/*
  极速体育 站点样式表
  体育AI科技与App下载官网
  纯 CSS3，无远程字体、无远程资源；支持深色阅读模式与字号切换
*/

:root {
  --navy: #0b1f3a;
  --navy-2: #12294d;
  --navy-3: #182f57;
  --tech-blue: #1e6fd9;
  --tech-blue-light: #4d93ec;
  --teal: #14b8a6;
  --orange: #ff7a33;
  --purple: #7c5cfc;
  --warm-white: #faf8f5;
  --silver: #c7cdd6;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 22px;
  --shadow-sm: 0 2px 10px rgba(11, 31, 58, 0.06);
  --shadow-md: 0 10px 30px rgba(11, 31, 58, 0.1);
  --max-width: 1200px;
  --gradient-hero: linear-gradient(135deg, var(--navy) 0%, var(--navy-3) 45%, #234b8a 100%);
  --gradient-accent: linear-gradient(120deg, var(--tech-blue) 0%, var(--purple) 100%);
  --gradient-teal: linear-gradient(120deg, var(--teal) 0%, var(--tech-blue) 100%);

  /* 语义化配色（浅色默认） */
  --page-bg: var(--warm-white);
  --surface: #ffffff;
  --surface-alt: #edf0f4;
  --ink: #101826;
  --muted: #5b6472;
  --muted-2: #808a99;
  --line: #e4e8ee;
  --line-2: #edf0f4;

  font-size: 16px;
}

:root.fs-sm { font-size: 15px; }
:root.fs-lg { font-size: 18px; }

:root[data-theme="dark"] {
  --page-bg: #0a1220;
  --surface: #121b2c;
  --surface-alt: #182338;
  --ink: #e8edf7;
  --muted: #a3aec4;
  --muted-2: #8b96ac;
  --line: #263a53;
  --line-2: #1c2a40;
  --warm-white: #0a1220;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Microsoft YaHei", "PingFang SC", "Hiragino Sans GB", "Noto Sans CJK SC", "Segoe UI", Arial, sans-serif;
  color: var(--ink);
  background: var(--page-bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  transition: background-color 0.2s ease, color 0.2s ease;
}

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

a {
  color: var(--tech-blue);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

ul, ol {
  padding-left: 1.2em;
}

table {
  border-collapse: collapse;
  width: 100%;
}

h1, h2, h3, h4 {
  line-height: 1.35;
  color: var(--navy);
  margin: 0 0 0.6em;
}

:root[data-theme="dark"] h1,
:root[data-theme="dark"] h2,
:root[data-theme="dark"] h3,
:root[data-theme="dark"] h4 {
  color: #eef2fb;
}

h1 { font-size: 2rem; }
h2 { font-size: 1.55rem; }
h3 { font-size: 1.2rem; }
h4 { font-size: 1.05rem; }

p { margin: 0 0 1em; }

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

/* ---------- Skip link ---------- */
.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--navy);
  color: #fff;
  padding: 10px 16px;
  z-index: 999;
  border-radius: 0 0 8px 0;
}
.skip-link:focus {
  left: 0;
}

/* ---------- Top notice bar ---------- */
.top-bar {
  background: var(--navy);
  color: var(--silver);
  font-size: 0.82rem;
  padding: 6px 0;
}
.top-bar .container {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 6px;
}
.top-bar a { color: #cfe0ff; }

/* ---------- Header / Nav ---------- */
.site-header {
  background: var(--surface);
  border-bottom: 1px solid var(--line);
  position: sticky;
  top: 0;
  z-index: 100;
}

.nav-wrap {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 14px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
}

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

.logo-link img {
  width: 40px;
  height: 40px;
}

.logo-text {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
}

.logo-text strong {
  font-size: 1.25rem;
  color: var(--navy);
  letter-spacing: 0.5px;
}
:root[data-theme="dark"] .logo-text strong { color: #eef2fb; }

.logo-text span {
  font-size: 0.72rem;
  color: var(--muted-2);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  cursor: pointer;
}
.nav-toggle span {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--navy);
  margin: 0 auto;
}
:root[data-theme="dark"] .nav-toggle span { background: #eef2fb; }

