/* ============================================================
   四季体育赛场 · 共享样式表 /assets/site.css
   设计母题：赛场控制台 + 展签；纸张叠层、印刷边框、计时器刻度
   ============================================================ */

/* ---------- 01 设计变量 ---------- */
:root {
  --paper: #F8F6EF;
  --paper-2: #E7E2D4;
  --ink: #14181C;
  --muted: #5B6673;
  --green: #0B6B43;
  --green-deep: #06452B;
  --green-bright: #3AA870;
  --orange: #F26A0F;
  --orange-soft: #FFC08A;
  --night: #0A1A2F;
  --night-2: #1C3350;

  --line: rgba(20, 24, 28, 0.16);
  --line-strong: rgba(20, 24, 28, 0.36);
  --line-inverse: rgba(248, 246, 239, 0.22);
  --inverse-soft: rgba(248, 246, 239, 0.72);

  --font-sans: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: "Roboto Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;

  --fs-display: clamp(44px, 6.4vw, 92px);
  --fs-h2: clamp(26px, 3vw, 40px);
  --fs-h3: 20px;
  --fs-body: 17px;
  --fs-label: 12px;

  --shell: 1320px;
  --gutter: clamp(18px, 4vw, 44px);

  --header-top-h: 52px;
  --header-main-h: 64px;
  --header-h: calc(var(--header-top-h) + var(--header-main-h));

  --dur: 160ms;
  --ease: cubic-bezier(0.2, 0.8, 0.2, 1);
  --radius: 2px;
}

/* ---------- 02 Reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-padding-top: calc(var(--header-main-h) + 20px);
  scroll-behavior: smooth;
}

body {
  margin: 0;
  padding-top: var(--header-h);
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: var(--fs-body);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

h1, h2, h3, h4, p, figure, blockquote, dl, dd { margin: 0; }
ul, ol { margin: 0; padding: 0; list-style: none; }
img, svg, video { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; background: none; border: 0; padding: 0; cursor: pointer; }
table { border-collapse: collapse; width: 100%; }
strong { font-weight: 800; }

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

/* ---------- 03 中文排版 ---------- */
h1, h2, h3, h4 {
  font-weight: 800;
  line-height: 1.24;
  letter-spacing: -0.01em;
}

.display {
  font-size: var(--fs-display);
  font-weight: 900;
  line-height: 1.02;
  letter-spacing: -0.02em;
}

.h2 {
  font-size: var(--fs-h2);
  font-weight: 800;
  line-height: 1.25;
  letter-spacing: -0.01em;
}

.h3 {
  font-size: var(--fs-h3);
  font-weight: 700;
  line-height: 1.42;
}

.lead {
  font-size: clamp(17px, 1.4vw, 20px);
  line-height: 1.7;
  color: var(--muted);
  max-width: 40ch;
}

.kicker {
  font-family: var(--font-mono);
  font-size: var(--fs-label);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--green-deep);
}

.label {
  font-family: var(--font-mono);
  font-size: var(--fs-label);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--muted);
}

.text-mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.02em;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

/* ---------- 04 布局工具 ---------- */
.shell {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.stack > * + * { margin-top: clamp(16px, 2vw, 24px); }
.stack--tight > * + * { margin-top: 10px; }

.grid {
  display: grid;
  gap: clamp(20px, 3vw, 36px);
}
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--split { grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); }

.divider {
  height: 0;
  border: 0;
  border-top: 1.5px solid var(--line-strong);
  margin-block: clamp(32px, 5vw, 56px);
}

/* ---------- 05 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 44px;
  padding: 0 20px;
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.04em;
  border: 1.5px solid transparent;
  border-radius: var(--radius);
  white-space: nowrap;
  transition: background-color var(--dur) var(--ease),
              color var(--dur) var(--ease),
              border-color var(--dur) var(--ease),
              box-shadow var(--dur) var(--ease),
              transform var(--dur) var(--ease);
}

.btn--solid {
  background: var(--green);
  color: var(--paper);
  border-color: var(--green);
  box-shadow: 4px 4px 0 var(--orange);
}
.btn--solid:hover {
  background: var(--green-deep);
  border-color: var(--green-deep);
  transform: translate(-1px, -1px);
  box-shadow: 6px 6px 0 var(--orange);
}

.btn--ghost {
  background: transparent;
  color: var(--green-deep);
  border-color: var(--line-strong);
}
.btn--ghost:hover {
  background: var(--paper-2);
  border-color: var(--green);
  color: var(--green-deep);
}

.btn--orange {
  background: var(--orange);
  color: #1A0C02;
  border-color: var(--orange);
  box-shadow: 5px 5px 0 rgba(6, 69, 43, 0.9);
}
.btn--orange:hover {
  background: #FF7D22;
  transform: translate(-1px, -1px);
  box-shadow: 7px 7px 0 var(--green-deep);
}

