/* ===========================================================
   海鸥体育赛场 · /assets/site.css
   reset / 变量 / 中文排版 / 头部 / 页脚 / 通用组件
   =========================================================== */

/* ---------- 1. Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body { margin: 0; }
h1, h2, h3, h4, h5, p, ul, ol, figure, blockquote, dl, dd { margin: 0; }
ul, ol { padding: 0; list-style: none; }
img, svg, video { max-width: 100%; display: block; }
button, input, select, textarea { font: inherit; color: inherit; }
button { background: none; border: 0; cursor: pointer; }
a { color: var(--tide-500); text-decoration: none; transition: color .2s ease; }
a:hover { color: var(--deep-700); }
:focus-visible { outline: 3px solid var(--neon); outline-offset: 3px; }

/* ---------- 2. 变量 ---------- */
:root {
  --deep-900: #061A2E;
  --deep-700: #0C3557;
  --tide-500: #1668B3;
  --foam: #F5FAFF;
  --paper: #F2EDE3;
  --gull: #8A9AA8;
  --ink: #0B1620;
  --neon: #17E0C8;
  --coral: #FF6A3D;
  --shallow: #CFE4F5;
  --max: 1240px;
  --gutter: 64px;
  --radius: 2px;
  --shadow-1: 0 1px 0 rgba(6, 26, 46, .04), 0 4px 10px rgba(6, 26, 46, .07);
  --shadow-2: 0 2px 0 rgba(6, 26, 46, .05), 0 6px 16px rgba(6, 26, 46, .10);
  --font-display: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --font-body: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --font-numeric: "Barlow Condensed", "Helvetica Neue", Arial, "PingFang SC", sans-serif;
  --header-h: 76px;
}

/* ---------- 3. 中文排版 ---------- */
body {
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.85;
  color: var(--ink);
  background: var(--foam);
  overflow-wrap: break-word;
}
h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 900;
  letter-spacing: -.02em;
  line-height: 1.05;
  color: var(--deep-900);
}
h1 { font-size: clamp(2rem, 5.4vw, 4.6rem); }
h2 { font-size: clamp(1.5rem, 3.2vw, 2.75rem); }
h3 { font-size: clamp(1.15rem, 1.8vw, 1.625rem); line-height: 1.25; font-weight: 800; }
h4 { font-size: 1.125rem; line-height: 1.35; font-weight: 800; }
p { max-width: 68ch; margin-bottom: 1.2em; }
p:last-child { margin-bottom: 0; }
.num, .stat__num, .tidal-band__date, .tidal-status__date, .footer-contact__value--num {
  font-family: var(--font-numeric);
  font-variant-numeric: tabular-nums;
  letter-spacing: .12em;
}
.section--deep h1, .section--deep h2, .section--deep h3, .poster-stack h1, .poster-stack h2, .poster-stack h3 { color: var(--foam); }

/* ---------- 4. 布局工具 ---------- */
.container { width: 100%; max-width: var(--max); margin-inline: auto; padding-inline: var(--gutter); }
.container--narrow { max-width: min(100%, 860px); }
.section { padding-block: clamp(48px, 7vw, 96px); }
.section--paper { background: var(--paper); }
.section--deep { background: var(--deep-900); color: var(--foam); }
.grid { display: grid; gap: 28px; }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.section-label {
  display: inline-flex; align-items: center; gap: 10px;
  font-size: .75rem; font-weight: 600; letter-spacing: .16em;
  color: var(--tide-500); margin-bottom: 14px;
}
.section-label::before { content: ""; width: 26px; height: 1px; background: currentColor; }
.section--deep .section-label { color: var(--neon); }
.slant--top { clip-path: polygon(0 3%, 100% 0, 100% 100%, 0 100%); }
.slant--bottom { clip-path: polygon(0 0, 100% 0, 100% 97%, 0 100%); }

