/* ==========================================================================
   components.css — 布局与组件
   目录
     01 顶栏导航
     02 品牌标识
     03 按钮
     04 Hero
     05 内页页头 + 子导航
     06 卡片
     07 图标徽章
     08 数字与统计
     09 三步流程
     10 双赛道
     11 时间轴
     12 数据素养能力枢纽图
     13 表格
     14 图片展示块
     15 引述 / 提示块
     16 二维码卡
     17 Logo 墙
     18 折叠面板
     19 行动号召（CTA）
     20 页脚
     21 回到顶部
   ========================================================================== */

/* ==========================================================================
   01 顶栏导航
   ========================================================================== */
.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: var(--z-header);
  height: var(--nav-h);
  display: flex;
  align-items: center;
  color: #fff;
  background: transparent;
  transition: background-color var(--dur) var(--ease-out),
    box-shadow var(--dur) var(--ease-out), height var(--dur) var(--ease-out);
}

/* 未滚动时压在深色 Hero 上，加一层自下而上的暗色渐变保证可读性 */
.site-header::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(6, 21, 48, 0.72), rgba(6, 21, 48, 0));
  opacity: 1;
  transition: opacity var(--dur) var(--ease-out);
  pointer-events: none;
}

.site-header.is-scrolled {
  height: 64px;
  background-color: rgba(10, 31, 68, 0.94);
  backdrop-filter: saturate(160%) blur(12px);
  -webkit-backdrop-filter: saturate(160%) blur(12px);
  box-shadow: 0 6px 24px rgba(6, 21, 48, 0.28);
}

.site-header.is-scrolled::before {
  opacity: 0;
}

.header__inner {
  position: relative;
  z-index: 1;
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

/* --- 导航主体 --- */
.nav {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav__list {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav__link {
  position: relative;
  display: block;
  padding: 10px 14px;
  font-size: var(--fs-sm);
  font-weight: var(--fw-medium);
  color: var(--c-on-dark-2);
  border-radius: var(--radius-sm);
  white-space: nowrap;
  transition: color var(--dur-fast) var(--ease-out),
    background-color var(--dur-fast) var(--ease-out);
}

.nav__link:hover {
  color: #fff;
  background-color: rgba(255, 255, 255, 0.08);
}

.nav__link::after {
  content: "";
  position: absolute;
  left: 14px;
  right: 14px;
  bottom: 2px;
  height: 2px;
  background: var(--c-gold-500);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--dur) var(--ease-out);
}

.nav__link.is-active {
  color: #fff;
}

.nav__link.is-active::after {
  transform: scaleX(1);
}

.nav__cta {
  margin-left: 10px;
}

/* --- 汉堡按钮 --- */
.nav-burger {
  display: none;
  width: 44px;
  height: 44px;
  flex: none;
  border-radius: var(--radius-sm);
  color: #fff;
  align-items: center;
  justify-content: center;
  transition: background-color var(--dur-fast) var(--ease-out);
}

.nav-burger:hover {
  background-color: rgba(255, 255, 255, 0.1);
}

.nav-burger__bars {
  position: relative;
  display: block;
  width: 22px;
  height: 2px;
  background: currentColor;
  border-radius: 2px;
  transition: background-color var(--dur-fast) var(--ease-out);
}

.nav-burger__bars::before,
.nav-burger__bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 22px;
  height: 2px;
  background: currentColor;
  border-radius: 2px;
  transition: transform var(--dur) var(--ease-out);
}

.nav-burger__bars::before { top: -7px; }
.nav-burger__bars::after { top: 7px; }

.nav-burger[aria-expanded="true"] .nav-burger__bars {
  background: transparent;
}

.nav-burger[aria-expanded="true"] .nav-burger__bars::before {
  transform: translateY(7px) rotate(45deg);
}

.nav-burger[aria-expanded="true"] .nav-burger__bars::after {
  transform: translateY(-7px) rotate(-45deg);
}

/* --- 移动端抽屉 --- */
.nav-drawer {
  position: fixed;
  inset: var(--nav-h-mobile) 0 0 0;
  z-index: var(--z-overlay);
  background: var(--c-navy-950);
  padding: 24px var(--gutter) 40px;
  overflow-y: auto;
  transform: translateY(-8px);
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--dur) var(--ease-out),
    transform var(--dur) var(--ease-out), visibility var(--dur);
}

.nav-drawer.is-open {
  opacity: 1;
  transform: none;
  visibility: visible;
}

.nav-drawer__list {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.nav-drawer__link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 4px;
  font-size: 1.0625rem;
  font-weight: var(--fw-medium);
  color: var(--c-on-dark-2);
  border-bottom: 1px solid var(--c-on-dark-line);
}

.nav-drawer__link.is-active {
  color: var(--c-gold-400);
}

.nav-drawer__foot {
  margin-top: 28px;
}

body.nav-open {
  overflow: hidden;
}

@media (max-width: 1080px) {
  .nav__list {
    display: none;
  }
  /* 移动端保留一个紧凑的报名入口，避免「报名」被收进汉堡菜单里 */
  .nav__cta {
    padding: 9px 16px;
    font-size: var(--fs-xs);
  }
  .nav-burger {
    display: inline-flex;
  }
  .site-header {
    height: var(--nav-h-mobile);
  }
  .site-header.is-scrolled {
    height: 56px;
  }
  .nav-drawer {
    inset: var(--nav-h-mobile) 0 0 0;
  }
}

@media (max-width: 430px) {
  .nav__cta {
    display: none;
  }
  .brand {
    gap: 9px;
  }
  .brand__logo {
    width: 34px;
    height: 34px;
    padding: 3px;
    border-radius: 9px;
  }
  .brand__name {
    font-size: 0.9375rem;
  }
}

/* 抽屉底部说明 */
.nav-drawer__note {
  margin-top: 14px;
  font-size: var(--fs-xs);
  color: var(--c-on-dark-3);
  text-align: center;
}

/* ==========================================================================
   02 品牌标识
   ========================================================================== */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: #fff;
  flex: none;
}

.brand:hover {
  color: #fff;
}

/* 品牌标志容器
   素材 docs/logo/白色.png 为「白底 + 深蓝标志」的不透明方图，
   因此用白色圆角底板承载；深色顶栏/页脚上仍能保持清晰可读。
   若后续拿到透明反白版，只需把 .brand__logo 的 background 去掉即可。 */
.brand__logo {
  display: block;
  flex: none;
  width: 40px;
  height: 40px;
  padding: 4px;
  background: #ffffff;
  border-radius: 10px;
  box-shadow: 0 2px 10px rgba(6, 21, 48, 0.3);
}

.brand__logo img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.brand__logo--footer {
  width: 46px;
  height: 46px;
  padding: 5px;
  border-radius: 12px;
}