/* ---------- 06 标签 / 展签 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--green-deep);
}
.tag::before {
  content: "";
  width: 18px;
  height: 1.5px;
  background: var(--orange);
  flex: 0 0 auto;
}
.tag--dark { color: var(--paper); }
.tag--dark::before { background: var(--orange-soft); }

/* ---------- 07 跳转链 ---------- */
.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 400;
  transform: translateY(-180%);
  padding: 10px 18px;
  background: var(--night);
  color: var(--paper);
  font-size: 14px;
  font-weight: 700;
  border: 1.5px solid var(--orange);
  border-radius: var(--radius);
  transition: transform var(--dur) var(--ease);
}
.skip-link:focus { transform: translateY(0); }

/* ---------- 08 头部：双层结构 ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 120;
  background: var(--paper);
}

/* 上层署名条 */
.header-top {
  overflow: hidden;
  max-height: var(--header-top-h);
  background: var(--green-deep);
  color: var(--paper);
  transition: max-height 0.24s var(--ease);
}
.site-header[data-condensed="true"] .header-top { max-height: 0; }

.header-top__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px 28px;
  min-height: var(--header-top-h);
}

.header-top__sign {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: rgba(248, 246, 239, 0.92);
  white-space: nowrap;
}
.header-top__sign::before {
  content: "";
  width: 8px;
  height: 8px;
  flex: 0 0 auto;
  background: var(--orange);
  box-shadow: 13px 0 0 rgba(248, 246, 239, 0.38);
}

.header-top__meta {
  display: flex;
  align-items: center;
  gap: 18px;
  flex-wrap: wrap;
}

.season-badge {
  display: inline-flex;
  align-items: center;
  padding: 3px 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--paper);
  background: rgba(248, 246, 239, 0.10);
  border: 1px solid var(--line-inverse);
  border-radius: var(--radius);
  white-space: nowrap;
}

.header-top__support {
  font-size: 12.5px;
  letter-spacing: 0.04em;
  color: rgba(248, 246, 239, 0.78);
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
  white-space: nowrap;
}
.header-top__support:hover {
  color: var(--orange-soft);
  border-bottom-color: var(--orange-soft);
}

/* 下层栏目条 */
.header-main {
  position: relative;
  background: var(--paper);
}
.header-main::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--green) 0 70%, var(--orange) 70% 100%);
}

.header-main__inner {
  display: flex;
  align-items: center;
  gap: clamp(14px, 2vw, 28px);
  min-height: var(--header-main-h);
  padding-block: 8px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
  color: var(--ink);
}
.brand__mark {
  position: relative;
  width: 22px;
  height: 22px;
  flex: 0 0 auto;
  background: var(--green);
  box-shadow: 4px 4px 0 var(--orange);
  transition: background-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}
.brand__mark::after {
  content: "";
  position: absolute;
  inset: 6px;
  background: var(--paper);
}
.brand__name {
  font-size: 17px;
  font-weight: 800;
  letter-spacing: -0.01em;
  white-space: nowrap;
}
.brand:hover .brand__mark {
  background: var(--green-deep);
  box-shadow: 4px 4px 0 var(--green-bright);
}

/* 移动端导航开关 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 9px 13px;
  border: 1.5px solid var(--line-strong);
  border-radius: var(--radius);
  background: var(--paper);
  color: var(--green-deep);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.12em;
  transition: background-color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.nav-toggle:hover { background: var(--paper-2); border-color: var(--green); }

.nav-toggle__lines {
  display: grid;
  gap: 4px;
  width: 18px;
}
.nav-toggle__lines span {
  display: block;
  height: 2px;
  background: var(--green-deep);
  transition: transform 0.18s var(--ease), opacity 0.12s linear;
}
.site-header[data-open="true"] .nav-toggle__lines span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.site-header[data-open="true"] .nav-toggle__lines span:nth-child(2) { opacity: 0; }
.site-header[data-open="true"] .nav-toggle__lines span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

.nav-toggle__text { white-space: nowrap; }

/* 主导航 */
.site-nav { margin-inline: auto; }

.site-nav__list {
  display: flex;
  align-items: center;
  gap: 2px;
}

.site-nav__link {
  position: relative;
  display: inline-flex;
  align-items: center;
  padding: 10px 14px;
  font-size: 15px;
  font-weight: 500;
  color: var(--ink);
  border-radius: var(--radius);
  transition: background-color var(--dur) var(--ease), color var(--dur) var(--ease);
}
.site-nav__link::after {
  content: "";
  position: absolute;
  left: 14px;
  right: 14px;
  bottom: 4px;
  height: 2px;
  background: var(--orange);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.18s var(--ease);
}
.site-nav__link:hover { background: var(--paper-2); }
.site-nav__link:hover::after { transform: scaleX(1); }
.site-nav__link[aria-current="page"] {
  color: var(--green);
  font-weight: 700;
}
.site-nav__link[aria-current="page"]::after { transform: scaleX(1); }