/* ---------- 5. 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: .9375rem; font-weight: 600; letter-spacing: .04em;
  padding: 11px 20px; border: 1px solid transparent; border-radius: var(--radius);
  text-decoration: none; white-space: nowrap;
  transition: background-color .2s ease, color .2s ease, border-color .2s ease, transform .2s ease;
}
.btn--solid { background: var(--deep-900); color: var(--foam); }
.btn--solid:hover { background: var(--deep-700); color: var(--foam); }
.btn--ghost { border-color: var(--tide-500); color: var(--tide-500); background: transparent; }
.btn--ghost:hover { background: var(--tide-500); color: var(--foam); }
.btn--neon { background: var(--neon); color: var(--deep-900); }
.btn--neon:hover { background: #4deed9; color: var(--deep-900); }
.btn--coral { background: var(--coral); color: #fff; }
.btn--coral:hover { background: #ff855f; color: #fff; }

/* ---------- 6. 面包屑 ---------- */
.crumbs { border-bottom: 1px solid rgba(138, 154, 168, .3); }
.crumbs__list {
  display: flex; flex-wrap: wrap; gap: 8px;
  max-width: var(--max); margin-inline: auto;
  padding: 14px var(--gutter);
  font-size: .8125rem; letter-spacing: .04em; color: var(--gull);
}
.crumbs__item { display: flex; align-items: center; gap: 8px; }
.crumbs__item + .crumbs__item::before { content: "/"; color: var(--shallow); }
.crumbs__link { color: var(--gull); }
.crumbs__link:hover { color: var(--tide-500); }
.crumbs__link[aria-current="page"] { color: var(--deep-900); }

/* ---------- 7. 海报层 ---------- */
.poster-stack {
  position: relative; isolation: isolate; overflow: hidden;
  background: var(--deep-900); color: var(--foam);
  padding: clamp(56px, 9vw, 120px) 0;
}
.poster-stack__layer { position: absolute; pointer-events: none; }
.poster-stack__layer--base {
  inset: 0;
  background: radial-gradient(120% 90% at 84% -12%, rgba(23, 224, 200, .20), transparent 62%);
}
.poster-stack__layer--mid {
  left: -12%; right: -12%; bottom: -34%; height: 62%;
  background: var(--deep-700); opacity: .55; transform: rotate(-3deg);
  clip-path: polygon(0 42%, 100% 0, 100% 100%, 0 100%);
}
.poster-stack__layer--top {
  top: 0; right: 0; width: 40%; height: 100%;
  background: linear-gradient(180deg, rgba(22, 104, 179, .38), transparent 78%);
  clip-path: polygon(34% 0, 100% 0, 100% 100%, 0 100%);
}
.poster-stack__body { position: relative; z-index: 1; }
.poster-title {
  font-size: clamp(2.25rem, 7vw, 5.5rem);
  line-height: 1.02; letter-spacing: -.03em; margin-bottom: .35em;
}
.poster-stack .lead { font-size: clamp(1rem, 1.6vw, 1.125rem); color: var(--shallow); }

/* ---------- 8. 展览标签 ---------- */
.exhibit-label {
  display: flex; align-items: baseline; gap: 12px;
  padding-top: 12px; border-top: 1px solid rgba(138, 154, 168, .45);
  font-size: .8125rem; letter-spacing: .08em; color: var(--gull);
}
.exhibit-label__no {
  font-family: var(--font-numeric); font-variant-numeric: tabular-nums;
  letter-spacing: .16em; font-weight: 600; color: var(--tide-500);
}
.exhibit-label__text { color: var(--deep-900); }
.section--deep .exhibit-label, .poster-stack .exhibit-label { border-color: rgba(207, 228, 245, .28); color: var(--shallow); }
.section--deep .exhibit-label__no, .poster-stack .exhibit-label__no { color: var(--neon); }
.section--deep .exhibit-label__text, .poster-stack .exhibit-label__text { color: var(--foam); }