.main-nav ul {
  list-style: none;
  display: flex;
  gap: 6px;
  margin: 0;
  padding: 0;
  flex-wrap: wrap;
}

.main-nav a {
  display: inline-block;
  padding: 9px 14px;
  border-radius: 999px;
  color: var(--navy);
  font-size: 0.95rem;
  font-weight: 600;
}
:root[data-theme="dark"] .main-nav a { color: #eef2fb; }

.main-nav a:hover,
.main-nav a:focus {
  background: var(--surface-alt);
  text-decoration: none;
}

.main-nav a.active {
  background: var(--gradient-accent);
  color: #fff;
}

.nav-cta {
  flex-shrink: 0;
}

/* ---------- Breadcrumb ---------- */
.breadcrumb-bar {
  background: var(--surface-alt);
  border-bottom: 1px solid var(--line);
}
.breadcrumb {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 10px 20px;
  font-size: 0.84rem;
  color: var(--muted);
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  align-items: center;
}
.breadcrumb a { color: var(--tech-blue); }
.breadcrumb .sep { color: var(--muted-2); }
.breadcrumb .current { color: var(--navy); font-weight: 600; }
:root[data-theme="dark"] .breadcrumb .current { color: #eef2fb; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 11px 22px;
  border-radius: 999px;
  font-weight: 700;
  font-size: 0.95rem;
  border: 2px solid transparent;
  cursor: pointer;
  font-family: inherit;
}
.btn:hover { text-decoration: none; }

.btn-primary {
  background: var(--gradient-accent);
  color: #fff;
  box-shadow: var(--shadow-sm);
}
.btn-primary:hover { filter: brightness(1.06); }

.btn-secondary {
  background: var(--surface);
  color: var(--navy);
  border-color: var(--line);
}
:root[data-theme="dark"] .btn-secondary { color: #eef2fb; }
.btn-secondary:hover { border-color: var(--tech-blue); color: var(--tech-blue); }

.btn-ghost {
  background: transparent;
  color: #fff;
  border-color: rgba(255,255,255,0.55);
}
.btn-ghost:hover { border-color: #fff; }

.btn-orange {
  background: linear-gradient(120deg, var(--orange), #ff9a5c);
  color: #fff;
}

.btn-sm { padding: 7px 14px; font-size: 0.82rem; }
.btn-block { width: 100%; justify-content: center; }

.demo-btn.active {
  background: linear-gradient(120deg, var(--orange), #ffb066);
  color: #fff;
  border-color: transparent;
}

/* ---------- Hero ---------- */
.hero {
  background: var(--gradient-hero);
  color: #fff;
  position: relative;
  overflow: hidden;
}
.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 85% 20%, rgba(124,92,252,0.35), transparent 55%),
              radial-gradient(circle at 10% 90%, rgba(20,184,166,0.25), transparent 45%);
  pointer-events: none;
}
.hero-grid {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 56px 20px 64px;
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 40px;
  align-items: center;
  position: relative;
}
.eyebrow {
  display: inline-block;
  font-size: 0.8rem;
  letter-spacing: 1px;
  background: rgba(255,255,255,0.14);
  color: #cfe0ff;
  padding: 5px 12px;
  border-radius: 999px;
  margin-bottom: 14px;
  font-weight: 600;
}
.hero h1 {
  color: #fff;
  font-size: 2.15rem;
  margin-bottom: 16px;
}
.hero-lead {
  color: #e4ecfb;
  font-size: 1.02rem;
  max-width: 560px;
}
.hero-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-top: 22px;
}
.hero-stats {
  display: flex;
  gap: 26px;
  margin-top: 30px;
  flex-wrap: wrap;
}
.hero-stats div strong {
  display: block;
  font-size: 1.3rem;
  color: #fff;
}
.hero-stats div span {
  font-size: 0.8rem;
  color: #b9c8e6;
}
.hero-image {
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.16);
  border-radius: var(--radius-lg);
  padding: 18px;
}

