/* ============================================================
   球速赛场 · 共享样式表 /assets/site.css
   设计逻辑：技术蓝图式框架 + 珠宝色分区 + 赛场速度感
   ============================================================ */

/* ---------- 1. 基础重置 ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-padding-top: 148px;
}

@media (prefers-reduced-motion: no-preference) {
  html { scroll-behavior: smooth; }
}

body {
  margin: 0;
  background: var(--void);
  color: var(--bone);
  font-family: var(--font-body);
  font-size: var(--fs-18);
  font-weight: 400;
  line-height: 1.9;
  letter-spacing: 0.01em;
  overflow-x: hidden;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(22, 32, 43, 0.5) 1px, transparent 1px),
    linear-gradient(90deg, rgba(22, 32, 43, 0.5) 1px, transparent 1px);
  background-size: clamp(48px, 7vw, 104px) clamp(48px, 7vw, 104px);
}

h1, h2, h3, h4, h5, h6 {
  margin: 0 0 0.5em;
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: -0.02em;
}

p { margin: 0 0 1.2em; }

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

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

a { color: var(--cyan); text-decoration: none; transition: color var(--t-fast); }
a:hover { color: var(--lime); }

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

::selection { background: var(--lime); color: var(--void); }

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

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

[data-section] { scroll-margin-top: 148px; }

/* ---------- 2. CSS 变量 ---------- */
:root {
  --void: #07090F;
  --grid: #16202B;
  --jade: #06302C;
  --indigo: #241542;
  --wine: #4A0F24;
  --lime: #B4FF39;
  --cyan: #35D6FF;
  --amber: #FF9130;
  --bone: #EAF3EE;
  --mist: #93A8A2;

  --font-display: "Noto Sans SC", "Source Han Sans SC", "HarmonyOS Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --font-body: var(--font-display);
  --font-mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  --fs-260: 260px;
  --fs-96: 96px;
  --fs-56: 56px;
  --fs-34: 34px;
  --fs-22: 22px;
  --fs-18: 18px;
  --fs-14: 14px;
  --fs-12: 12px;

  --gutter: clamp(18px, 4vw, 56px);
  --maxw: 1320px;

  --radius-s: 4px;
  --radius-m: clamp(16px, 2.4vw, 30px);
  --radius-l: clamp(22px, 3.4vw, 44px);

  --t-fast: 180ms cubic-bezier(0.2, 0.7, 0.3, 1);
  --t-mid: 480ms cubic-bezier(0.2, 0.7, 0.3, 1);
}

/* ---------- 3. 页头框架 ---------- */
.frame {
  position: sticky;
  top: 0;
  z-index: 60;
  background: rgba(7, 9, 15, 0.93);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--grid);
}

.skip-link {
  position: absolute;
  left: 14px;
  top: 10px;
  z-index: 200;
  transform: translateY(-220%);
  padding: 10px 20px;
  border-radius: 100px;
  background: var(--lime);
  color: var(--void);
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: 700;
  letter-spacing: 0.1em;
  transition: transform var(--t-fast);
}

.skip-link:focus {
  transform: none;
  color: var(--void);
}

/* 顶部坐标条 */
.topbar {
  display: flex;
  align-items: center;
  gap: clamp(12px, 2vw, 26px);
  min-height: 54px;
  padding: 8px var(--gutter);
  border-bottom: 1px solid var(--grid);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--bone);
  font-weight: 800;
  font-size: var(--fs-18);
  letter-spacing: -0.01em;
  white-space: nowrap;
}

.brand:hover { color: var(--bone); }

.brand__mark {
  display: grid;
  place-items: center;
  width: 34px;
  height: 22px;
  border-radius: var(--radius-s);
  background: var(--lime);
  color: var(--void);
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: 600;
  letter-spacing: 0.06em;
  transition: background var(--t-fast);
}

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

.brand__text { display: inline-flex; align-items: baseline; gap: 0.36em; }

.brand__sep { color: var(--lime); }

.brand__sub {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: 500;
  letter-spacing: 0.18em;
  color: var(--mist);
}

.topbar__status {
  display: none;
  align-items: center;
  gap: 9px;
  margin: 0;
  padding-left: clamp(12px, 2vw, 26px);
  border-left: 1px solid var(--grid);
  font-size: var(--fs-14);
  line-height: 1.5;
  color: var(--mist);
}

