/* ==========================================================================
   买球平台官网 · 共享基础样式 /assets/site.css
   深墨蓝工作台面 + 米灰纸面 + 荧光青交互 + 暖橙步骤
   ========================================================================== */

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

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

html[data-nav-lock] { overflow: hidden; }

body,
h1, h2, h3, h4, h5, h6,
p, figure, blockquote, dl, dd, ul, ol { margin: 0; }

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

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

button, input, select, textarea { font: inherit; color: inherit; }

button { background: none; border: 0; padding: 0; cursor: pointer; }

a { color: inherit; text-decoration: none; }

:where(a, button, summary, [tabindex]):focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
  border-radius: 2px;
}

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

/* ---------- 2. 变量 ---------- */
:root {
  --ink: #0B1B2B;
  --ink-2: #12293D;
  --ink-3: #0E2233;
  --cream: #F1EAD9;
  --line: #CFC6B4;
  --cyan: #23F0C8;
  --cyan-soft: #8FF7E2;
  --orange: #FF7A29;
  --silver: #D5DEE7;
  --muted: #8A9AA8;
  --text: #F4F7FA;
  --warn: #E24B2E;
  --paper-ink: #2A2318;

  --shell-max: 1240px;
  --gutter: clamp(18px, 4vw, 48px);

  --hairline: rgba(207, 198, 180, 0.18);
  --hairline-strong: rgba(207, 198, 180, 0.34);

  --dur: 160ms;
  --ease: cubic-bezier(0.2, 0.75, 0.3, 1);

  --font-sans: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
  --font-serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", Georgia, serif;
  --font-mono: "JetBrains Mono", "SFMono-Regular", ui-monospace, "Cascadia Mono", Consolas, "Liberation Mono", monospace;
}

/* ---------- 3. 基础排版 ---------- */
body {
  background-color: var(--ink);
  background-image:
    radial-gradient(1100px 560px at 82% -12%, rgba(35, 240, 200, 0.07), transparent 62%),
    radial-gradient(820px 460px at -6% 4%, rgba(255, 122, 41, 0.05), transparent 58%);
  background-repeat: no-repeat;
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.75;
  letter-spacing: 0.01em;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

@media (min-width: 1024px) {
  body { font-size: 17px; }
}

h1, h2, h3, h4 { line-height: 1.16; font-weight: 700; }

.display-1 {
  font-size: clamp(38px, 5.4vw, 84px);
  font-weight: 900;
  line-height: 1.02;
  letter-spacing: -0.02em;
  font-stretch: 87.5%;
}

.display-2 {
  font-size: clamp(28px, 3.6vw, 40px);
  font-weight: 900;
  line-height: 1.08;
  letter-spacing: -0.015em;
  font-stretch: 87.5%;
}

.section-title {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(22px, 2.4vw, 28px);
  line-height: 1.28;
  letter-spacing: 0;
}

.lede {
  font-size: clamp(16px, 1.5vw, 20px);
  line-height: 1.7;
  color: var(--silver);
  max-width: 62ch;
}

.prose {
  max-width: 62ch;
  line-height: 1.75;
}

.prose p + p { margin-top: 1em; }

.prose h3 { margin-top: 1.6em; margin-bottom: 0.5em; font-size: 20px; }

.mono {
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.02em;
}

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

.eyebrow::before {
  content: "";
  width: 22px;
  height: 1px;
  background: var(--cyan);
}

/* ---------- 4. 容器与布局工具 ---------- */
.shell {
  width: 100%;
  max-width: var(--shell-max);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.grid {
  display: grid;
  gap: clamp(20px, 3vw, 40px);
}

.grid--12 {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(20px, 3vw, 40px);
}

.span-3 { grid-column: span 3; }
.span-4 { grid-column: span 4; }
.span-5 { grid-column: span 5; }
.span-6 { grid-column: span 6; }
.span-7 { grid-column: span 7; }
.span-8 { grid-column: span 8; }
.span-9 { grid-column: span 9; }
.span-12 { grid-column: span 12; }

.rule {
  height: 1px;
  border: 0;
  background: var(--hairline);
  margin-block: clamp(28px, 4vw, 56px);
}

.status-dot {
  display: inline-block;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--cyan);
  vertical-align: middle;
}

.status-dot--orange { background: var(--orange); }

.date-line {
  display: flex;
  align-items: center;
  gap: 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.date-line::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--hairline);
}

/* ---------- 5. 通用按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 18px;
  border: 1px solid var(--hairline-strong);
  border-radius: 2px;
  background: transparent;
  color: var(--text);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.02em;
  line-height: 1.4;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