.brand__text {
  display: flex;
  flex-direction: column;
  gap: 5px; /* 两行之间留出呼吸感，避免「赛事名 + 副标」挤在一起 */
  min-width: 0;
}

.brand__name {
  font-size: 1.0625rem;
  font-weight: var(--fw-black);
  letter-spacing: 0.02em;
  line-height: 1.12;
}

.brand__sub {
  font-family: var(--font-serif);
  font-size: 0.75rem;
  line-height: 1;
  letter-spacing: var(--ls-wide);
  color: var(--c-gold-400);
  text-transform: uppercase;
}

@media (max-width: 480px) {
  .brand__sub {
    display: none;
  }
}

/* ==========================================================================
   03 按钮
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 26px;
  font-size: var(--fs-sm);
  font-weight: var(--fw-bold);
  letter-spacing: 0.02em;
  line-height: 1;
  border-radius: var(--radius-pill);
  border: 1px solid transparent;
  cursor: pointer;
  white-space: nowrap;
  transition: transform var(--dur-fast) var(--ease-out),
    box-shadow var(--dur) var(--ease-out), background-color var(--dur-fast) var(--ease-out),
    color var(--dur-fast) var(--ease-out), border-color var(--dur-fast) var(--ease-out);
}

.btn:hover {
  transform: translateY(-2px);
}

.btn:active {
  transform: translateY(0);
}

/* 主按钮 · 金 */
.btn--primary {
  background: linear-gradient(135deg, var(--c-gold-400), var(--c-gold-600));
  color: var(--c-navy-950);
  box-shadow: var(--shadow-gold);
}

.btn--primary:hover {
  color: var(--c-navy-950);
  box-shadow: 0 12px 30px rgba(200, 162, 74, 0.42);
}

/* 次按钮 · 科技蓝 */
.btn--blue {
  background: var(--c-blue-600);
  color: #fff;
  box-shadow: 0 8px 22px rgba(30, 111, 186, 0.32);
}

.btn--blue:hover {
  background: var(--c-blue-700);
  color: #fff;
}

/* 幽灵按钮 · 深色底上 */
.btn--ghost {
  border-color: rgba(255, 255, 255, 0.42);
  color: #fff;
  background: rgba(255, 255, 255, 0.04);
}

.btn--ghost:hover {
  border-color: #fff;
  background: rgba(255, 255, 255, 0.12);
  color: #fff;
}

/* 描边按钮 · 浅色底上 */
.btn--outline {
  border-color: var(--c-line-strong);
  color: var(--c-navy-900);
  background: var(--c-surface);
}

.btn--outline:hover {
  border-color: var(--c-blue-600);
  color: var(--c-blue-700);
  box-shadow: var(--shadow-sm);
}

.btn--sm {
  padding: 10px 20px;
  font-size: var(--fs-xs);
}

.btn--lg {
  padding: 16px 34px;
  font-size: var(--fs-body);
}

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

.btn__arrow {
  transition: transform var(--dur) var(--ease-out);
}

.btn:hover .btn__arrow {
  transform: translateX(4px);
}

.btn-group {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

.btn-group--center {
  justify-content: center;
}

/* 文字链接 + 箭头 */
.link-arrow {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: var(--fs-sm);
  font-weight: var(--fw-bold);
  color: var(--c-blue-600);
}

.link-arrow::after {
  content: "→";
  transition: transform var(--dur) var(--ease-out);
}

.link-arrow:hover::after {
  transform: translateX(4px);
}

.section--navy .link-arrow,
.hero .link-arrow {
  color: var(--c-gold-400);
}

/* ==========================================================================
   04 Hero
   ========================================================================== */
.hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  padding-top: calc(var(--nav-h) + clamp(56px, 8vw, 110px));
  padding-bottom: clamp(64px, 8vw, 120px);
  background-color: var(--c-navy-950);
  background-image:
    radial-gradient(120% 90% at 12% 8%, rgba(30, 111, 186, 0.42), transparent 58%),
    radial-gradient(90% 80% at 88% 92%, rgba(200, 162, 74, 0.16), transparent 60%),
    linear-gradient(160deg, #061530 0%, #0a1f44 46%, #0e2a58 100%);
  color: #fff;
}

/* 网格纹理 */
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.05) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(120% 100% at 50% 0%, #000 20%, transparent 78%);
  -webkit-mask-image: radial-gradient(120% 100% at 50% 0%, #000 20%, transparent 78%);
  pointer-events: none;
}

/* 星海节点纹理 */
.hero__decor {
  position: absolute;
  inset: 0;
  z-index: -1;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.7;
  pointer-events: none;
}

.hero__inner {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1.08fr) minmax(0, 0.92fr);
  gap: clamp(32px, 5vw, 64px);
  align-items: center;
}

.hero__badge {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 7px 16px;
  margin-bottom: 24px;
  font-size: var(--fs-xs);
  font-weight: var(--fw-medium);
  letter-spacing: 0.06em;
  color: var(--c-gold-300);
  background: rgba(200, 162, 74, 0.12);
  border: 1px solid rgba(200, 162, 74, 0.4);
  border-radius: var(--radius-pill);
}

.hero__badge-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--c-gold-400);
  box-shadow: 0 0 0 4px rgba(200, 162, 74, 0.22);
  animation: pulse 2.4s var(--ease-in-out) infinite;
}

@keyframes pulse {
  0%, 100% { box-shadow: 0 0 0 4px rgba(200, 162, 74, 0.22); }
  50% { box-shadow: 0 0 0 9px rgba(200, 162, 74, 0); }
}

.hero__title {
  font-size: var(--fs-display);
  font-weight: var(--fw-black);
  line-height: 1.12;
  letter-spacing: -0.02em;
  color: #fff;
  margin-bottom: 22px;
}

.hero__title-en {
  display: block;
  font-family: var(--font-serif);
  font-size: 0.34em;
  font-weight: var(--fw-bold);
  letter-spacing: 0.14em;
  color: var(--c-gold-400);
  text-transform: uppercase;
  margin-bottom: 14px;
}

.hero__title em {
  font-style: normal;
  background: linear-gradient(100deg, #ffffff 0%, #a9cdec 48%, #d9b865 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero__lead {
  font-size: var(--fs-lead);
  color: var(--c-on-dark-2);
  max-width: 34em;
  margin-bottom: 34px;
}

/* 居中版式（404 等） */
.text-center .hero__lead {
  margin-inline: auto;
}

.hero__actions {
  margin-bottom: 40px;
}

.hero__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 28px;
  padding-top: 26px;
  border-top: 1px solid var(--c-on-dark-line);
}

.hero__meta-item {
  display: flex;
  align-items: baseline;
  gap: 8px;
  font-size: var(--fs-sm);
  color: var(--c-on-dark-2);
}