.page-hero {
  background: var(--gradient-hero);
  color: #fff;
  padding: 40px 0 46px;
  position: relative;
  overflow: hidden;
}
.page-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 90% 10%, rgba(20,184,166,0.3), transparent 50%);
}
.page-hero .container { position: relative; }
.page-hero h1 { color: #fff; font-size: 1.85rem; margin-bottom: 10px; }
.page-hero p { color: #dce6fa; max-width: 720px; margin-bottom: 0; }

/* ---------- Sections ---------- */
.section {
  padding: 56px 0;
}
.section-alt {
  background: var(--surface);
}
.section-tint {
  background: var(--surface-alt);
}
.section-head {
  max-width: 720px;
  margin: 0 auto 32px;
  text-align: left;
}
.section-head.center { text-align: center; margin-left: auto; margin-right: auto; }
.section-head h2 { margin-bottom: 10px; }
.section-head p { color: var(--muted); margin-bottom: 0; }

.section-foot-link {
  margin-top: 26px;
}

/* ---------- Grids ---------- */
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }

.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: center;
}
.split.reverse .split-image { order: 2; }
.split.reverse .split-text { order: 1; }

/* ---------- Cards ---------- */
.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 22px;
}

/* Module / feature card (AI modules, app features) */
.card-feature {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 22px;
  border-top: 3px solid var(--tech-blue);
}
.card-feature:nth-child(3n+2) { border-top-color: var(--teal); }
.card-feature:nth-child(3n+3) { border-top-color: var(--orange); }
.card-feature .icon-num {
  width: 34px;
  height: 34px;
  border-radius: 10px;
  background: var(--surface-alt);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  color: var(--tech-blue);
  margin-bottom: 12px;
}
.card-feature h3 { font-size: 1.02rem; margin-bottom: 6px; }
.card-feature p { color: var(--muted); font-size: 0.88rem; margin-bottom: 0; }

/* Device card (devices.html) */
.card-device {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
}
.card-device-media {
  background: var(--navy);
  padding: 16px;
}
.card-device-body { padding: 18px 20px 22px; flex: 1; display: flex; flex-direction: column; }
.card-device-name { font-size: 1.1rem; color: var(--navy); font-weight: 800; margin: 0 0 4px; }
:root[data-theme="dark"] .card-device-name { color: #eef2fb; }
.card-device-meta { color: var(--muted); font-size: 0.85rem; margin-bottom: 10px; }
.card-device-fields {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 4px 10px;
  font-size: 0.82rem;
  color: var(--muted);
  margin-bottom: 12px;
}
.card-device-fields dt { font-weight: 700; color: var(--navy); }
:root[data-theme="dark"] .card-device-fields dt { color: #cfe0ff; }
.card-device-fields dd { margin: 0; }
.card-device-tags { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 12px; }
.card-device-note {
  background: var(--surface-alt);
  border-radius: var(--radius-sm);
  padding: 10px 12px;
  font-size: 0.82rem;
  color: var(--muted);
  margin-top: auto;
}

.tag {
  display: inline-block;
  font-size: 0.72rem;
  padding: 3px 10px;
  border-radius: 999px;
  background: var(--surface-alt);
  color: var(--navy);
  font-weight: 700;
  border: 1px solid var(--line);
}
:root[data-theme="dark"] .tag { color: #cfe0ff; }
.tag-sport { background: rgba(30,111,217,0.1); color: var(--tech-blue); border-color: rgba(30,111,217,0.25); }
.tag-device { background: rgba(20,184,166,0.1); color: #0d8b7d; border-color: rgba(20,184,166,0.25); }
.tag-ai { background: rgba(124,92,252,0.12); color: var(--purple); border-color: rgba(124,92,252,0.28); }

.status-badge {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-size: 0.72rem;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: 999px;
}
.status-official { background: rgba(20,184,166,0.14); color: #0d8b7d; }
.status-media { background: rgba(30,111,217,0.12); color: var(--tech-blue); }
.status-demo { background: rgba(255,122,51,0.14); color: #c85a1c; }
.status-analysis { background: rgba(124,92,252,0.13); color: var(--purple); }