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

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

.btn--ghost {
  padding: 8px 14px;
  font-size: 13px;
  font-weight: 500;
  border-color: var(--hairline-strong);
  color: var(--silver);
}

.btn--accent {
  background: var(--cyan);
  border-color: var(--cyan);
  color: var(--ink);
  font-weight: 700;
}

.btn--accent:hover {
  background: var(--cyan-soft);
  border-color: var(--cyan-soft);
  color: var(--ink);
}

.btn--step {
  background: var(--orange);
  border-color: var(--orange);
  color: #20120A;
  font-weight: 700;
}

.btn--step:hover {
  background: #FF9455;
  border-color: #FF9455;
  color: #20120A;
}

.btn--quiet {
  padding: 2px 0;
  border-color: transparent;
  border-bottom: 1px solid var(--cyan);
  border-radius: 0;
  color: var(--cyan-soft);
  font-weight: 500;
}

.btn--quiet:hover { color: var(--cyan); border-bottom-color: var(--cyan); }

/* ==========================================================================
   6. 页头
   ========================================================================== */
.site-header {
  --top-h: 36px;
  --main-h: 64px;
  position: sticky;
  top: 0;
  z-index: 80;
  background: var(--ink);
  border-bottom: 1px solid var(--hairline);
  transition: border-color var(--dur) var(--ease);
}

.site-header[data-scrolled] {
  --top-h: 0px;
  --main-h: 52px;
  border-bottom-color: rgba(35, 240, 200, 0.3);
}

/* 跳转链接 */
.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 300;
  padding: 10px 16px;
  background: var(--cyan);
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 700;
  border-radius: 2px;
  transform: translateY(-220%);
  transition: transform var(--dur) var(--ease);
}

.skip-link:focus,
.skip-link:focus-visible {
  transform: translateY(0);
  outline: 2px solid var(--ink);
  outline-offset: 2px;
}

/* 滚动进度线 */
.scroll-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  background: var(--cyan);
  transform: scaleX(0);
  transform-origin: 0 50%;
  pointer-events: none;
  z-index: 3;
}

/* 顶层信息条 */
.header-top {
  height: var(--top-h);
  overflow: hidden;
  border-bottom: 1px solid rgba(207, 198, 180, 0.14);
  transition: height var(--dur) var(--ease), opacity var(--dur) var(--ease);
}

.site-header[data-scrolled] .header-top {
  opacity: 0;
  border-bottom-color: transparent;
}

.header-top__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: clamp(12px, 3vw, 32px);
  height: 36px;
}

.header-top__brand {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.2em;
  color: var(--cyan-soft);
  white-space: nowrap;
}

.header-top__meta {
  display: flex;
  align-items: center;
  gap: clamp(10px, 2vw, 22px);
  min-width: 0;
}

.stamp {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 3px 8px;
  border: 1px solid rgba(207, 198, 180, 0.22);
  border-radius: 2px;
  background: transparent;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.4;
  color: var(--muted);
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.stamp:hover,
.stamp[aria-expanded="true"] {
  border-color: var(--cyan);
  color: var(--silver);
}

.stamp__dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--cyan);
  animation: stamp-blink 700ms var(--ease) 1 both;
}

@keyframes stamp-blink {
  0% { opacity: 0.15; transform: scale(0.5); }
  12% { opacity: 1; transform: scale(1); }
  100% { opacity: 1; transform: scale(1); }
}

.stamp__label { white-space: nowrap; }

.stamp__value { color: var(--cyan-soft); }

.header-top__icp {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--muted);
  white-space: nowrap;
}

.header-top__link {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--silver);
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.header-top__link:hover {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

/* 主层 */
.header-main {
  height: var(--main-h);
  transition: height var(--dur) var(--ease);
}

.header-main__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: clamp(16px, 3vw, 40px);
  height: 100%;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

.brand__mark {
  width: 9px;
  height: 24px;
  background: var(--cyan);
  clip-path: polygon(0 0, 100% 0, 100% 74%, 50% 100%, 0 74%);
  transition: background-color var(--dur) var(--ease);
}

.brand:hover .brand__mark { background: var(--cyan-soft); }

.brand__name {
  font-size: 20px;
  font-weight: 900;
  font-stretch: 87.5%;
  letter-spacing: -0.01em;
  color: var(--text);
}

.brand__sub {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--muted);
  white-space: nowrap;
}

/* 桌面导航 */
.site-nav {
  display: flex;
  align-items: center;
  gap: clamp(16px, 2.4vw, 34px);
  min-width: 0;
}