.header-actions {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
}
.header-actions .btn {
  min-height: 40px;
  padding-inline: 16px;
  font-size: 13.5px;
}

/* ---------- 09 页脚：看台式围合 ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(64px, 9vw, 120px);
  background: var(--green-deep);
  color: var(--paper);
  overflow: hidden;
}
.site-footer::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(circle at 88% -12%, rgba(58, 168, 112, 0.34), transparent 44%),
    radial-gradient(circle at 4% 108%, rgba(242, 106, 15, 0.20), transparent 38%),
    repeating-linear-gradient(90deg, rgba(248, 246, 239, 0.05) 0 1px, transparent 1px 96px);
}

.footer-top {
  position: relative;
  padding-block: clamp(48px, 7vw, 84px) clamp(36px, 5vw, 56px);
}

.footer-top__inner {
  display: grid;
  grid-template-columns: minmax(240px, 320px) minmax(0, 1fr);
  gap: clamp(32px, 5vw, 72px);
  align-items: start;
}

.footer-brand__name {
  font-size: clamp(22px, 2.4vw, 30px);
  font-weight: 900;
  letter-spacing: -0.01em;
  line-height: 1.2;
  padding-bottom: 12px;
  border-bottom: 1.5px solid var(--line-inverse);
}
.footer-brand__line {
  margin-top: 14px;
  font-size: 15px;
  line-height: 1.7;
  color: var(--inverse-soft);
  max-width: 26ch;
}
.footer-brand__cta { margin-top: 24px; }

.footer-cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(24px, 3.5vw, 48px);
}

.footer-col__title {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--orange-soft);
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line-inverse);
}

.footer-list {
  display: grid;
  gap: 10px;
  margin-top: 16px;
}

.footer-link {
  display: inline-block;
  font-size: 15px;
  color: rgba(248, 246, 239, 0.82);
  transition: color var(--dur) var(--ease), transform var(--dur) var(--ease);
}
.footer-link:hover {
  color: var(--paper);
  transform: translateX(4px);
}

.footer-contact {
  display: grid;
  gap: 12px;
  margin-top: 16px;
}
.footer-contact__row { display: grid; gap: 1px; }
.footer-contact__label {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: rgba(248, 246, 239, 0.48);
}
.footer-contact__value {
  font-size: 14.5px;
  line-height: 1.6;
  color: rgba(248, 246, 239, 0.9);
  word-break: break-word;
}
.footer-contact__value--mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.03em;
}

.footer-legal {
  position: relative;
  border-top: 1px solid var(--line-inverse);
}
.footer-legal__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 8px 24px;
  padding-block: 20px;
  font-size: 12.5px;
  color: rgba(248, 246, 239, 0.62);
}
.footer-legal__copy { letter-spacing: 0.02em; }
.footer-legal__icp {
  font-family: var(--font-mono);
  letter-spacing: 0.06em;
}
.site-footer :focus-visible { outline-color: var(--orange-soft); }

/* ---------- 10 面包屑 ---------- */
.breadcrumb {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
}
.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
}
.breadcrumb__item { display: inline-flex; align-items: center; gap: 8px; }
.breadcrumb__item + .breadcrumb__item::before {
  content: "/";
  color: var(--line-strong);
}
.breadcrumb__link {
  color: var(--green-deep);
  border-bottom: 1px solid transparent;
  transition: border-color var(--dur) var(--ease);
}
.breadcrumb__link:hover { border-bottom-color: var(--orange); }
.breadcrumb__current { color: var(--muted); }

/* ---------- 11 页面骨架 ---------- */
.page-main { display: block; }

.page-intro {
  padding-block: clamp(28px, 4vw, 52px) clamp(32px, 5vw, 64px);
  border-bottom: 1.5px solid var(--line-strong);
}
.page-intro__title {
  margin-top: 18px;
  font-size: clamp(30px, 4.2vw, 58px);
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: -0.02em;
}
.page-intro__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 20px;
  margin-top: 20px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

/* ---------- 12 章节头 ---------- */
.section-head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: clamp(16px, 2.6vw, 36px);
  align-items: start;
  padding-top: 18px;
  border-top: 1.5px solid var(--line-strong);
}
.section-num {
  font-family: var(--font-mono);
  font-size: clamp(48px, 5vw, 72px);
  font-weight: 700;
  line-height: 0.82;
  letter-spacing: -0.04em;
  color: var(--green-deep);
  font-variant-numeric: tabular-nums;
}
.section-head__body { min-width: 0; }
.section-head__title {
  font-size: var(--fs-h2);
  font-weight: 800;
  line-height: 1.24;
  letter-spacing: -0.01em;
}
.section-head__desc {
  margin-top: 16px;
  color: var(--muted);
  max-width: 58ch;
}