.hero__meta-item .num {
  font-family: var(--font-serif);
  font-size: 1.5rem;
  font-weight: var(--fw-bold);
  color: var(--c-gold-400);
  line-height: 1;
}

/* Hero 右侧：赛事速览卡 */
.hero__panel {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--c-on-dark-line);
  border-radius: var(--radius-lg);
  padding: clamp(20px, 3vw, 32px);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  box-shadow: 0 24px 64px rgba(0, 0, 0, 0.32);
}

.hero__panel-title {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: var(--fs-h4);
  font-weight: var(--fw-bold);
  color: #fff;
  padding-bottom: 16px;
  margin-bottom: 6px;
  border-bottom: 1px solid var(--c-on-dark-line);
}

.hero__panel-title::before {
  content: "";
  width: 4px;
  height: 18px;
  border-radius: 2px;
  background: var(--c-gold-500);
}

.info-row {
  display: grid;
  grid-template-columns: 84px minmax(0, 1fr);
  gap: 16px;
  padding: 14px 0;
  border-bottom: 1px dashed rgba(255, 255, 255, 0.12);
}

.info-row:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.info-row__label {
  font-size: var(--fs-xs);
  color: var(--c-on-dark-3);
  padding-top: 2px;
}

.info-row__value {
  font-size: var(--fs-sm);
  font-weight: var(--fw-medium);
  color: #fff;
}

.info-row__value .sub {
  display: block;
  font-size: var(--fs-xs);
  font-weight: var(--fw-regular);
  color: var(--c-on-dark-3);
  margin-top: 4px;
}

@media (max-width: 980px) {
  .hero__inner {
    grid-template-columns: minmax(0, 1fr);
  }
  .hero__panel {
    order: 2;
  }
}

/* ==========================================================================
   05 内页页头 + 子导航
   ========================================================================== */
.page-hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  padding-top: calc(var(--nav-h) + clamp(48px, 6vw, 84px));
  padding-bottom: clamp(40px, 5vw, 72px);
  background-color: var(--c-navy-950);
  background-image:
    radial-gradient(110% 120% at 8% 0%, rgba(30, 111, 186, 0.40), transparent 60%),
    linear-gradient(150deg, #061530 0%, #0a1f44 55%, #123163 100%);
  color: #fff;
}

.page-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.045) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: linear-gradient(180deg, #000, transparent 92%);
  -webkit-mask-image: linear-gradient(180deg, #000, transparent 92%);
  pointer-events: none;
}

.page-hero__index {
  display: inline-block;
  font-family: var(--font-serif);
  font-size: 0.8125rem;
  font-weight: var(--fw-bold);
  letter-spacing: var(--ls-wider);
  color: var(--c-gold-400);
  margin-bottom: 12px;
}

.page-hero__title {
  font-size: var(--fs-h1);
  color: #fff;
  margin-bottom: 18px;
}

.page-hero__lead {
  max-width: 46em;
  font-size: var(--fs-lead);
  color: var(--c-on-dark-2);
}

.page-hero__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 12px;
  margin-top: 28px;
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  font-size: var(--fs-xs);
  font-weight: var(--fw-medium);
  color: var(--c-on-dark-2);
  background: rgba(255, 255, 255, 0.07);
  border: 1px solid var(--c-on-dark-line);
  border-radius: var(--radius-pill);
}

/* 子导航：吸顶锚点 */
.subnav {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--c-line);
}

.subnav__inner {
  display: flex;
  align-items: center;
  gap: 4px;
  overflow-x: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
}

.subnav__inner::-webkit-scrollbar {
  display: none;
}

.subnav__link {
  position: relative;
  display: block;
  padding: 16px 14px;
  font-size: var(--fs-sm);
  font-weight: var(--fw-medium);
  color: var(--c-ink-2);
  white-space: nowrap;
}

.subnav__link:hover {
  color: var(--c-blue-600);
}

.subnav__link.is-active {
  color: var(--c-navy-900);
  font-weight: var(--fw-bold);
}

.subnav__link.is-active::after {
  content: "";
  position: absolute;
  left: 14px;
  right: 14px;
  bottom: 0;
  height: 2px;
  background: var(--c-gold-500);
}

/* ==========================================================================
   06 卡片
   ========================================================================== */
.card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: clamp(20px, 2.6vw, 30px);
  background: var(--c-surface);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-xs);
  transition: transform var(--dur) var(--ease-out),
    box-shadow var(--dur) var(--ease-out), border-color var(--dur) var(--ease-out);
}

.card--hoverable:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
  border-color: var(--c-blue-200);
}

.card--flush {
  padding: 0;
  overflow: hidden;
}

.card__index {
  font-family: var(--font-serif);
  font-size: 0.8125rem;
  font-weight: var(--fw-bold);
  letter-spacing: var(--ls-wide);
  color: var(--c-blue-600);
}

.card__title {
  font-size: var(--fs-h4);
  font-weight: var(--fw-bold);
  color: var(--c-navy-900);
}

.card__text {
  font-size: var(--fs-sm);
  color: var(--c-ink-2);
  line-height: 1.85;
}

.card__foot {
  margin-top: auto;
  padding-top: 6px;
}

/* 顶部金线强调卡 */
.card--accent::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  border-radius: var(--radius) var(--radius) 0 0;
  background: linear-gradient(90deg, var(--c-blue-600), var(--c-gold-500));
  opacity: 0;
  transition: opacity var(--dur) var(--ease-out);
}

.card--accent:hover::before {
  opacity: 1;
}

/* 深色卡片 */
.card--navy {
  background: linear-gradient(150deg, var(--c-navy-900), var(--c-navy-800));
  border-color: rgba(255, 255, 255, 0.12);
  color: #fff;
}

.card--navy .card__title {
  color: #fff;
}

.card--navy .card__text {
  color: var(--c-on-dark-2);
}

.card--navy .card__index {
  color: var(--c-gold-400);
}

/* 列表卡：带左侧编号 */
.card-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

/* ==========================================================================
   07 图标徽章
   ========================================================================== */
.icon-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 46px;
  height: 46px;
  flex: none;
  border-radius: 12px;
  background: var(--c-blue-50);
  color: var(--c-blue-600);
  border: 1px solid var(--c-blue-100);
}

.icon-badge svg {
  width: 23px;
  height: 23px;
}

.icon-badge--gold {
  background: var(--c-gold-50);
  color: var(--c-gold-600);
  border-color: var(--c-gold-300);
}

.icon-badge--navy {
  background: rgba(255, 255, 255, 0.08);
  color: var(--c-gold-400);
  border-color: rgba(255, 255, 255, 0.16);
}

.icon-badge--lg {
  width: 58px;
  height: 58px;
  border-radius: 16px;
}

.icon-badge--lg svg {
  width: 28px;
  height: 28px;
}

/* ==========================================================================
   08 数字与统计
   ========================================================================== */
.stat-strip {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  background: var(--c-line);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  overflow: hidden;
}