.site-nav__head { display: none; }

.site-nav__title { display: none; }

.site-nav__list {
  display: flex;
  align-items: center;
  gap: clamp(14px, 2.2vw, 30px);
}

.site-nav__link {
  position: relative;
  display: inline-block;
  padding: 8px 2px;
  font-size: 15px;
  font-weight: 500;
  line-height: 1.4;
  color: var(--text);
  white-space: nowrap;
  transition: color var(--dur) var(--ease);
}

.site-nav__link::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  background: var(--cyan);
  transform: scaleX(0);
  transform-origin: 0 50%;
  transition: transform var(--dur) var(--ease);
}

.site-nav__link:hover { color: var(--cyan); }
.site-nav__link:hover::after,
.site-nav__link:focus-visible::after { transform: scaleX(1); }

.site-nav__link[aria-current="page"] { color: var(--cyan); }
.site-nav__link[aria-current="page"]::after { transform: scaleX(1); }

.site-nav__save { flex-shrink: 0; }

/* 移动开关 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border: 1px solid var(--hairline-strong);
  border-radius: 2px;
  transition: border-color var(--dur) var(--ease);
}

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

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

.nav-toggle__bar {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--cyan);
}

.nav-toggle__text {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--silver);
}

.nav-close {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 10px;
  border: 1px solid var(--hairline-strong);
  border-radius: 2px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--silver);
}

.nav-close:hover { border-color: var(--cyan); color: var(--cyan); }

.nav-close__text { letter-spacing: 0.1em; }

/* 遮罩 */
.nav-scrim {
  position: fixed;
  inset: 0;
  z-index: 60;
  background: rgba(6, 14, 22, 0.72);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--dur) var(--ease);
}

.nav-scrim[data-open] {
  opacity: 1;
  pointer-events: auto;
}

@media (min-width: 961px) {
  .nav-scrim { display: none; }
}

/* 校订日期说明浮层 */
.stamp-note {
  position: absolute;
  top: calc(100% + 10px);
  right: var(--gutter);
  z-index: 120;
  display: none;
  width: min(360px, calc(100vw - var(--gutter) * 2));
  padding: 18px 20px;
  background: var(--cream);
  color: var(--paper-ink);
  border: 1px solid var(--line);
  border-top: 2px solid var(--cyan);
  box-shadow: 0 26px 48px rgba(0, 0, 0, 0.45);
}

.stamp-note[data-open] { display: block; }

.stamp-note__title {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: #6B5F49;
  margin-bottom: 8px;
}

.stamp-note__body {
  font-size: 14px;
  line-height: 1.7;
  color: var(--paper-ink);
}

.stamp-note__mono {
  font-family: var(--font-mono);
  font-size: 13px;
  background: rgba(11, 27, 43, 0.08);
  padding: 1px 4px;
}

.stamp-note__link {
  display: inline-block;
  margin-top: 12px;
  font-family: var(--font-mono);
  font-size: 13px;
  color: #0B4E43;
  border-bottom: 1px solid currentColor;
}

.stamp-note__link:hover { color: var(--warn); }

/* ==========================================================================
   7. 页脚
   ========================================================================== */
.site-footer {
  background: var(--ink);
  border-top: 1px solid var(--hairline-strong);
  margin-top: clamp(56px, 8vw, 120px);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1.2fr;
  gap: clamp(24px, 4vw, 56px);
  padding-block: clamp(40px, 6vw, 72px);
}

.footer-brand__name {
  font-size: 22px;
  font-weight: 900;
  font-stretch: 87.5%;
  letter-spacing: -0.01em;
  color: var(--text);
}

.footer-brand__note {
  margin-top: 14px;
  max-width: 30ch;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

.footer-brand__meta {
  margin-top: 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--cyan-soft);
}

.footer-col__title {
  margin-bottom: 16px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--cyan-soft);
}

.footer-list li + li { margin-top: 10px; }

.footer-link {
  display: inline-block;
  font-size: 14px;
  color: var(--silver);
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.footer-link:hover {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

.footer-contact li {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 10px;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.65;
  color: var(--silver);
}

.footer-contact__val { word-break: break-word; }

.copy-btn {
  flex-shrink: 0;
  padding: 2px 7px;
  border: 1px solid rgba(35, 240, 200, 0.4);
  border-radius: 2px;
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.5;
  color: var(--cyan-soft);
  transition: background-color var(--dur) var(--ease), color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.copy-btn:hover {
  background: rgba(35, 240, 200, 0.14);
  border-color: var(--cyan);
}