/* ---------- 13 卡片 ---------- */
.card {
  position: relative;
  background: var(--paper);
  border: 1.5px solid var(--ink);
  border-radius: var(--radius);
  padding: clamp(20px, 2.4vw, 32px);
  box-shadow: 6px 6px 0 rgba(20, 24, 28, 0.08);
}
.card--paper {
  border-color: var(--line-strong);
  box-shadow: 6px 6px 0 var(--paper-2);
}
.card--night {
  background: var(--night);
  color: var(--paper);
  border-color: var(--night);
  box-shadow: 6px 6px 0 rgba(242, 106, 15, 0.88);
}
.card--night .kicker,
.card--night .label { color: var(--orange-soft); }
.card--night .lead { color: rgba(248, 246, 239, 0.74); }

/* ---------- 14 图片容器（页面阶段放图） ---------- */
.media-frame {
  position: relative;
  overflow: hidden;
  margin: 0;
  background: var(--night);
  border: 1.5px solid var(--ink);
  border-radius: var(--radius);
  box-shadow: 8px 8px 0 var(--paper-2);
}
.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s var(--ease);
}
.media-frame:hover img { transform: scale(1.03); }

.media-frame--wide { aspect-ratio: 16 / 9; }
.media-frame--tall { aspect-ratio: 3 / 4; }
.media-frame--square { aspect-ratio: 1 / 1; }
.media-frame--band { aspect-ratio: 21 / 9; }

.media-frame__tag {
  position: absolute;
  left: 0;
  bottom: 0;
  padding: 6px 12px;
  background: var(--orange);
  color: #1A0C02;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.media-frame__cap {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 12px 16px;
  background: linear-gradient(180deg, transparent, rgba(10, 26, 47, 0.88));
  color: var(--paper);
  font-size: 13px;
  line-height: 1.5;
}

/* ---------- 15 进入动效协议 ---------- */
.js [data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.32s ease-out, transform 0.32s var(--ease);
}
.js [data-reveal].is-in {
  opacity: 1;
  transform: none;
}

/* ---------- 16 响应式 ---------- */
@media (max-width: 1180px) {
  .site-nav__link { padding: 10px 10px; font-size: 14.5px; }
  .site-nav__link::after { left: 10px; right: 10px; }
  .header-actions .btn--ghost { display: none; }
  .footer-cols { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 980px) {
  .nav-toggle {
    display: inline-flex;
    margin-inline-start: auto;
  }
  .header-actions { display: none; }

  .site-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    z-index: 6;
    margin: 0;
    background: var(--paper);
    border-bottom: 3px solid var(--green);
    box-shadow: 0 28px 48px rgba(10, 26, 47, 0.22);
    max-height: min(72vh, 560px);
    overflow-y: auto;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: opacity var(--dur) ease-out,
                transform 0.2s var(--ease),
                visibility 0.2s linear;
  }
  .site-header[data-open="true"] .site-nav {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding-block: 6px;
  }
  .site-nav__link {
    padding: 15px var(--gutter);
    font-size: 16px;
    border-bottom: 1px solid var(--line);
    border-radius: 0;
  }
  .site-nav__link::after { display: none; }
  .site-nav__link:hover { background: var(--paper-2); }
  .site-nav__link[aria-current="page"] {
    background: var(--paper-2);
    box-shadow: inset 4px 0 0 var(--orange);
  }

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

@media (max-width: 760px) {
  .header-top__sign { display: none; }
  .header-top__support { display: none; }
  .header-top__inner { justify-content: flex-start; }
  .grid--2,
  .grid--3,
  .grid--split { grid-template-columns: minmax(0, 1fr); }
  .section-head { grid-template-columns: minmax(0, 1fr); }
  .section-num { font-size: clamp(38px, 11vw, 56px); }
}

@media (max-width: 620px) {
  .footer-cols { grid-template-columns: minmax(0, 1fr); }
  .footer-legal__inner { flex-direction: column; align-items: flex-start; }
  .brand__name { font-size: 15.5px; }
  .brand__mark { width: 18px; height: 18px; box-shadow: 3px 3px 0 var(--orange); }
  .brand__mark::after { inset: 5px; }
}

/* ---------- 17 减弱动效 ---------- */
@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;
    transition-delay: 0ms !important;
  }
  .js [data-reveal] {
    opacity: 1 !important;
    transform: none !important;
  }
  .media-frame:hover img { transform: none; }
  .footer-link:hover { transform: none; }
}