/* ---------- 9. 潮汐带 ---------- */
.tidal-band {
  display: grid; grid-auto-flow: column; grid-auto-columns: minmax(116px, 1fr);
  gap: 1px; background: var(--shallow); border: 1px solid var(--shallow);
  overflow-x: auto; scroll-snap-type: x mandatory;
  -webkit-overflow-scrolling: touch;
}
.tidal-band__col {
  scroll-snap-align: start; background: var(--foam);
  padding: 14px 14px 18px; min-height: 136px;
  display: flex; flex-direction: column; gap: 8px;
  transition: background-color .24s ease, transform .24s ease;
}
.tidal-band__col:hover { background: #fff; transform: translateY(-2px); }
.tidal-band__date { font-size: 1.125rem; font-weight: 600; color: var(--deep-900); }
.tidal-band__meta { font-size: .75rem; letter-spacing: .08em; color: var(--gull); }
.tidal-band__bar { margin-top: auto; height: 6px; background: var(--shallow); position: relative; overflow: hidden; }
.tidal-band__fill { position: absolute; inset: 0 auto 0 0; width: 68%; background: var(--tide-500); }
.tidal-band__status { display: inline-flex; align-items: center; gap: 6px; font-size: .75rem; color: var(--gull); }
.status-dot { width: 6px; height: 6px; border-radius: 50%; background: var(--neon); box-shadow: 0 0 0 3px rgba(23, 224, 200, .18); }
.tidal-band__col[data-state="today"] { background: var(--deep-900); }
.tidal-band__col[data-state="today"] .tidal-band__date { color: var(--neon); }
.tidal-band__col[data-state="today"] .tidal-band__meta,
.tidal-band__col[data-state="today"] .tidal-band__status { color: var(--shallow); }
.tidal-band__col[data-state="today"] .tidal-band__bar { background: rgba(207, 228, 245, .22); }
.tidal-band__col[data-state="today"] .tidal-band__fill { background: var(--neon); }

/* ---------- 10. 卡片 / 统计 / 图片容器 ---------- */
.card, .entry-card {
  background: #fff; border: 1px solid var(--shallow); border-radius: var(--radius);
  padding: 22px; box-shadow: var(--shadow-1);
  transition: transform .24s ease, border-color .24s ease, box-shadow .24s ease;
}
.card:hover, .entry-card:hover { transform: translateY(-4px); border-color: var(--tide-500); box-shadow: var(--shadow-2); }
.entry-card__label { font-size: .75rem; letter-spacing: .12em; color: var(--gull); margin-bottom: 10px; }
.entry-card__title { font-size: 1.125rem; font-weight: 800; color: var(--deep-900); margin-bottom: 8px; line-height: 1.35; }
.entry-card__meta { font-size: .8125rem; color: var(--gull); letter-spacing: .04em; }
.stat { display: flex; flex-direction: column; gap: 4px; padding-top: 12px; border-top: 1px solid rgba(138, 154, 168, .4); }
.stat__num { font-size: clamp(1.75rem, 3vw, 2.75rem); font-weight: 600; line-height: 1; color: var(--tide-500); }
.stat__label { font-size: .8125rem; letter-spacing: .08em; color: var(--gull); }
.section--deep .stat { border-color: rgba(207, 228, 245, .28); }
.section--deep .stat__num { color: var(--neon); }
.section--deep .stat__label { color: var(--shallow); }
.media-frame {
  position: relative; overflow: hidden; border: 1px solid var(--shallow); border-radius: var(--radius);
  aspect-ratio: 16 / 9;
  background: linear-gradient(140deg, var(--deep-700), var(--tide-500) 58%, var(--neon));
}
.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--tall { aspect-ratio: 4 / 5; }
.media-frame--square { aspect-ratio: 1 / 1; }
.media-frame__img, .media-frame img { width: 100%; height: 100%; object-fit: cover; display: block; }
.media-frame__caption {
  position: absolute; left: 0; right: 0; bottom: 0;
  padding: 10px 14px; font-size: .75rem; letter-spacing: .08em; color: var(--foam);
  background: linear-gradient(0deg, rgba(6, 26, 46, .82), transparent);
}

/* ---------- 11. 显现与滚动潮位 ---------- */
[data-reveal] { opacity: 1; }
.js-ready [data-reveal] { opacity: 0; transform: translateY(14px); transition: opacity .6s ease, transform .6s ease; }
.js-ready [data-reveal].is-visible { opacity: 1; transform: none; }
.tidal-progress {
  position: fixed; top: 0; right: 0; width: 3px; height: 100%;
  z-index: 70; pointer-events: none; background: rgba(6, 26, 46, .06);
}
.tidal-progress__bar {
  display: block; width: 100%; height: 0;
  background: linear-gradient(180deg, var(--deep-700), var(--tide-500) 45%, var(--neon));
}

