soft);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
}

.card--gold {
  background-image: none;
  background-color: var(--goldsoft);
  border-color: transparent;
  color: var(--felt);
}

.card__num {
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.2em;
  color: var(--gold);
}

.card--gold .card__num { color: rgba(10, 39, 35, 0.62); }

.card__title {
  margin: 0 0 8px;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 1.15rem;
}

.card__text { margin: 0; color: var(--sage); }
.card--gold .card__text { color: rgba(10, 39, 35, 0.78); }

.crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--sage);
}

.crumbs a { color: var(--sage); border-bottom: 1px solid transparent; }
.crumbs a:hover { color: var(--amber); border-bottom-color: var(--amber); }
.crumbs span[aria-current="page"] { color: var(--pale); }
.crumbs li { display: inline-flex; align-items: center; gap: 8px; }
.crumbs li + li::before { content: "/"; color: rgba(143, 169, 155, 0.5); }

/* 响应式图片容器（页面阶段放入 <img> 或保留为占位） */
.media {
  position: relative;
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--r-m);
  background-color: var(--felt2);
  background-image:
    linear-gradient(150deg, rgba(200, 162, 74, 0.14), rgba(10, 39, 35, 0.9) 62%),
    repeating-linear-gradient(45deg, rgba(143, 169, 155, 0.09) 0 10px, transparent 10px 20px);
  isolation: isolate;
}

.media > img { width: 100%; height: 100%; object-fit: cover; }

.media--tall { aspect-ratio: 3 / 4; }
.media--square { aspect-ratio: 1 / 1; }
.media--wide { aspect-ratio: 21 / 9; }

.media__caption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.04em;
  color: var(--sage);
}

.media__chip {
  position: absolute;
  left: 14px;
  bottom: 14px;
  z-index: 2;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background-color: rgba(4, 21, 18, 0.72);
  -webkit-backdrop-filter: blur(6px);
  backdrop-filter: blur(6px);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.1em;
  color: var(--gold);
}

/* 视口显现 */
.reveal {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.55s ease, transform 0.55s ease;
}

.reveal.is-in { opacity: 1; transform: none; }

/* 章节锚点导航高亮（页面层 [data-toc]） */
[data-toc] a.is-active {
  color: var(--gold);
  border-color: var(--gold);
}

/* ---------- 7. Skip link & progress ---------- */
.skip-link {
  position: absolute;
  left: 12px;
  top: -70px;
  z-index: 90;
  padding: 10px 18px;
  border-radius: 0 0 var(--r-s) var(--r-s);
  background-color: var(--amber);
  color: var(--ink);
  font-weight: 700;
  text-decoration: none;
  transition: top 0.2s ease;
}

.skip-link:focus { top: 0; }

.progress {
  position: fixed;
  left: 0;
  right: 0;
  top: 0;
  height: 3px;
  z-index: 70;
  pointer-events: none;
  background-color: rgba(4, 21, 18, 0.55);
}

.progress__bar {
  display: block;
  height: 100%;
  width: 0;
  background-image: linear-gradient(90deg, var(--gold), var(--amber));
  transition: width 0.12s linear;
}

/* ---------- 8. Masthead ---------- */
.masthead {
  position: sticky;
  top: 0;
  z-index: 50;
  border-bottom: 1px solid var(--line);
  background-image: linear-gradient(180deg, rgba(10, 39, 35, 0.97), rgba(10, 39, 35, 0.88));
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
}

.masthead__inner {
  display: grid;
  grid-template-columns: minmax(200px, auto) 1fr;
  grid-template-areas:
    "lead meta"
    "nav nav";
  gap: 10px clamp(16px, 3vw, 40px);
  align-items: center;
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding: clamp(12px, 1.6vw, 18px) var(--gut) clamp(10px, 1.4vw, 14px);
}

.masthead__lead { grid-area: lead; min-width: 0; }

.brand {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  color: inherit;
  text-decoration: none;
}

.brand__mark {
  position: relative;
  flex: none;
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
}