.stat {
  padding: clamp(20px, 3vw, 32px);
  background: var(--c-surface);
  text-align: center;
}

.stat__value {
  font-family: var(--font-serif);
  font-size: clamp(1.75rem, 3.4vw, 2.5rem);
  font-weight: var(--fw-bold);
  line-height: 1;
  color: var(--c-navy-900);
  margin-bottom: 10px;
}

.stat__value .unit {
  font-family: var(--font-sans);
  font-size: 0.42em;
  font-weight: var(--fw-bold);
  color: var(--c-blue-600);
  margin-left: 4px;
}

.stat__label {
  font-size: var(--fs-xs);
  color: var(--c-ink-3);
}

@media (max-width: 860px) {
  .stat-strip {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

/* ==========================================================================
   09 三步流程
   ========================================================================== */
.steps {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(20px, 3vw, 32px);
  position: relative;
}

.step {
  position: relative;
  padding: clamp(24px, 3vw, 34px) clamp(20px, 2.6vw, 30px);
  background: var(--c-surface);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-xs);
  transition: transform var(--dur) var(--ease-out), box-shadow var(--dur) var(--ease-out);
}

.step:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-md);
}

.step__no {
  font-family: var(--font-serif);
  font-size: 2.25rem;
  font-weight: var(--fw-bold);
  line-height: 1;
  color: var(--c-blue-200);
  margin-bottom: 16px;
}

.step__title {
  font-size: var(--fs-h4);
  margin-bottom: 10px;
}

.step__text {
  font-size: var(--fs-sm);
  color: var(--c-ink-2);
}

/* 连接箭头 */
.step__arrow {
  position: absolute;
  top: 50%;
  right: -22px;
  transform: translateY(-50%);
  width: 14px;
  height: 14px;
  border-top: 2px solid var(--c-blue-200);
  border-right: 2px solid var(--c-blue-200);
  rotate: 45deg;
  z-index: 2;
}

.step:last-child .step__arrow {
  display: none;
}

@media (max-width: 860px) {
  .steps {
    grid-template-columns: minmax(0, 1fr);
  }
  .step__arrow {
    top: auto;
    bottom: -22px;
    right: 50%;
    transform: translateX(50%);
    rotate: 135deg;
  }
}

/* 纵向流程（关于大赛页） */
.flow {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 18px;
  padding-left: 8px;
}

.flow::before {
  content: "";
  position: absolute;
  left: 27px;
  top: 12px;
  bottom: 12px;
  width: 2px;
  background: linear-gradient(180deg, var(--c-blue-200), var(--c-gold-300));
}

.flow__item {
  position: relative;
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  gap: 20px;
  align-items: start;
  padding: 20px 24px 20px 0;
}

.flow__node {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--c-navy-900);
  color: var(--c-gold-400);
  font-family: var(--font-serif);
  font-size: var(--fs-sm);
  font-weight: var(--fw-bold);
  box-shadow: 0 0 0 5px var(--c-surface);
}

.section--tint .flow__node {
  box-shadow: 0 0 0 5px var(--c-surface-2);
}

.section--blue .flow__node {
  box-shadow: 0 0 0 5px var(--c-blue-50);
}

.flow__title {
  font-size: var(--fs-h4);
  margin-bottom: 6px;
}

.flow__text {
  font-size: var(--fs-sm);
  color: var(--c-ink-2);
}

/* ==========================================================================
   10 双赛道
   ========================================================================== */
.tracks {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(20px, 3vw, 32px);
}

.track {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: clamp(26px, 3.4vw, 42px);
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--c-line);
  background: var(--c-surface);
  box-shadow: var(--shadow-sm);
  transition: transform var(--dur) var(--ease-out), box-shadow var(--dur) var(--ease-out);
}

.track:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
}

.track::after {
  content: "";
  position: absolute;
  right: -60px;
  top: -60px;
  width: 200px;
  height: 200px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(30, 111, 186, 0.14), transparent 70%);
  pointer-events: none;
}

.track--team::after {
  background: radial-gradient(circle, rgba(200, 162, 74, 0.18), transparent 70%);
}

.track__head {
  display: flex;
  align-items: center;
  gap: 14px;
}

.track__title {
  font-size: var(--fs-h3);
}

.track__title small {
  display: block;
  font-size: 0.8125rem;
  font-weight: var(--fw-medium);
  color: var(--c-blue-600);
  letter-spacing: 0.04em;
  margin-top: 4px;
}

.track--team .track__title small {
  color: var(--c-gold-600);
}

.track__list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-top: 4px;
}

.track__list li {
  position: relative;
  padding-left: 20px;
  font-size: var(--fs-sm);
  color: var(--c-ink-2);
}

.track__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.62em;
  width: 7px;
  height: 7px;
  border-radius: 2px;
  background: var(--c-blue-400);
  rotate: 45deg;
}

.track--team .track__list li::before {
  background: var(--c-gold-500);
}

.track__foot {
  margin-top: auto;
  padding-top: 8px;
}

@media (max-width: 860px) {
  .tracks {
    grid-template-columns: minmax(0, 1fr);
  }
}

/* ==========================================================================
   11 时间轴
   ========================================================================== */
.timeline {
  position: relative;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(20px, 3vw, 32px);
}

.timeline::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 48px;
  height: 2px;
  background: linear-gradient(
    90deg,
    transparent,
    var(--c-blue-200) 8%,
    var(--c-blue-200) 92%,
    transparent
  );
  z-index: 0;
}

.timeline__item {
  position: relative;
  z-index: 1;
}

.timeline__date {
  display: block;
  height: 36px;
  font-family: var(--font-serif);
  font-size: 1.375rem;
  font-weight: var(--fw-bold);
  line-height: 36px;
  color: var(--c-navy-900);
  margin-bottom: 4px;
}

.timeline__node {
  display: block;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--c-surface);
  border: 3px solid var(--c-blue-600);
  box-shadow: 0 0 0 5px var(--c-blue-50);
  margin-bottom: 22px;
}

.timeline__item:last-child .timeline__node {
  border-color: var(--c-gold-500);
  box-shadow: 0 0 0 5px var(--c-gold-50);
}

.timeline__title {
  font-size: var(--fs-h4);
  margin-bottom: 8px;
}

.timeline__desc {
  font-size: var(--fs-sm);
  color: var(--c-ink-2);
}

.section--navy .timeline__date {
  color: #fff;
}

.section--navy .timeline::before {
  background: linear-gradient(
    90deg,
    transparent,
    var(--c-on-dark-line) 8%,
    var(--c-on-dark-line) 92%,
    transparent
  );
}

.section--navy .timeline__node {
  background: var(--c-navy-900);
  border-color: var(--c-gold-400);
  box-shadow: 0 0 0 5px rgba(200, 162, 74, 0.16);
}