.pulse {
  flex: 0 0 auto;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--lime);
  animation: pulse-ring 2.4s ease-out infinite;
}

@keyframes pulse-ring {
  0%   { box-shadow: 0 0 0 0 rgba(180, 255, 57, 0.55); }
  70%  { box-shadow: 0 0 0 10px rgba(180, 255, 57, 0); }
  100% { box-shadow: 0 0 0 0 rgba(180, 255, 57, 0); }
}

.topbar__coord {
  display: none;
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: 500;
  letter-spacing: 0.2em;
  color: var(--mist);
  white-space: nowrap;
}

/* 移动导航按钮 */
.nav-toggle {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  margin-left: auto;
  padding: 8px 14px;
  border: 1px solid var(--grid);
  border-radius: 100px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  color: var(--bone);
  transition: border-color var(--t-fast), color var(--t-fast);
}

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

.nav-toggle__bars {
  display: grid;
  gap: 4px;
  width: 16px;
}

.nav-toggle__bars span {
  display: block;
  height: 1.5px;
  background: currentColor;
  transition: transform var(--t-fast);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(1) { transform: translateY(2.75px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(2) { transform: translateY(-2.75px) rotate(-45deg); }

.nav-toggle__label { line-height: 1; }

/* 刻度尺式主导航 */
.navbar {
  display: flex;
  align-items: stretch;
  justify-content: space-between;
  padding: 0 var(--gutter);
}

.navbar__list {
  display: flex;
  flex-wrap: wrap;
  border-left: 1px solid var(--grid);
}

.navbar__link {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 15px clamp(12px, 1.6vw, 26px);
  border-right: 1px solid var(--grid);
  color: var(--bone);
  font-size: var(--fs-18);
  font-weight: 500;
  line-height: 1.4;
  transition: color var(--t-fast), background var(--t-fast);
}

.navbar__link::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  background: linear-gradient(90deg, var(--lime), var(--cyan));
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform var(--t-mid);
}

.navbar__idx {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: 500;
  letter-spacing: 0.1em;
  color: var(--mist);
  transition: color var(--t-fast);
}

.navbar__link:hover {
  color: var(--lime);
  background: rgba(180, 255, 57, 0.05);
}

.navbar__link:hover .navbar__idx { color: var(--lime); }
.navbar__link:hover::after { transform: scaleX(1); }

.navbar__link[aria-current="page"] {
  color: var(--lime);
  font-weight: 800;
}

.navbar__link[aria-current="page"] .navbar__idx { color: var(--lime); }
.navbar__link[aria-current="page"]::after { transform: scaleX(1); }

.navbar__meta {
  display: none;
  align-items: center;
  margin: 0;
  padding: 15px 0;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.18em;
  color: var(--mist);
  white-space: nowrap;
}

/* 左侧章节索引轨 */
.rail {
  display: none;
  position: fixed;
  left: 16px;
  top: 50%;
  transform: translateY(-50%);
  z-index: 50;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  padding: 14px 8px;
  border: 1px solid var(--grid);
  border-radius: 100px;
  background: rgba(7, 9, 15, 0.74);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.rail__title {
  margin: 0 0 4px;
  writing-mode: vertical-rl;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.24em;
  color: var(--mist);
}

.rail__list {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.rail__link {
  display: grid;
  place-items: center;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  color: var(--mist);
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.04em;
  transition: color var(--t-fast), background var(--t-fast);
}

.rail__link:hover { color: var(--lime); background: rgba(180, 255, 57, 0.12); }

.rail__link[aria-current="true"] {
  background: var(--lime);
  color: var(--void);
  font-weight: 600;
}

/* ---------- 4. 页脚 ---------- */
.site-footer {
  position: relative;
  z-index: 1;
  margin-top: clamp(72px, 11vw, 160px);
  padding: clamp(46px, 6vw, 88px) var(--gutter) clamp(120px, 15vw, 170px);
  border-top: 1px solid var(--grid);
  background:
    radial-gradient(120% 90% at 8% 0%, rgba(36, 21, 66, 0.95), transparent 58%),
    radial-gradient(110% 85% at 96% 4%, rgba(6, 48, 44, 0.92), transparent 56%),
    radial-gradient(90% 80% at 50% 104%, rgba(74, 15, 36, 0.6), transparent 62%),
    var(--void);
}

.site-footer::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--lime) 18%, var(--cyan) 54%, transparent);
  opacity: 0.72;
}