.brand__mark i {
  position: absolute;
  width: 24px;
  height: 32px;
  border: 1.5px solid var(--gold);
  border-radius: 5px;
  background-image: linear-gradient(160deg, rgba(200, 162, 74, 0.22), rgba(10, 39, 35, 0.92));
}

.brand__mark i:nth-child(1) { transform: rotate(-15deg) translateX(-6px); opacity: 0.5; }
.brand__mark i:nth-child(2) { opacity: 0.78; }
.brand__mark i:nth-child(3) { transform: rotate(15deg) translateX(6px); border-color: var(--amber); }

.brand__text { display: grid; gap: 2px; min-width: 0; }

.brand__name {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(17px, 1.5vw, 21px);
  letter-spacing: 0.04em;
  color: var(--pale);
}

.brand__sub {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.14em;
  color: var(--sage);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.masthead__meta {
  grid-area: meta;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: flex-end;
  gap: 10px clamp(12px, 1.6vw, 22px);
  min-width: 0;
}

.masthead__page {
  display: grid;
  gap: 2px;
  margin: 0;
  line-height: 1.25;
}

.masthead__pagelabel {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.18em;
  color: var(--sage);
}

.masthead__page b {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 15px;
  color: var(--pale);
}

.masthead__status {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--sage);
  white-space: nowrap;
}

.statusdot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: var(--amber);
  box-shadow: 0 0 0 4px rgba(232, 184, 92, 0.16);
}

.masthead__cta { white-space: nowrap; }

.navtoggle {
  display: none;
  grid-area: toggle;
  align-items: center;
  gap: 10px;
  padding: 9px 16px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background-color: rgba(16, 56, 47, 0.72);
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--pale);
  cursor: pointer;
}

.navtoggle__box { display: inline-flex; flex-direction: column; gap: 4px; width: 16px; }

.navtoggle__box i {
  display: block;
  height: 1.5px;
  border-radius: 2px;
  background-color: var(--gold);
  transition: transform 0.22s ease, opacity 0.22s ease;
}

.navtoggle[aria-expanded="true"] .navtoggle__box i:nth-child(1) { transform: translateY(5.5px) rotate(45deg); }
.navtoggle[aria-expanded="true"] .navtoggle__box i:nth-child(2) { opacity: 0; }
.navtoggle[aria-expanded="true"] .navtoggle__box i:nth-child(3) { transform: translateY(-5.5px) rotate(-45deg); }

.mainnav {
  grid-area: nav;
  border-top: 1px solid var(--line-soft);
  padding-top: 8px;
}

.mainnav__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 2px clamp(12px, 2.6vw, 36px);
  counter-reset: navitem;
}

.mainnav__list a {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 2px;
  border-bottom: 2px solid transparent;
  color: var(--sage);
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 15px;
  letter-spacing: 0.08em;
  text-decoration: none;
  transition: color 0.2s ease, border-color 0.2s ease;
}

.mainnav__list a::before {
  counter-increment: navitem;
  content: "0" counter(navitem);
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.04em;
  color: var(--gold);
  opacity: 0.7;
}

.mainnav__list a:hover { color: var(--pale); }

.mainnav__list a[aria-current="page"] {
  color: var(--gold);
  border-bottom-color: var(--gold);
}

.mainnav__list a[aria-current="page"]::before { opacity: 1; color: var(--amber); }

/* ---------- 9. Footer ---------- */
.foot {
  position: relative;
  z-index: 1;
  margin-top: clamp(56px, 9vw, 120px);
  border-top: 1px solid var(--line);
  background-image: linear-gradient(180deg, rgba(16, 56, 47, 0.86), var(--ink) 72%);
  color: var(--sage);
}

.foot__inner {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding: clamp(34px, 5vw, 68px) var(--gut) 0;
}

.foot__grid {
  display: grid;
  grid-template-columns: 1.7fr 1fr 1fr 1.35fr;
  gap: clamp(22px, 3.6vw, 52px);
}

.foot__col--brand { padding-right: clamp(0px, 2vw, 26px); }

.foot__wordmark {
  margin: 0 0 12px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(1.3rem, 2.4vw, 1.75rem);
  letter-spacing: 0.03em;
  color: var(--pale);
}