.copy-btn[data-copied] {
  background: var(--cyan);
  border-color: var(--cyan);
  color: var(--ink);
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 28px;
  padding-block: 24px 48px;
  border-top: 1px solid var(--hairline);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

.footer-legal__links {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
}

.footer-legal__link {
  color: var(--muted);
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.footer-legal__link:hover {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

/* ==========================================================================
   8. 页面通用组件（供页面阶段使用）
   ========================================================================== */
.section {
  padding-block: clamp(48px, 7vw, 96px);
  border-top: 1px solid var(--hairline);
}

.section--cream {
  background: var(--cream);
  color: var(--paper-ink);
  border-top-color: rgba(11, 27, 43, 0.14);
}

.section--cream .lede,
.section--cream .prose { color: #3B3325; }

.section--cream .eyebrow { color: #0B4E43; }
.section--cream .eyebrow::before { background: #0B4E43; }

.section__head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: clamp(24px, 3vw, 40px);
}

.panel {
  padding: clamp(20px, 2.6vw, 32px);
  background: var(--ink-2);
  border: 1px solid var(--hairline);
  border-radius: 3px;
}

.panel--cream {
  background: var(--cream);
  color: var(--paper-ink);
  border-color: var(--line);
}

.panel--cream .tag--muted { color: #6B5F49; }

.panel--cut {
  padding: clamp(22px, 3vw, 36px);
  background: var(--ink-2);
  border: 0;
  border-radius: 0;
  clip-path: polygon(0 0, calc(100% - 24px) 0, 100% 24px, 100% 100%, 24px 100%, 0 calc(100% - 24px));
}

/* 标签切片 */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 8px;
  border: 1px solid currentColor;
  border-radius: 2px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.5;
  letter-spacing: 0.06em;
}

.tag--cn { background: var(--cream); color: var(--paper-ink); border-color: var(--line); }
.tag--apple { background: var(--silver); color: var(--ink); border-color: var(--silver); }
.tag--android { background: transparent; color: var(--orange); border-color: var(--orange); }
.tag--cyan { background: var(--cyan); color: var(--ink); border-color: var(--cyan); }
.tag--muted { background: transparent; color: var(--muted); border-color: rgba(138, 154, 168, 0.5); }

/* 三步轨道 */
.step-track {
  position: relative;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(12px, 2vw, 28px);
}

.step-track::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 16px;
  height: 1px;
  background: linear-gradient(90deg, var(--orange), rgba(255, 122, 41, 0.12));
}

.step {
  position: relative;
  padding-top: 44px;
}

.step__no {
  position: absolute;
  top: 0;
  left: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 34px;
  height: 32px;
  padding: 0 8px;
  background: var(--orange);
  color: #20120A;
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 700;
}

.step__title {
  margin-bottom: 6px;
  font-size: 17px;
  font-weight: 700;
}

.step__body {
  font-size: 14px;
  line-height: 1.7;
  color: var(--silver);
}

/* 筛选条 */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding-block: 12px;
  border-top: 1px solid var(--hairline);
  border-bottom: 1px solid var(--hairline);
}

.filter-btn {
  padding: 6px 12px;
  border: 1px solid var(--hairline-strong);
  border-radius: 2px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--silver);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.filter-btn:hover { border-color: var(--cyan); color: var(--cyan); }

.filter-btn[aria-pressed="true"] {
  background: var(--cyan);
  border-color: var(--cyan);
  color: var(--ink);
  font-weight: 700;
}

.filter-status {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--muted);
}

[data-filtered-out] { display: none !important; }

/* 日期索引列表 */
.index-list { border-top: 1px solid var(--hairline); }

.index-item {
  display: grid;
  grid-template-columns: 128px minmax(0, 1fr) auto;
  gap: clamp(12px, 2vw, 28px);
  align-items: baseline;
  padding-block: 18px;
  border-bottom: 1px solid var(--hairline);
}

.index-item__date {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--cyan-soft);
}

.index-item__body { font-size: 16px; line-height: 1.6; }

.index-item__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--muted);
}

/* 面包屑 */
.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding-block: 18px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

.breadcrumbs__link {
  color: var(--silver);
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.breadcrumbs__link:hover { color: var(--cyan); border-bottom-color: var(--cyan); }

.breadcrumbs__sep { color: rgba(138, 154, 168, 0.6); }

.breadcrumbs [aria-current="page"] { color: var(--text); }

/* 说明与边注 */
.note {
  padding: 12px 0 12px 16px;
  border-left: 2px solid var(--cyan);
  font-size: 14px;
  line-height: 1.7;
  color: var(--silver);
}