.section--navy .timeline__desc {
  color: var(--c-on-dark-2);
}

/* 两节点时间轴（紧凑） */
.timeline--2 {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

/* 五节点时间轴（团队赛全流程实战链路） */
.timeline--5 {
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: clamp(16px, 2vw, 24px);
}

.timeline--5 .timeline__date {
  font-size: 1.125rem;
}

.timeline--5 .timeline__title {
  font-size: var(--fs-h4);
}

@media (max-width: 1080px) {
  .timeline,
  .timeline--2,
  .timeline--5 {
    grid-template-columns: minmax(0, 1fr);
    gap: 0;
  }
  .timeline::before {
    left: 8px;
    right: auto;
    top: 10px;
    bottom: 10px;
    width: 2px;
    height: auto;
    background: linear-gradient(180deg, var(--c-blue-200), var(--c-gold-300));
  }
  .timeline__item {
    padding-left: 38px;
    padding-bottom: 30px;
  }
  .timeline__date {
    height: auto;
    line-height: 1.3;
    margin-bottom: 8px;
  }
  .timeline__node {
    position: absolute;
    left: 0;
    top: 4px;
    margin-bottom: 0;
  }
  .section--navy .timeline::before {
    background: linear-gradient(180deg, var(--c-gold-400), var(--c-blue-400));
  }
}

/* ==========================================================================
   12 数据素养能力枢纽图
   ========================================================================== */
.capability {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: clamp(28px, 4vw, 56px);
  align-items: center;
}

.capability__figure {
  width: 100%;
  max-width: 520px;
  margin-inline: auto;
}

.capability__figure svg {
  width: 100%;
  height: auto;
  overflow: visible;
}

.capability__list {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.capability__item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 16px;
  align-items: start;
  padding: 16px 18px;
  background: var(--c-surface);
  border: 1px solid var(--c-line);
  border-left: 3px solid var(--c-blue-600);
  border-radius: var(--radius-sm);
  transition: box-shadow var(--dur) var(--ease-out);
}

.capability__item:hover {
  box-shadow: var(--shadow-sm);
}

.capability__item:nth-child(2) { border-left-color: var(--c-gold-500); }
.capability__item:nth-child(3) { border-left-color: var(--c-blue-400); }
.capability__item:nth-child(4) { border-left-color: var(--c-navy-700); }
.capability__item:nth-child(5) { border-left-color: var(--c-gold-600); }

.capability__role {
  display: inline-block;
  padding: 3px 10px;
  font-size: var(--fs-xs);
  font-weight: var(--fw-bold);
  color: var(--c-blue-700);
  background: var(--c-blue-50);
  border-radius: var(--radius-pill);
}

.capability__name {
  font-size: var(--fs-h4);
  font-weight: var(--fw-bold);
  color: var(--c-navy-900);
  margin-bottom: 4px;
}

.capability__text {
  font-size: var(--fs-sm);
  color: var(--c-ink-2);
}

@media (max-width: 980px) {
  .capability {
    grid-template-columns: minmax(0, 1fr);
  }
}

/* ==========================================================================
   13 表格
   ========================================================================== */
.table-wrap {
  width: 100%;
  overflow-x: auto;
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  background: var(--c-surface);
  -webkit-overflow-scrolling: touch;
}

.table {
  min-width: 640px;
  font-size: var(--fs-sm);
}

.table caption {
  caption-side: top;
  text-align: left;
  padding: 20px 24px 0;
  font-size: var(--fs-h4);
  font-weight: var(--fw-bold);
  color: var(--c-navy-900);
}

.table thead th {
  background: var(--c-navy-900);
  color: #fff;
  font-weight: var(--fw-bold);
  font-size: var(--fs-sm);
  text-align: left;
  padding: 15px 20px;
  white-space: nowrap;
}

.table tbody td {
  padding: 16px 20px;
  border-top: 1px solid var(--c-line);
  vertical-align: top;
  color: var(--c-ink-2);
}

.table tbody tr:nth-child(even) {
  background: var(--c-blue-50);
}

.table tbody tr:hover {
  background: var(--c-blue-100);
}

.table tbody td:first-child {
  color: var(--c-navy-900);
  font-weight: var(--fw-bold);
  white-space: nowrap;
}

.table td .cell-note {
  display: block;
  font-size: var(--fs-xs);
  color: var(--c-ink-3);
  margin-top: 4px;
}

.table--award tbody td:nth-child(2) {
  font-family: var(--font-serif);
  font-size: 1.0625rem;
  font-weight: var(--fw-bold);
  color: var(--c-gold-600);
  white-space: nowrap;
}

.table-scroll-hint {
  display: none;
  font-size: var(--fs-xs);
  color: var(--c-ink-3);
  margin-top: 8px;
}

@media (max-width: 720px) {
  .table-scroll-hint {
    display: block;
  }
}

/* 窄屏：表格改为「卡片 + 字段标签」堆叠，避免横向滚动与内容被裁切。
   依赖每个 <td> 上的 data-label 属性提供字段名。 */
@media (max-width: 720px) {
  .table-wrap {
    border: 0;
    border-radius: 0;
    background: transparent;
    overflow: visible;
  }

  .table {
    display: block;
    min-width: 0;
  }

  .table caption {
    display: block;
    width: 100%;
    box-sizing: border-box;
    padding: 0 0 16px;
    text-align: left;
  }

  .table thead {
    display: none;
  }

  .table tbody,
  .table tr,
  .table td {
    display: block;
    width: auto;
  }

  .table tbody tr {
    margin-bottom: 14px;
    padding: 4px 0;
    background: var(--c-surface);
    border: 1px solid var(--c-line);
    border-radius: var(--radius);
    box-shadow: var(--shadow-xs);
  }

  .table tbody tr:nth-child(even),
  .table tbody tr:hover {
    background: var(--c-surface);
  }

  .table tbody td {
    display: grid;
    grid-template-columns: 88px minmax(0, 1fr);
    gap: 10px;
    padding: 10px 18px;
    border-top: 0;
  }

  /* 字段名固定在第一列；单元格内的元素一律排到第二列，
     避免「正文 + 补充说明」这类多子节点内容错位到标签列。 */
  .table tbody td::before {
    grid-column: 1;
    content: attr(data-label);
    font-size: var(--fs-xs);
    font-weight: var(--fw-bold);
    color: var(--c-ink-3);
    line-height: 1.9;
  }

  .table tbody td > * {
    grid-column: 2;
  }

  /* 首列作为卡片标题 */
  .table tbody td:first-child {
    display: block;
    padding: 16px 18px 12px;
    font-size: 1.0625rem;
    font-weight: var(--fw-black);
    white-space: normal;
    border-bottom: 1px dashed var(--c-line);
  }