/* ---------- 12. 头部 ---------- */
.skip-link {
  position: absolute; left: 12px; top: -70px; z-index: 100;
  background: var(--neon); color: var(--deep-900);
  padding: 10px 18px; font-weight: 700; letter-spacing: .04em;
  transition: top .2s ease;
}
.skip-link:focus { top: 12px; color: var(--deep-900); }
.site-header {
  position: sticky; top: 0; z-index: 60;
  background: var(--deep-900); color: var(--foam);
  border-bottom: 1px solid rgba(207, 228, 245, .14);
}
.site-header__inner {
  max-width: var(--max); margin-inline: auto;
  padding: 14px var(--gutter);
  min-height: var(--header-h);
  display: grid; grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center; gap: 20px 32px;
  transition: padding .28s ease, min-height .28s ease;
}
.brand { display: inline-flex; align-items: center; gap: 12px; color: var(--foam); }
.brand:hover { color: var(--foam); }
.brand__mark { width: 46px; height: 24px; flex: 0 0 auto; color: var(--neon); }
.brand__text { display: flex; flex-direction: column; line-height: 1.15; }
.brand__name { font-family: var(--font-display); font-weight: 900; font-size: 1.0625rem; letter-spacing: .06em; }
.brand__sub { font-size: .625rem; letter-spacing: .22em; color: var(--gull); }
.tidal-status { display: flex; align-items: center; gap: 14px; min-width: 0; }
.tidal-status__label {
  flex: 0 0 auto; font-size: .75rem; letter-spacing: .14em;
  color: var(--shallow); white-space: nowrap;
}
.tidal-status__bar {
  flex: 1 1 auto; min-width: 48px; height: 3px; position: relative; overflow: hidden;
  background: rgba(207, 228, 245, .2);
}
.tidal-status__fill {
  position: absolute; inset: 0 auto 0 0; width: 86%;
  background: linear-gradient(90deg, var(--tide-500), var(--neon));
}
.tidal-status__date { flex: 0 0 auto; font-size: .8125rem; color: var(--neon); }
.nav-cluster { display: flex; align-items: center; gap: 26px; justify-self: end; }
.site-nav { display: flex; align-items: center; gap: 26px; }
.site-nav__list { display: flex; align-items: center; gap: 26px; }
.site-nav__link {
  position: relative; display: inline-block;
  padding: 6px 2px; font-size: .9375rem; font-weight: 600; letter-spacing: .03em;
  color: rgba(245, 250, 255, .84);
  transition: color .2s ease;
}
.site-nav__link::after {
  content: ""; position: absolute; left: 0; right: 100%; bottom: 0; height: 2px;
  background: var(--neon); transition: right .24s ease;
}
.site-nav__link:hover { color: var(--foam); }
.site-nav__link:hover::after { right: 0; }
.site-nav__link[aria-current="page"] { color: var(--neon); }
.site-nav__link[aria-current="page"]::after { right: 0; background: var(--neon); }
.header-cta { display: none; }
.nav-toggle {
  display: none; align-items: center; gap: 10px;
  color: var(--foam); font-size: .8125rem; letter-spacing: .12em;
  border: 1px solid rgba(207, 228, 245, .32); border-radius: var(--radius);
  padding: 9px 12px;
}
.nav-toggle__bars { display: flex; flex-direction: column; gap: 4px; width: 18px; }
.nav-toggle__bars span { display: block; height: 2px; background: var(--neon); }
.nav-toggle[aria-expanded="true"] { border-color: var(--neon); color: var(--neon); }
.site-header.is-condensed .site-header__inner { padding-block: 9px; min-height: 56px; }
.site-header.is-condensed .tidal-status__label { display: none; }
.site-header.is-condensed .tidal-status__bar { height: 2px; }
.site-header.is-condensed .tidal-status__date { font-size: .75rem; }
.site-header.is-condensed .brand__sub { display: none; }
.site-header.is-condensed .header-cta { display: inline-flex; }