.footer__grid {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(30px, 4vw, 56px);
  padding-bottom: clamp(30px, 4vw, 54px);
  border-bottom: 1px solid var(--grid);
}

.footer__brand { min-width: 0; }

.footer__mark {
  margin: 0;
  font-size: var(--fs-34);
  font-weight: 900;
  letter-spacing: -0.02em;
  line-height: 1.1;
  color: var(--bone);
}

.footer__sub {
  margin: 10px 0 0;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.2em;
  color: var(--lime);
}

.footer__title {
  margin: 0 0 16px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: 600;
  letter-spacing: 0.22em;
  color: var(--mist);
  text-transform: uppercase;
}

.footer__list { display: grid; gap: 10px; }

.footer__list a {
  display: inline-block;
  color: var(--bone);
  font-size: var(--fs-18);
  line-height: 1.5;
}

.footer__list a:hover { color: var(--lime); }

.footer__contact {
  max-width: var(--maxw);
  margin: clamp(26px, 3vw, 40px) auto 0;
  display: grid;
  gap: 10px;
}

.footer__cline {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin: 0;
  font-size: var(--fs-14);
}

.footer__key {
  flex: 0 0 62px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  color: var(--mist);
}

.footer__val {
  min-width: 0;
  font-family: var(--font-mono);
  font-size: var(--fs-14);
  color: var(--bone);
  word-break: break-word;
}

.footer__base {
  max-width: var(--maxw);
  margin: clamp(24px, 3vw, 38px) auto 0;
  display: flex;
  flex-wrap: wrap;
  gap: 12px 28px;
  align-items: baseline;
  justify-content: space-between;
}

.footer__closing {
  margin: 0;
  max-width: 46ch;
  font-size: var(--fs-14);
  color: var(--mist);
}

.footer__copy {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.12em;
  color: var(--mist);
}

/* 底部快捷胶囊 */
.quickbar {
  position: fixed;
  right: clamp(14px, 2.2vw, 30px);
  bottom: clamp(14px, 2.2vw, 30px);
  z-index: 80;
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px;
  border: 1px solid var(--grid);
  border-radius: 100px;
  background: rgba(7, 9, 15, 0.88);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  box-shadow: 0 18px 44px rgba(0, 0, 0, 0.55);
  opacity: 0;
  visibility: hidden;
  transform: translateY(14px);
  transition: opacity var(--t-mid), transform var(--t-mid), visibility var(--t-mid);
}

.quickbar[data-visible] {
  opacity: 1;
  visibility: visible;
  transform: none;
}

.quickbar__cta {
  padding: 9px 16px;
  border-radius: 100px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.12em;
  color: var(--mist);
  white-space: nowrap;
  transition: color var(--t-fast), background var(--t-fast);
}

.quickbar__cta:hover { color: var(--void); background: var(--lime); }

.quickbar__top {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--lime);
  color: var(--void);
  font-size: var(--fs-14);
  font-weight: 700;
  transition: background var(--t-fast), transform var(--t-fast);
}

.quickbar__top:hover { background: var(--cyan); transform: translateY(-2px); }

/* ---------- 5. 通用组件 ---------- */
.wrap {
  width: 100%;
  max-width: var(--maxw);
  margin-inline: auto;
}

.prose { max-width: 42em; }
.prose p { margin: 0 0 1.35em; }
.prose p:last-child { margin-bottom: 0; }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: 600;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--lime);
}

.eyebrow::before {
  content: "";
  width: 28px;
  height: 1px;
  background: currentColor;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 26px;
  border: 1px solid transparent;
  border-radius: 100px;
  font-family: var(--font-mono);
  font-size: var(--fs-14);
  font-weight: 600;
  letter-spacing: 0.08em;
  line-height: 1.4;
  transition: transform var(--t-fast), background var(--t-fast), color var(--t-fast), border-color var(--t-fast);
}

.btn--primary { background: var(--lime); color: var(--void); }
.btn--primary:hover { background: var(--cyan); color: var(--void); transform: translateY(-2px); }

.btn--ghost { border-color: var(--grid); color: var(--bone); }
.btn--ghost:hover { border-color: var(--lime); color: var(--lime); }

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.12em;
  color: var(--mist);
}