  .table tbody td:first-child::before {
    display: none;
  }

  .table-scroll-hint {
    display: none;
  }
}

/* ==========================================================================
   14 图片展示块
   ========================================================================== */
.figure {
  margin: 0;
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--c-surface);
  box-shadow: var(--shadow-sm);
}

.figure img {
  width: 100%;
}

.figure figcaption {
  padding: 14px 20px;
  font-size: var(--fs-xs);
  color: var(--c-ink-3);
  border-top: 1px solid var(--c-line);
  background: var(--c-surface-2);
}

/* 报名海报：受控宽度 */
.poster-figure {
  max-width: 420px;
  margin-inline: auto;
}

/* --- 受控展示 + 浏览器原生查看大图 ---
   说明图原始尺寸远大于版心宽度（例如 700×8750 的长图），
   直接 100% 铺满会被放大到模糊且占满整屏，因此统一限制展示宽度。 */
.figure--bounded {
  max-width: 560px;
  margin-inline: auto;
}

.figure__media {
  display: block;
  position: relative;
  cursor: zoom-in;
}

.figure__media img {
  display: block;
  width: 100%;
  height: auto;
  transition: opacity var(--dur) var(--ease-out);
}

.figure__media:hover img,
.figure__media:focus-visible img {
  opacity: 0.9;
}

/* 超长图只展示顶部一段，底部渐隐提示「还有更多」，
   完整内容交给浏览器原生查看（新标签页按原始比例打开）。 */
.figure--preview .figure__media {
  max-height: 460px;
  overflow: hidden;
}

.figure--preview .figure__media::after {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 130px;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0), #ffffff 90%);
  pointer-events: none;
}

/* 图片下方的「来源说明 + 查看大图」行
   提升一级选择器，避免被 .figure figcaption 的基础样式覆盖 */
.figure .figure__caption {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 18px;
  padding: 16px 20px;
}

.figure .figure__caption > span {
  font-size: var(--fs-xs);
  color: var(--c-ink-3);
}

@media (max-width: 620px) {
  .figure--preview .figure__media {
    max-height: 320px;
  }

  .figure .figure__caption {
    justify-content: center;
    text-align: center;
  }
}

/* ==========================================================================
   15 引述 / 提示块
   ========================================================================== */
.quote-band {
  position: relative;
  padding: clamp(28px, 4vw, 48px);
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, var(--c-navy-900), var(--c-navy-700));
  color: #fff;
  overflow: hidden;
}

.quote-band::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.05) 1px, transparent 1px);
  background-size: 44px 44px;
  pointer-events: none;
}

.quote-band__inner {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  gap: clamp(20px, 3vw, 36px);
  flex-wrap: wrap;
}

.quote-band__mark {
  font-family: var(--font-serif);
  font-size: 3.5rem;
  font-weight: var(--fw-bold);
  line-height: 1;
  color: var(--c-gold-500);
  opacity: 0.85;
}

.quote-band__text {
  flex: 1 1 320px;
  font-size: var(--fs-lead);
  color: #fff;
}

.quote-band__meta {
  font-size: var(--fs-sm);
  color: var(--c-gold-300);
  margin-top: 10px;
}

.callout {
  display: flex;
  gap: 16px;
  padding: 20px 24px;
  border-radius: var(--radius);
  background: var(--c-gold-50);
  border: 1px solid var(--c-gold-300);
}

.callout__icon {
  flex: none;
  width: 22px;
  height: 22px;
  color: var(--c-gold-600);
}

.callout__title {
  font-size: var(--fs-sm);
  font-weight: var(--fw-bold);
  color: var(--c-gold-700);
  margin-bottom: 4px;
}

.callout p {
  font-size: var(--fs-sm);
  color: var(--c-ink-2);
}

/* 要点列表 */
.bullets {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.bullets li {
  position: relative;
  padding-left: 26px;
  font-size: var(--fs-sm);
  color: var(--c-ink-2);
}

.bullets li::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 0.6em;
  width: 8px;
  height: 8px;
  border-radius: 2px;
  background: var(--c-blue-500);
  rotate: 45deg;
}

.section--navy .bullets li {
  color: var(--c-on-dark-2);
}

.section--navy .bullets li::before {
  background: var(--c-gold-400);
}

/* ==========================================================================
   16 二维码卡
   ========================================================================== */
.qr-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(20px, 3vw, 28px);
  max-width: 720px;
  margin-inline: auto;
}

.qr-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
  padding: clamp(24px, 3vw, 34px);
  background: var(--c-surface);
  border: 1px solid var(--c-line);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  text-align: center;
  transition: transform var(--dur) var(--ease-out), box-shadow var(--dur) var(--ease-out);
}

.qr-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-md);
}

.qr-card__media {
  width: 100%;
  max-width: 200px;
  padding: 12px;
  background: #fff;
  border: 1px solid var(--c-line);
  border-radius: var(--radius-sm);
}

.qr-card__title {
  font-size: var(--fs-h4);
}

.qr-card__desc {
  font-size: var(--fs-sm);
  color: var(--c-ink-3);
}

/* 二维码下方的直达入口（解决电脑端无法扫码的问题） */
.qr-card__action {
  margin-top: auto;
  width: 100%;
}

.qr-hint {
  max-width: 720px;
  margin: 18px auto 0;
  padding-top: 16px;
  border-top: 1px dashed var(--c-line);
  font-size: var(--fs-xs);
  color: var(--c-ink-3);
  text-align: center;
}

@media (max-width: 620px) {
  .qr-grid {
    grid-template-columns: minmax(0, 1fr);
  }
}

/* ==========================================================================
   17 Logo 墙
   ========================================================================== */
.logo-wall {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 16px;
}

.logo-slot {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 6px;
  min-height: 96px;
  padding: 18px;
  border: 1px dashed var(--c-line-strong);
  border-radius: var(--radius-sm);
  background: var(--c-surface);
  text-align: center;
  transition: border-color var(--dur) var(--ease-out), background-color var(--dur) var(--ease-out);
}

.logo-slot:hover {
  border-color: var(--c-blue-400);
  background: var(--c-blue-50);
}

.logo-slot__name {
  font-size: var(--fs-sm);
  font-weight: var(--fw-bold);
  color: var(--c-navy-900);
}

.logo-slot__hint {
  font-size: var(--fs-xs);
  color: var(--c-ink-4);
}

/* 已填入校徽的联盟单位卡片：实线边框（不再是占位虚线），校徽统一按高度对齐 */
.logo-slot--filled {
  gap: 10px;
  min-height: 150px;
  border-style: solid;
  border-color: var(--c-line);
}

.logo-slot__img {
  height: 72px;
  width: auto;
  max-width: 100%;
  object-fit: contain;
}

.section--navy .logo-slot {
  background: rgba(255, 255, 255, 0.04);
  border-color: rgba(255, 255, 255, 0.18);
}