.foot__note {
  margin: 0 0 16px;
  max-width: 40ch;
  font-size: 0.94rem;
  line-height: 1.8;
}

.foot__meta {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12.5px;
  color: var(--pale);
}

.foot__metakey {
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--gold);
}

.foot__title {
  margin: 0 0 14px;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 0.95rem;
  letter-spacing: 0.14em;
  color: var(--pale);
}

.foot__list { display: grid; gap: 9px; font-size: 0.94rem; }

.foot__list a {
  color: var(--sage);
  border-bottom: 1px solid transparent;
  padding-bottom: 1px;
  transition: color 0.18s ease, border-color 0.18s ease;
}

.foot__list a:hover { color: var(--amber); border-bottom-color: var(--amber); }

.foot__list--plain li {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 10px;
  line-height: 1.65;
  word-break: break-word;
}

.foot__key {
  padding-top: 4px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--gold);
}

.foot__cta {
  display: inline-flex;
  margin-top: 16px;
  padding-bottom: 3px;
  border-bottom: 1px solid var(--line);
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 0.9rem;
  letter-spacing: 0.08em;
  color: var(--gold);
}

.foot__cta:hover { color: var(--amber); border-bottom-color: var(--amber); }

.foot__base {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 26px;
  margin-top: clamp(30px, 4vw, 56px);
  padding: 20px 0 clamp(26px, 4vw, 36px);
  border-top: 1px solid var(--line-soft);
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--sage);
}

.foot__copy { margin: 0; color: var(--pale); }
.foot__fine { margin: 0; }

.totop {
  padding: 8px 16px;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.14em;
  color: var(--gold);
  cursor: pointer;
  opacity: 0.45;
  transition: opacity 0.2s ease, background-color 0.2s ease, border-color 0.2s ease;
}

.totop.is-on { opacity: 1; }
.totop:hover { background-color: rgba(200, 162, 74, 0.14); border-color: var(--amber); }

/* ---------- 10. Responsive ---------- */
@media (max-width: 1000px) {
  .foot__grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 960px) {
  .grid--3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grid--asym { grid-template-columns: minmax(0, 1fr); }
}

@media (max-width: 880px) {
  html { scroll-padding-top: 200px; }

  .masthead__inner {
    grid-template-columns: minmax(0, 1fr) auto;
    grid-template-areas:
      "lead toggle"
      "meta meta"
      "nav nav";
    gap: 10px 14px;
  }

  .navtoggle { display: inline-flex; }

  .masthead__meta {
    justify-content: space-between;
    gap: 10px 14px;
  }

  .masthead__page { display: none; }

  .mainnav {
    overflow: hidden;
    max-height: 0;
    opacity: 0;
    visibility: hidden;
    border-top: 0;
    padding-top: 0;
    transition: max-height 0.32s ease, opacity 0.26s ease, visibility 0.32s ease;
  }

  .mainnav[data-open] {
    max-height: 560px;
    opacity: 1;
    visibility: visible;
  }

  .mainnav__list { flex-direction: column; align-items: stretch; gap: 0; padding: 6px 0 12px; }

  .mainnav__list a {
    width: 100%;
    padding: 13px 2px;
    border-bottom: 1px solid var(--line-soft);
    font-size: 16px;
  }

  .mainnav__list a[aria-current="page"] { border-bottom-color: var(--gold); }

  .section-head { grid-template-columns: minmax(0, 1fr); align-items: start; }
}

@media (max-width: 720px) {
  .brand__sub { display: none; }
  .grid--2,
  .grid--3 { grid-template-columns: minmax(0, 1fr); }
  .foot__grid { grid-template-columns: minmax(0, 1fr); }
  .foot__base { justify-content: flex-start; }
}

@media (max-width: 460px) {
  .masthead__status { display: none; }
  .masthead__cta { flex: 1 1 auto; }
}

/* ---------- 11. Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }

  .reveal { opacity: 1 !important; transform: none !important; }
}