/* Article preview card (index.html) */
.card-article {
  display: flex;
  flex-direction: column;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  overflow: hidden;
  background: var(--surface);
  box-shadow: var(--shadow-sm);
}
.card-article-media { position: relative; }
.card-article-cat {
  position: absolute;
  top: 12px;
  left: 12px;
  background: rgba(11,31,58,0.82);
  color: #fff;
  font-size: 0.72rem;
  padding: 4px 10px;
  border-radius: 999px;
  font-weight: 700;
}
.card-article-body { padding: 18px 20px 20px; display: flex; flex-direction: column; flex: 1; }
.card-article-date { font-size: 0.78rem; color: var(--muted-2); margin-bottom: 6px; }
.card-article-body h3 { font-size: 1.05rem; margin-bottom: 8px; }
.card-article-body p { color: var(--muted); font-size: 0.88rem; flex: 1; }
.card-article-more { font-weight: 700; font-size: 0.86rem; }

/* Download entry card */
.card-download {
  background: var(--navy);
  color: #fff;
  border-radius: var(--radius-lg);
  padding: 26px;
  position: relative;
  overflow: hidden;
}
.card-download h3 { color: #fff; }
.card-download p { color: #cfd9ec; font-size: 0.9rem; }
.card-download ul { color: #cfd9ec; font-size: 0.85rem; padding-left: 1.1em; }
.card-download .btn-primary { margin-top: 10px; }

.card-info {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 24px;
}

/* ---------- Filter bar ---------- */
.filter-bar {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 26px;
}
.filter-btn {
  padding: 8px 16px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--navy);
  font-size: 0.86rem;
  font-weight: 600;
  cursor: pointer;
  font-family: inherit;
}
:root[data-theme="dark"] .filter-btn { color: #eef2fb; }
.filter-btn:hover { border-color: var(--tech-blue); }
.filter-btn.active {
  background: var(--gradient-accent);
  color: #fff;
  border-color: transparent;
}
[data-filter-target] [hidden] { display: none; }

/* ---------- Timeline ---------- */
.timeline {
  position: relative;
  margin: 0;
  padding: 0;
  list-style: none;
  border-left: 2px solid var(--line);
  margin-left: 8px;
}
.timeline-item {
  position: relative;
  padding: 0 0 26px 26px;
}
.timeline-item:last-child { padding-bottom: 0; }
.timeline-dot {
  position: absolute;
  left: -7px;
  top: 3px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--tech-blue);
  border: 2px solid var(--surface);
  box-shadow: 0 0 0 2px var(--tech-blue);
}
.timeline-date { font-size: 0.78rem; color: var(--muted-2); font-weight: 700; }
.timeline-content h4 { margin: 2px 0 4px; font-size: 0.98rem; }
.timeline-content p { margin: 0; color: var(--muted); font-size: 0.86rem; }

/* ---------- Table ---------- */
.table-scroll {
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--surface);
}
table.data-table {
  min-width: 720px;
  font-size: 0.88rem;
}
table.data-table th,
table.data-table td {
  padding: 12px 14px;
  border-bottom: 1px solid var(--line-2);
  text-align: left;
  vertical-align: top;
}
table.data-table thead th {
  background: var(--navy);
  color: #fff;
  font-weight: 700;
  white-space: nowrap;
}
table.data-table tbody tr:hover { background: var(--surface-alt); }
table.data-table tbody tr:last-child td { border-bottom: none; }
table.data-table td.num, table.data-table th.num { text-align: right; }