.section--navy .logo-slot__name {
  color: #fff;
}

/* ==========================================================================
   18 折叠面板
   ========================================================================== */
.accordion {
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  background: var(--c-surface);
  overflow: hidden;
}

.accordion + .accordion {
  margin-top: 14px;
}

.accordion__trigger {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  width: 100%;
  padding: 18px 24px;
  text-align: left;
  font-size: var(--fs-sm);
  font-weight: var(--fw-bold);
  color: var(--c-navy-900);
  transition: background-color var(--dur-fast) var(--ease-out);
}

.accordion__trigger:hover {
  background: var(--c-surface-2);
}

.accordion__icon {
  position: relative;
  flex: none;
  width: 16px;
  height: 16px;
}

.accordion__icon::before,
.accordion__icon::after {
  content: "";
  position: absolute;
  background: var(--c-blue-600);
  border-radius: 2px;
  transition: transform var(--dur) var(--ease-out);
}

.accordion__icon::before {
  left: 0;
  top: 7px;
  width: 16px;
  height: 2px;
}

.accordion__icon::after {
  left: 7px;
  top: 0;
  width: 2px;
  height: 16px;
}

.accordion__trigger[aria-expanded="true"] .accordion__icon::after {
  transform: scaleY(0);
}

.accordion__panel {
  display: none;
  padding: 0 24px 24px;
  border-top: 1px solid var(--c-line);
}

.accordion__panel.is-open {
  display: block;
}

.accordion__panel > :first-child {
  margin-top: 20px;
}

/* ==========================================================================
   19 行动号召（CTA）
   ========================================================================== */
.cta-band {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  padding-block: clamp(48px, 6vw, 88px);
  background-color: var(--c-navy-950);
  background-image:
    radial-gradient(90% 120% at 15% 10%, rgba(30, 111, 186, 0.42), transparent 60%),
    radial-gradient(80% 100% at 85% 90%, rgba(200, 162, 74, 0.20), transparent 62%),
    linear-gradient(140deg, #061530, #0e2a58);
  color: #fff;
  text-align: center;
}

.cta-band::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.05) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(90% 100% at 50% 50%, #000, transparent 85%);
  -webkit-mask-image: radial-gradient(90% 100% at 50% 50%, #000, transparent 85%);
  pointer-events: none;
}

.cta-band h2 {
  color: #fff;
  margin-bottom: 16px;
}

.cta-band .eyebrow {
  color: var(--c-gold-400);
}

.cta-band p {
  color: var(--c-on-dark-2);
  max-width: 44em;
  margin-inline: auto;
  font-size: var(--fs-lead);
}

.cta-band .btn-group {
  margin-top: 32px;
  justify-content: center;
}

/* ==========================================================================
   20 页脚
   ========================================================================== */
.site-footer {
  background: var(--c-navy-950);
  color: var(--c-on-dark-2);
  padding-top: clamp(48px, 6vw, 76px);
  font-size: var(--fs-sm);
}

.footer__grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1.2fr 1.2fr;
  gap: clamp(24px, 4vw, 48px);
  padding-bottom: clamp(32px, 4vw, 48px);
}

.footer__title {
  font-size: var(--fs-sm);
  font-weight: var(--fw-bold);
  color: #fff;
  margin-bottom: 18px;
  letter-spacing: 0.02em;
}

.footer__brand {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 18px;
}

.footer__desc {
  color: var(--c-on-dark-3);
  line-height: 1.85;
  max-width: 34em;
}

.footer__links {
  display: flex;
  flex-direction: column;
  gap: 11px;
}

.footer__links a {
  color: var(--c-on-dark-2);
}

.footer__links a:hover {
  color: var(--c-gold-400);
}

.footer__contact {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer__contact-item {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  color: var(--c-on-dark-2);
}

.footer__contact-item svg {
  flex: none;
  width: 16px;
  height: 16px;
  margin-top: 4px;
  color: var(--c-gold-400);
}

.footer__contact-item a {
  color: var(--c-on-dark-2);
  word-break: break-all;
}

.footer__contact-item a:hover {
  color: var(--c-gold-400);
}

.footer__qr {
  display: flex;
  gap: 14px;
}

.footer__qr-item {
  text-align: center;
}

.footer__qr-item img {
  width: 84px;
  height: 84px;
  padding: 5px;
  background: #fff;
  border-radius: var(--radius-xs);
}

.footer__qr-item span {
  display: block;
  margin-top: 8px;
  font-size: var(--fs-xs);
  color: var(--c-on-dark-3);
}

.footer__bottom {
  border-top: 1px solid var(--c-on-dark-line);
  padding-block: 22px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 24px;
  align-items: center;
  justify-content: space-between;
  font-size: var(--fs-xs);
  color: var(--c-on-dark-3);
}

.footer__bottom a {
  color: var(--c-on-dark-3);
}

.footer__bottom a:hover {
  color: var(--c-gold-400);
}

@media (max-width: 980px) {
  .footer__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 620px) {
  .footer__grid {
    grid-template-columns: minmax(0, 1fr);
  }
}

/* --- 关注我们（官方账号入口）-------------------------------------------
   放在页脚 4 栏与版权行之间，作为独立一条通栏。
   平台标识只用品牌色小圆点，不绘制第三方 logo，避免图形失真。 */
.footer__follow {
  border-top: 1px solid var(--c-on-dark-line);
  padding-block: clamp(24px, 3vw, 34px);
}

.footer__follow-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
  gap: clamp(24px, 3vw, 44px);
  align-items: center;
}

.footer__official {
  display: flex;
  align-items: center;
  gap: 18px;
}

.footer__official-qr {
  flex: none;
  width: 124px;
  height: 124px;
  padding: 7px;
  background: #fff;
  border-radius: var(--radius-sm);
}

.footer__official-name {
  font-size: var(--fs-h4);
  font-weight: var(--fw-bold);
  color: #fff;
  margin-bottom: 8px;
}

.footer__official-hint {
  font-size: var(--fs-xs);
  color: var(--c-on-dark-3);
  line-height: 1.7;
}

/* 平台列表 */
.social-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.social-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 40px;
  padding: 0 16px;
  font-size: var(--fs-xs);
  font-weight: var(--fw-medium);
  color: var(--c-on-dark-2);
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--c-on-dark-line);
  border-radius: var(--radius-pill);
  transition: color var(--dur-fast) var(--ease-out),
    border-color var(--dur-fast) var(--ease-out),
    background-color var(--dur-fast) var(--ease-out);
}

a.social-link:hover {
  color: #fff;
  border-color: var(--c-gold-500);
  background: rgba(200, 162, 74, 0.14);
}

/* 图标库容器：承载 <symbol> 定义但自身不占位、不渲染 */
.icon-sprite {
  position: absolute;
  width: 0;
  height: 0;
  overflow: hidden;
}