.callout {
  padding: clamp(18px, 2.4vw, 28px);
  background: var(--cream);
  color: var(--paper-ink);
  border-left: 3px solid var(--orange);
  font-size: 15px;
  line-height: 1.7;
}

/* 图片容器基础规则 */
.media {
  position: relative;
  display: block;
  overflow: hidden;
  background: var(--ink-2);
  border: 1px solid var(--hairline);
  border-radius: 3px;
}

.media::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(35, 240, 200, 0.08) 1px, transparent 1px),
    linear-gradient(90deg, rgba(35, 240, 200, 0.08) 1px, transparent 1px);
  background-size: 32px 32px;
  pointer-events: none;
}

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

.media--16x9 { aspect-ratio: 16 / 9; }
.media--4x3 { aspect-ratio: 4 / 3; }
.media--1x1 { aspect-ratio: 1 / 1; }

.media__glow {
  position: absolute;
  right: -12%;
  bottom: -30%;
  width: 70%;
  aspect-ratio: 1 / 1;
  background: radial-gradient(circle, rgba(35, 240, 200, 0.3), transparent 65%);
  filter: blur(6px);
  pointer-events: none;
}

/* 视口显现 */
[data-reveal] {
  transition: opacity 180ms var(--ease), transform 180ms var(--ease);
}

[data-reveal]:not([data-reveal="in"]) {
  opacity: 0;
  transform: translateY(10px);
}

/* ==========================================================================
   9. 响应式
   ========================================================================== */
@media (max-width: 1100px) {
  .header-top__icp { display: none; }
}

@media (max-width: 960px) {
  .nav-toggle { display: inline-flex; position: relative; z-index: 95; }

  .site-nav {
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    z-index: 90;
    width: min(340px, 86vw);
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 18px;
    padding: 20px var(--gutter) 32px;
    background: var(--ink-2);
    border-right: 1px solid var(--hairline-strong);
    box-shadow: 24px 0 60px rgba(0, 0, 0, 0.45);
    overflow-y: auto;
    transform: translateX(-102%);
    visibility: hidden;
    transition: transform var(--dur) var(--ease), visibility var(--dur) var(--ease);
  }

  .site-nav[data-open] {
    transform: translateX(0);
    visibility: visible;
  }

  .site-nav__head {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    padding-bottom: 14px;
    border-bottom: 1px solid var(--hairline);
  }

  .site-nav__title {
    display: block;
    font-family: var(--font-mono);
    font-size: 12px;
    letter-spacing: 0.2em;
    color: var(--cyan-soft);
  }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }

  .site-nav__link {
    display: block;
    padding: 14px 0 14px 2px;
    border-bottom: 1px solid var(--hairline);
    font-size: 17px;
  }

  .site-nav__link::after { display: none; }

  .site-nav__link[aria-current="page"] {
    padding-left: 12px;
    border-left: 2px solid var(--cyan);
    color: var(--cyan);
  }

  .site-nav__save {
    width: 100%;
    margin-top: 6px;
  }
}

@media (max-width: 900px) {
  .span-3, .span-4 { grid-column: span 3; }
  .span-5, .span-6, .span-7, .span-8, .span-9 { grid-column: span 6; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .index-item { grid-template-columns: 104px minmax(0, 1fr); }
  .index-item__meta { grid-column: 2; }
}

@media (max-width: 720px) {
  .step-track { grid-template-columns: 1fr; gap: 20px; }
  .step-track::before { display: none; }
  .step { padding-top: 40px; }
}

@media (max-width: 640px) {
  .span-3, .span-4, .span-5, .span-6,
  .span-7, .span-8, .span-9, .span-12 { grid-column: 1 / -1; }

  .grid--12 { grid-template-columns: 1fr; }

  .header-top__brand { font-size: 11px; letter-spacing: 0.12em; }
  .stamp__label { display: none; }
  .brand__sub { display: none; }
  .stamp-note { right: var(--gutter); left: var(--gutter); width: auto; }

  .footer-grid { grid-template-columns: 1fr; gap: 28px; }
  .footer-legal { flex-direction: column; align-items: flex-start; }

  .index-item {
    grid-template-columns: 1fr;
    gap: 6px;
  }
  .index-item__meta { grid-column: auto; }

  .filter-status { margin-left: 0; width: 100%; }
}

/* ==========================================================================
   10. 可访问性：动效偏好
   ========================================================================== */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }

  [data-reveal]:not([data-reveal="in"]) {
    opacity: 1;
    transform: none;
  }

  .stamp__dot { animation: none; }
}