.board-toolbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  margin-bottom: 14px;
  flex-wrap: wrap;
}
.board-toggle-btn {
  border: 1px solid var(--line);
  background: var(--surface);
  border-radius: 999px;
  padding: 7px 14px;
  font-size: 0.82rem;
  cursor: pointer;
  font-weight: 600;
  color: var(--navy);
  font-family: inherit;
}
:root[data-theme="dark"] .board-toggle-btn { color: #eef2fb; }
.board-toggle-btn[aria-pressed="true"] {
  background: rgba(20,184,166,0.14);
  border-color: var(--teal);
  color: #0d8b7d;
}
.board-select {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 6px 10px;
  font-size: 0.82rem;
  color: var(--navy);
  cursor: pointer;
  background: var(--surface);
  font-family: inherit;
}
:root[data-theme="dark"] .board-select { color: #eef2fb; }

.notice-box {
  background: #fff7ec;
  border: 1px solid #f2ddb8;
  border-radius: var(--radius-md);
  padding: 14px 18px;
  font-size: 0.85rem;
  color: #7a5417;
  margin: 18px 0;
}
.notice-box strong { color: #5c3d0e; }
.notice-box.blue {
  background: #eef4ff;
  border-color: #c9dcff;
  color: #1c3f73;
}
.notice-box.blue strong { color: var(--navy); }
.notice-box.teal {
  background: #eafbf8;
  border-color: #b9ece4;
  color: #0d5c52;
}
:root[data-theme="dark"] .notice-box { background: #2a230f; border-color: #4a3c18; color: #f0d9a3; }
:root[data-theme="dark"] .notice-box strong { color: #ffe6b3; }
:root[data-theme="dark"] .notice-box.blue { background: #10203a; border-color: #234a7c; color: #cfe0ff; }
:root[data-theme="dark"] .notice-box.teal { background: #0d2622; border-color: #1c5148; color: #bdf2e8; }

/* ---------- FAQ ---------- */
.faq-list { max-width: 860px; }
.faq-item {
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  margin-bottom: 12px;
  background: var(--surface);
  overflow: hidden;
}
.faq-item summary {
  cursor: pointer;
  list-style: none;
  padding: 16px 46px 16px 20px;
  font-weight: 700;
  color: var(--navy);
  position: relative;
  font-size: 0.98rem;
}
:root[data-theme="dark"] .faq-item summary { color: #eef2fb; }
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
  content: "+";
  position: absolute;
  right: 18px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 1.3rem;
  color: var(--tech-blue);
  font-weight: 400;
}
.faq-item[open] summary::after { content: "\2212"; }
.faq-item[open] summary { border-bottom: 1px solid var(--line-2); }
.faq-answer {
  padding: 14px 20px 20px;
  color: var(--muted);
  font-size: 0.9rem;
}

/* ---------- Figures ---------- */
.article-figure {
  margin: 0 0 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  overflow: hidden;
  background: var(--surface);
}
.article-figure img { width: 100%; }
.article-figure figcaption {
  padding: 12px 16px;
  font-size: 0.82rem;
  color: var(--muted);
  border-top: 1px solid var(--line-2);
  background: var(--surface-alt);
}

/* ---------- Article ---------- */
.article-block {
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: var(--surface);
  padding: 30px 30px 34px;
  margin-bottom: 34px;
  box-shadow: var(--shadow-sm);
  scroll-margin-top: 90px;
}
.article-meta-row {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  align-items: center;
  margin-bottom: 14px;
  font-size: 0.8rem;
  color: var(--muted-2);
}
.article-block h2 { font-size: 1.35rem; }
.article-summary {
  background: var(--surface-alt);
  border-left: 3px solid var(--tech-blue);
  padding: 12px 16px;
  border-radius: 0 8px 8px 0;
  color: var(--navy);
  font-size: 0.92rem;
  margin-bottom: 20px;
}
:root[data-theme="dark"] .article-summary { color: #eef2fb; }
.article-body p { color: var(--ink); }
.article-footer-meta {
  margin-top: 20px;
  padding-top: 16px;
  border-top: 1px dashed var(--line);
  font-size: 0.78rem;
  color: var(--muted-2);
  line-height: 1.9;
}
.article-links {
  margin-top: 14px;
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
  font-size: 0.86rem;
  font-weight: 700;
}