/* ---------- 13. 页脚 ---------- */
.site-footer {
  background: var(--paper); color: var(--ink);
  border-top: 1px solid rgba(138, 154, 168, .35);
}
.footer-grid {
  max-width: var(--max); margin-inline: auto;
  padding: clamp(40px, 5vw, 64px) var(--gutter) 36px;
  display: grid; grid-template-columns: 1.5fr 1fr 1fr 1.2fr; gap: 40px 32px;
}
.footer-brand__name {
  font-family: var(--font-display); font-weight: 900; font-size: 1.25rem;
  letter-spacing: .04em; color: var(--deep-900); margin-bottom: 12px;
}
.footer-brand__line { font-size: .9375rem; line-height: 1.75; color: var(--ink); max-width: 34ch; }
.footer-heading {
  font-size: .8125rem; font-weight: 600; letter-spacing: .16em;
  color: var(--deep-900); margin-bottom: 16px;
}
.footer-list { display: grid; gap: 10px; }
.footer-list__item { font-size: .9375rem; line-height: 1.55; color: var(--ink); }
.footer-list--plain .footer-list__item { font-size: .875rem; color: var(--gull); }
.footer-link { color: var(--ink); border-bottom: 1px solid transparent; }
.footer-link:hover { color: var(--tide-500); border-bottom-color: currentColor; }
.footer-contact { display: grid; gap: 12px; }
.footer-contact__row { display: grid; gap: 2px; }
.footer-contact__label { font-size: .75rem; letter-spacing: .12em; color: var(--gull); }
.footer-contact__value { font-size: .9375rem; line-height: 1.55; color: var(--ink); }
.footer-contact__value--num { letter-spacing: .08em; }
.footer-note { margin-top: 14px; font-size: .8125rem; line-height: 1.7; color: var(--gull); max-width: 38ch; }
.footer-bottom { border-top: 1px solid rgba(138, 154, 168, .35); }
.footer-bottom__inner {
  max-width: var(--max); margin-inline: auto;
  padding: 18px var(--gutter) 26px;
  display: flex; flex-wrap: wrap; gap: 10px 24px;
  align-items: center; justify-content: space-between;
  font-size: .8125rem; color: var(--gull);
}
.footer-legal { display: flex; align-items: center; gap: 10px; margin: 0; }
.footer-sep { color: var(--shallow); }
.footer-copy { margin: 0; letter-spacing: .04em; }

/* ---------- 14. 响应式 ---------- */
@media (max-width: 1120px) {
  :root { --gutter: 40px; }
  .tidal-status__label { display: none; }
  .footer-grid { grid-template-columns: 1.4fr 1fr 1fr; }
  .footer-grid .footer-col:last-child { grid-column: span 3; }
}
@media (max-width: 960px) {
  :root { --gutter: 20px; --header-h: 64px; }
  .site-header__inner { grid-template-columns: auto minmax(0, 1fr) auto; gap: 14px; }
  .nav-toggle { display: inline-flex; }
  .site-nav {
    position: absolute; left: 0; right: 0; top: 100%;
    display: block; padding: 12px var(--gutter) 26px;
    background: var(--deep-900);
    border-top: 1px solid rgba(207, 228, 245, .14);
    border-bottom: 1px solid rgba(207, 228, 245, .14);
    max-height: calc(100vh - var(--header-h) - 2px); overflow-y: auto;
    opacity: 0; visibility: hidden; transform: translateY(-10px);
    transition: opacity .24s ease, transform .24s ease, visibility .24s;
  }
  .site-nav[data-open="true"] { opacity: 1; visibility: visible; transform: none; }
  .site-nav__list { flex-direction: column; align-items: stretch; gap: 0; }
  .site-nav__list li { border-bottom: 1px solid rgba(207, 228, 245, .12); }
  .site-nav__link { display: block; padding: 14px 2px; font-size: 1.0625rem; }
  .site-nav__link::after { display: none; }
  .site-nav__link[aria-current="page"] { color: var(--neon); }
  .header-cta { display: inline-flex; margin-top: 18px; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px 24px; }
  .footer-grid .footer-col:last-child { grid-column: span 2; }
  .grid--3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 640px) {
  body { font-size: 16px; }
  .tidal-status { display: none; }
  .grid--2, .grid--3 { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .footer-grid .footer-col:last-child { grid-column: span 1; }
  .footer-bottom__inner { flex-direction: column; align-items: flex-start; }
  .tidal-progress { width: 2px; }
}

/* ---------- 15. 无障碍与动效偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }
  .js-ready [data-reveal] { opacity: 1; transform: none; }
  .card:hover, .entry-card:hover, .tidal-band__col:hover { transform: none; }
}