.breadcrumb li { display: inline-flex; align-items: center; }
.breadcrumb li + li::before { content: "/"; margin: 0 10px; color: var(--grid); }
.breadcrumb a { color: var(--mist); }
.breadcrumb a:hover { color: var(--lime); }
.breadcrumb [aria-current="page"] { color: var(--bone); }

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 11px;
  border: 1px solid var(--grid);
  border-radius: 100px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.14em;
  color: var(--mist);
}

.tag--lime { color: var(--lime); border-color: rgba(180, 255, 57, 0.42); }
.tag--amber { color: var(--amber); border-color: rgba(255, 145, 48, 0.42); }

.stat {
  font-family: var(--font-mono);
  font-weight: 600;
  line-height: 1;
  letter-spacing: -0.02em;
  font-variant-numeric: tabular-nums;
}

.stat--lg { font-size: var(--fs-56); }

.slab {
  position: relative;
  padding: clamp(28px, 4vw, 64px);
  border-radius: var(--radius-l);
  overflow: hidden;
}

.slab--jade { background: linear-gradient(158deg, rgba(6, 48, 44, 0.96), rgba(7, 9, 15, 0.92)); }
.slab--indigo { background: linear-gradient(158deg, rgba(36, 21, 66, 0.96), rgba(7, 9, 15, 0.92)); }
.slab--wine { background: linear-gradient(158deg, rgba(74, 15, 36, 0.96), rgba(7, 9, 15, 0.92)); }

.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(12px, 1.6vw, 24px);
}

.blueprint {
  background-image:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: clamp(36px, 5vw, 72px) clamp(36px, 5vw, 72px);
  background-position: center;
}

/* 响应式图片容器（页面阶段放入图片） */
.figure {
  position: relative;
  margin: 0;
  min-height: 120px;
  border: 1px solid var(--grid);
  border-radius: var(--radius-m);
  overflow: hidden;
  background: linear-gradient(145deg, var(--jade), var(--indigo) 52%, var(--wine));
}

.figure > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  aspect-ratio: 16 / 9;
}

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

.figure__cap {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 14px;
  padding: 16px 18px;
  background: linear-gradient(180deg, transparent, rgba(7, 9, 15, 0.94));
  font-size: var(--fs-14);
  color: var(--bone);
}

.figure__tag {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  color: var(--lime);
}

/* ---------- 6. 响应式 ---------- */
@media (min-width: 700px) {
  .topbar__coord { display: inline-block; }
  .nav-toggle { margin-left: 0; }
  .footer__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (min-width: 900px) {
  .topbar__status { display: flex; }
  .footer__contact { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px 48px; }
}

@media (min-width: 1024px) {
  .footer__grid { grid-template-columns: 1.8fr 1fr 1fr 0.9fr; }
}

@media (min-width: 1180px) {
  .rail:not([hidden]) { display: flex; }
  .navbar__meta { display: flex; }
  main { padding-left: 96px; }
}

@media (max-width: 1180px) {
  :root {
    --fs-260: 150px;
    --fs-96: 72px;
    --fs-56: 44px;
    --fs-34: 28px;
  }
}

@media (max-width: 900px) {
  html { scroll-padding-top: 112px; }
  [data-section] { scroll-margin-top: 112px; }

  .navbar {
    display: none;
    flex-direction: column;
    padding-bottom: 10px;
  }

  .navbar[data-open] { display: flex; }

  .navbar__list {
    flex-direction: column;
    width: 100%;
    border-left: 0;
  }

  .navbar__link {
    border-right: 0;
    border-bottom: 1px solid var(--grid);
    padding: 15px 4px;
    font-size: var(--fs-18);
  }

  .navbar__meta { display: flex; padding: 12px 4px 0; }
}

@media (max-width: 700px) {
  :root {
    --fs-260: 88px;
    --fs-96: 48px;
    --fs-56: 32px;
    --fs-34: 26px;
    --fs-22: 20px;
  }

  body { font-size: 17px; line-height: 1.85; }

  .brand__sub { letter-spacing: 0.12em; }
  .topbar__coord { display: none; }
  .footer__key { flex: 0 0 54px; }
  .quickbar { gap: 2px; padding: 5px; }
  .quickbar__cta { padding: 8px 12px; letter-spacing: 0.08em; }
  .quickbar__top { width: 34px; height: 34px; }
}

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

/* ---------- 7. 动效降级 ---------- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }

  html { scroll-behavior: auto; }
  body::before { background-attachment: initial; }
}