.article-index {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
  list-style: none;
  padding: 0;
  margin: 0 0 40px;
}
.article-index li a {
  display: block;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  color: var(--navy);
  font-size: 0.88rem;
  font-weight: 600;
}
:root[data-theme="dark"] .article-index li a { color: #eef2fb; }
.article-index li a:hover { border-color: var(--tech-blue); text-decoration: none; }
.article-index .idx-num {
  color: var(--tech-blue);
  font-weight: 800;
  margin-right: 6px;
}

.short-article {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 22px 24px;
}
.short-article h3 { font-size: 1.05rem; }
.short-article p { color: var(--muted); font-size: 0.92rem; margin-bottom: 0.8em; }
.short-article .article-footer-meta { margin-top: 12px; padding-top: 12px; }

/* ---------- AI demo ---------- */
.ai-demo {
  background: var(--navy);
  border-radius: var(--radius-lg);
  padding: 28px;
  color: #fff;
}
.ai-demo h3 { color: #fff; }
.ai-demo-form {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
  margin-bottom: 18px;
}
.ai-demo-field { display: flex; flex-direction: column; gap: 6px; }
.ai-demo-field label { font-size: 0.8rem; color: #b9c8e6; font-weight: 700; }
.ai-demo-field select {
  padding: 9px 10px;
  border-radius: 8px;
  border: 1px solid rgba(255,255,255,0.25);
  background: rgba(255,255,255,0.08);
  color: #fff;
  font-size: 0.88rem;
  font-family: inherit;
}
.ai-demo-field select option { color: #101826; }
.ai-demo-check {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  color: #dce6fa;
}
.ai-demo-checks {
  display: flex;
  gap: 18px;
  flex-wrap: wrap;
  margin-bottom: 18px;
}
.ai-demo-output {
  background: rgba(255,255,255,0.07);
  border: 1px solid rgba(255,255,255,0.18);
  border-radius: var(--radius-md);
  padding: 18px 20px;
  font-size: 0.88rem;
  color: #eef2fb;
  min-height: 110px;
}
.ai-demo-output h4 { color: #fff; font-size: 0.95rem; }
.ai-demo-output .tag { background: rgba(255,255,255,0.14); color: #fff; border-color: rgba(255,255,255,0.3); }

/* ---------- Login demo ---------- */
.login-demo-panel {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 28px;
  max-width: 460px;
}
.login-demo-panel h3 { margin-bottom: 6px; }
.login-demo label {
  display: block;
  font-size: 0.84rem;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 16px;
}
:root[data-theme="dark"] .login-demo label { color: #eef2fb; }
.login-demo input[type="text"] {
  display: block;
  width: 100%;
  margin-top: 6px;
  padding: 10px 12px;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: var(--surface-alt);
  color: var(--muted);
  font-size: 0.92rem;
  font-family: inherit;
}
.login-demo-status {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.86rem;
  font-weight: 700;
  padding: 8px 14px;
  border-radius: 999px;
  background: var(--surface-alt);
  color: var(--muted);
  margin-bottom: 16px;
}
.login-demo-status.connected {
  background: rgba(20,184,166,0.14);
  color: #0d8b7d;
}
.login-demo-status .dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--muted-2);
}
.login-demo-status.connected .dot { background: #0d8b7d; }

/* ---------- Reading preference (dark mode / font size) ---------- */
.pref-panel {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 26px;
}
.pref-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 14px 0;
  border-bottom: 1px solid var(--line-2);
  flex-wrap: wrap;
}
.pref-row:last-child { border-bottom: none; }
.pref-row-label strong { display: block; color: var(--navy); font-size: 0.96rem; }
:root[data-theme="dark"] .pref-row-label strong { color: #eef2fb; }
.pref-row-label span { color: var(--muted); font-size: 0.82rem; }
.pref-toggle-group {
  display: flex;
  gap: 6px;
  background: var(--surface-alt);
  padding: 4px;
  border-radius: 999px;
}
.pref-toggle-group button {
  border: none;
  background: transparent;
  padding: 7px 14px;
  border-radius: 999px;
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--muted);
  cursor: pointer;
  font-family: inherit;
}
.pref-toggle-group button.active {
  background: var(--surface);
  color: var(--tech-blue);
  box-shadow: var(--shadow-sm);
}