.social-link__icon {
  flex: none;
  width: 18px;
  height: 18px;
  /* 图标为纯路径，fill 继承外层 color，各平台由下面的修饰类给品牌色 */
  fill: currentColor;
}

.social-link--wechat .social-link__icon { color: var(--brand-wechat); }
.social-link--channels .social-link__icon { color: var(--brand-channels); }
.social-link--bilibili .social-link__icon { color: var(--brand-bilibili); }
.social-link--douyin .social-link__icon { color: var(--brand-douyin); }
.social-link--xiaohongshu .social-link__icon { color: var(--brand-xiaohongshu); }

/* 小红书标志是横排文字商标（宽高比约 2.8:1），单独给它横向尺寸，
   这样不重复写「小红书」文字也能看清。 */
.social-link--xiaohongshu .social-link__icon {
  width: 50px;
  height: 18px;
}

.social-link__ext {
  font-size: 0.75em;
  opacity: 0.65;
  transition: transform var(--dur-fast) var(--ease-out);
}

a.social-link:hover .social-link__ext {
  transform: translate(2px, -2px);
}

/* 没有公开链接的平台（如微信视频号）：同样式但不可点击 */
.social-link--static {
  cursor: default;
  color: var(--c-on-dark-3);
}

/* 平台账号名（如微信视频号那一条展示的「数智星海开放社区」）
   用一条竖线与平台名分开，读起来是「平台 · 账号」，并比平台名稍亮 */
.social-link__name {
  padding-left: 9px;
  margin-left: 2px;
  border-left: 1px solid var(--c-on-dark-line);
  font-size: var(--fs-xs);
  color: var(--c-on-dark-2);
}

@media (max-width: 900px) {
  .footer__follow-grid {
    grid-template-columns: minmax(0, 1fr);
  }
}

@media (max-width: 430px) {
  .footer__official-qr {
    width: 104px;
    height: 104px;
    padding: 6px;
  }
}

/* --- 「关注官方账号」卡片块 -------------------------------------------
   用在深色卡片（.card--navy）内，配色按深色底设计。 */
.follow-block {
  margin-top: 22px;
  padding-top: 20px;
  border-top: 1px solid var(--c-on-dark-line);
}

.follow-block__title {
  font-size: var(--fs-sm);
  font-weight: var(--fw-bold);
  color: #fff;
  margin-bottom: 16px;
}

.follow-block__official {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 18px;
}

.follow-block__qr {
  flex: none;
  width: 112px;
  height: 112px;
  padding: 6px;
  background: #fff;
  border-radius: var(--radius-sm);
}

.follow-block__name {
  font-size: var(--fs-sm);
  font-weight: var(--fw-bold);
  color: #fff;
  margin-bottom: 6px;
}

.follow-block__hint {
  font-size: var(--fs-xs);
  color: var(--c-on-dark-3);
  line-height: 1.7;
}

@media (max-width: 430px) {
  .follow-block__official {
    flex-direction: column;
    align-items: flex-start;
  }
}

/* 浅色底上的联系方式列表（与页脚同构，配色切换为浅色主题） */
.contact-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.contact-list__item {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  color: var(--c-ink-2);
  font-size: var(--fs-sm);
}

.contact-list__item svg {
  flex: none;
  width: 16px;
  height: 16px;
  margin-top: 4px;
  color: var(--c-gold-600);
}

.contact-list__item a {
  color: var(--c-blue-600);
  word-break: break-all;
}

.contact-list__item a:hover {
  color: var(--c-blue-700);
}

/* ==========================================================================
   21 回到顶部
   ========================================================================== */
.back-to-top {
  position: fixed;
  right: clamp(16px, 3vw, 32px);
  bottom: clamp(16px, 3vw, 32px);
  z-index: var(--z-sticky);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background: var(--c-navy-900);
  color: #fff;
  box-shadow: var(--shadow-md);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity var(--dur) var(--ease-out), transform var(--dur) var(--ease-out),
    visibility var(--dur), background-color var(--dur-fast) var(--ease-out);
}

.back-to-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: none;
}

.back-to-top:hover {
  background: var(--c-blue-600);
}

.back-to-top svg {
  width: 18px;
  height: 18px;
}

/* ==========================================================================
   22 赛程倒计时
   由 assets/js/site.js 的 initCountdown() 驱动，节点日期来自 data-* 属性。
   无 JS 时仅显示静态日期文案（.countdown__grid 带 hidden，不会露出 --）。
   ========================================================================== */
.countdown {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.countdown__label {
  font-size: var(--fs-xs);
  font-weight: var(--fw-bold);
  letter-spacing: 0.06em;
  color: var(--c-gold-300);
}

.countdown__grid {
  display: flex;
  align-items: flex-start;
  gap: clamp(8px, 1.4vw, 16px);
}

/* hidden 属性优先级要高于 display:flex */
.countdown__grid[hidden] {
  display: none;
}

.countdown__cell {
  display: flex;
  flex-direction: column;
  align-items: center;
  min-width: 46px;
}

.countdown__num {
  font-family: var(--font-serif);
  font-size: clamp(1.5rem, 3.4vw, 2rem);
  font-weight: var(--fw-bold);
  font-variant-numeric: tabular-nums;
  line-height: 1;
  color: #fff;
}

.countdown__unit {
  margin-top: 6px;
  font-size: 0.6875rem;
  font-style: normal;
  color: var(--c-on-dark-3);
}

.countdown__sep {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  line-height: 1.5;
  color: var(--c-on-dark-line);
}

.countdown__note {
  font-size: var(--fs-xs);
  color: var(--c-on-dark-3);
}

/* 放进 Hero 速览面板时去掉外层容器样式，避免「盒子套盒子」 */
.hero__panel .countdown {
  padding-bottom: 20px;
  margin-bottom: 18px;
  border-bottom: 1px solid var(--c-on-dark-line);
}

@media (max-width: 430px) {
  .countdown__cell {
    min-width: 40px;
  }
  .countdown__num {
    font-size: 1.375rem;
  }
}

/* ==========================================================================
   23 品牌标识 · 横版组合（浅色卡片内使用）
   素材 docs/logo/logo.png 自带约 31% 的上下留白，此处用等比例裁切容器收紧，
   图片文件本身不做任何裁剪、改色或重绘。
   ========================================================================== */
.org-lockup {
  display: block;
  width: min(300px, 100%);
  aspect-ratio: 1702 / 483;
  overflow: hidden;
  margin-bottom: 10px;
}

.org-lockup img {
  display: block;
  position: relative;
  top: 50%;
  width: 100%;
  height: auto;
  transform: translateY(-50%);
}

@media (max-width: 430px) {
  .org-lockup {
    width: min(240px, 100%);
  }
}