/* ---------- Device / compare tables ---------- */
.compat-icon { font-weight: 800; }
.ok-yes { color: #0d8b7d; }
.ok-no { color: #c0392b; }
.ok-partial { color: #b9770e; }

/* ---------- Steps ---------- */
.steps {
  counter-reset: step;
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 14px;
}
.steps li {
  counter-increment: step;
  position: relative;
  padding-left: 46px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding-top: 12px;
  padding-bottom: 12px;
  padding-right: 14px;
}
.steps li::before {
  content: counter(step);
  position: absolute;
  left: 12px;
  top: 12px;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--gradient-accent);
  color: #fff;
  font-size: 0.8rem;
  font-weight: 800;
  display: flex;
  align-items: center;
  justify-content: center;
}
.steps strong { color: var(--navy); }
:root[data-theme="dark"] .steps strong { color: #eef2fb; }

.company-table th { width: 160px; background: var(--surface-alt); color: var(--navy); }
:root[data-theme="dark"] .company-table th { color: #eef2fb; }

/* ---------- Footer ---------- */
.site-footer {
  background: var(--navy);
  color: #b9c8e6;
  padding: 46px 0 20px;
  font-size: 0.86rem;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
  gap: 30px;
  padding-bottom: 30px;
  border-bottom: 1px solid rgba(255,255,255,0.12);
}
.footer-col h4 {
  color: #fff;
  font-size: 0.92rem;
  margin-bottom: 14px;
}
.footer-col ul { list-style: none; padding: 0; margin: 0; }
.footer-col li { margin-bottom: 9px; }
.footer-col a { color: #b9c8e6; }
.footer-col a:hover { color: #fff; }
.footer-brand-logo { display: flex; align-items: center; gap: 10px; margin-bottom: 12px; }
.footer-brand-logo img { width: 34px; height: 34px; }
.footer-brand-logo strong { color: #fff; font-size: 1.1rem; }
.footer-desc { color: #a8b8d8; font-size: 0.84rem; }
.footer-bottom {
  padding-top: 20px;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px;
  font-size: 0.78rem;
  color: #93a3c4;
}

/* ---------- Back to top ---------- */
.back-to-top {
  position: fixed;
  right: 22px;
  bottom: 22px;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background: var(--navy);
  color: #fff;
  border: none;
  cursor: pointer;
  font-size: 1.1rem;
  box-shadow: var(--shadow-md);
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 90;
}
.back-to-top.show { display: flex; }

/* ---------- Utility ---------- */
.mt-0 { margin-top: 0; }
.mb-0 { margin-bottom: 0; }
.text-muted { color: var(--muted); }
.text-center { text-align: center; }
.small-note { font-size: 0.78rem; color: var(--muted-2); }

/* ---------- Responsive ---------- */
@media (max-width: 980px) {
  .hero-grid { grid-template-columns: 1fr; }
  .split { grid-template-columns: 1fr; }
  .split.reverse .split-image,
  .split.reverse .split-text { order: initial; }
  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .ai-demo-form { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 720px) {
  .nav-toggle { display: flex; }
  .main-nav {
    display: none;
    width: 100%;
    order: 3;
  }
  .main-nav.open { display: block; }
  .main-nav ul { flex-direction: column; gap: 2px; }
  .main-nav a { display: block; }
  .nav-wrap { flex-wrap: wrap; }
  .nav-cta { order: 2; margin-left: auto; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .hero h1 { font-size: 1.6rem; }
  .page-hero h1 { font-size: 1.4rem; }
  .article-index { grid-template-columns: 1fr; }
  .ai-demo-form { grid-template-columns: 1fr; }
  .article-block { padding: 22px 18px 26px; }
  .pref-row { flex-direction: column; align-items: flex-start; }
  h1 { font-size: 1.6rem; }
  h2 { font-size: 1.3rem; }
}