/* ==========================================================================
   百家乐官网 - style.css
   上海百家乐ai大模型公司
   静态站点全局样式，无任何第三方框架依赖
   ========================================================================== */

:root {
  --bg: #f7f5f0;
  --bg-alt: #efeae1;
  --bg-deep: #eee9e0;
  --surface: #ffffff;
  --surface-soft: #fbf9f5;
  --line: #e2ddd2;
  --line-strong: #cfc8ba;

  --ink: #2b2e33;
  --ink-soft: #565c64;
  --ink-faint: #83898f;

  --mist: #5c7a99;
  --mist-deep: #3f5b78;
  --cyan: #1aa3ad;
  --cyan-deep: #10767e;
  --orange: #d98b46;
  --orange-deep: #b96f30;
  --green: #5f9d74;
  --green-deep: #497b5a;

  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;

  --shadow-sm: 0 1px 3px rgba(43, 46, 51, 0.06);
  --shadow-md: 0 6px 20px rgba(43, 46, 51, 0.08);
  --shadow-lg: 0 16px 40px rgba(43, 46, 51, 0.12);

  --maxw: 1160px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font);
  background: var(--bg);
  color: var(--ink);
  line-height: 1.75;
  font-size: 16px;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}
img, svg { max-width: 100%; display: block; }
a { color: var(--cyan-deep); text-decoration: none; }
a:hover { text-decoration: underline; }
ul, ol { padding-left: 1.3em; }
h1, h2, h3, h4 { color: var(--ink); line-height: 1.35; margin: 0 0 0.6em; font-weight: 700; }
p { margin: 0 0 1em; }

.container { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }
.section { padding: 64px 0; }
.section-alt { background: var(--bg-alt); }
.section-tight { padding: 40px 0; }

.eyebrow {
  display: inline-block;
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--cyan-deep);
  background: rgba(26, 163, 173, 0.1);
  padding: 4px 12px;
  border-radius: 999px;
  margin-bottom: 14px;
  font-weight: 600;
}

.section-head { max-width: 760px; margin: 0 0 36px; }
.section-head h2 { font-size: 30px; }
.section-head p { color: var(--ink-soft); font-size: 16px; }

/* ---------------- Header / Nav ---------------- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(247, 245, 240, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.site-header .container { display: flex; align-items: center; justify-content: space-between; height: 72px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 19px; color: var(--ink); }
.brand:hover { text-decoration: none; }
.brand img { width: 34px; height: 34px; }
.brand .brand-sub { display: block; font-size: 11px; font-weight: 400; color: var(--ink-faint); }

.main-nav { display: flex; gap: 4px; align-items: center; }
.main-nav a {
  color: var(--ink-soft); font-size: 14.5px; font-weight: 600;
  padding: 9px 13px; border-radius: 999px; white-space: nowrap;
}
.main-nav a:hover, .main-nav a.active { background: var(--ink); color: #fff; text-decoration: none; }

.nav-toggle {
  display: none; width: 40px; height: 40px; border-radius: 10px; border: 1px solid var(--line-strong);
  background: var(--surface); cursor: pointer; align-items: center; justify-content: center;
}
.nav-toggle span, .nav-toggle::before, .nav-toggle::after { display: none; }
.nav-toggle svg { width: 20px; height: 20px; }

/* ---------------- Hero ---------------- */
.hero { padding: 60px 0 48px; }
.hero .container { display: grid; grid-template-columns: 1.1fr 0.9fr; gap: 48px; align-items: center; }
.hero h1 { font-size: 38px; letter-spacing: -0.01em; }
.hero .lede { font-size: 18px; color: var(--ink-soft); }
.hero .sub { font-size: 15px; color: var(--ink-faint); }
.hero-art { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-lg); padding: 18px; box-shadow: var(--shadow-md); display: flex; justify-content: center; }
.hero-art img { max-width: 260px; width: 100%; height: auto; margin: 0 auto; }
.hero-tags { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 20px; }
.hero-tags span { font-size: 13px; background: var(--surface); border: 1px solid var(--line-strong); padding: 5px 11px; border-radius: 999px; color: var(--ink-soft); }

.page-hero { padding: 44px 0 8px; }
.page-hero .eyebrow { margin-bottom: 10px; }
.page-hero h1 { font-size: 32px; max-width: 820px; }
.page-hero .lede { font-size: 16.5px; color: var(--ink-soft); max-width: 760px; }
.breadcrumb { font-size: 13px; color: var(--ink-faint); margin-bottom: 10px; }
.breadcrumb a { color: var(--ink-faint); }
.breadcrumb .sep { margin: 0 6px; }

/* ---------------- Buttons ---------------- */
.btn {
  display: inline-flex; align-items: center; gap: 8px; font-weight: 700; font-size: 14.5px;
  padding: 12px 22px; border-radius: 999px; border: 1px solid transparent; cursor: pointer;
}
.btn:hover { text-decoration: none; }
.btn-primary { background: var(--ink); color: #fff; }
.btn-primary:hover { background: var(--mist-deep); }
.btn-ghost { background: transparent; border-color: var(--line-strong); color: var(--ink); }
.btn-ghost:hover { background: var(--surface); }
.btn-row { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 24px; }

/* ---------------- Cards / Grid ---------------- */
.grid { display: grid; gap: 20px; }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }

.card {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-md);
  padding: 22px; box-shadow: var(--shadow-sm);
}
.card h3 { font-size: 17px; margin-bottom: 8px; }
.card p { color: var(--ink-soft); font-size: 14.5px; margin-bottom: 0; }
.card .tag { font-size: 12px; color: var(--cyan-deep); font-weight: 700; margin-bottom: 8px; display: block; }

/* ---------------- Long-form Articles ---------------- */
.article-list { display: flex; flex-direction: column; gap: 44px; }
.article {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-lg);
  padding: 36px clamp(20px, 4vw, 44px);
}
.article .tag { display: inline-block; font-size: 12.5px; font-weight: 700; color: var(--cyan-deep);
  background: rgba(26,163,173,0.09); padding: 4px 11px; border-radius: 999px; margin-bottom: 12px; }
.article h2, .article h3.article-title { font-size: 24px; margin-bottom: 16px; line-height: 1.45; }
.article p { color: var(--ink-soft); font-size: 15.5px; }
.article p strong { color: var(--ink); }
.article .note {
  background: var(--bg-alt); border-left: 3px solid var(--orange); padding: 10px 16px; border-radius: 6px;
  font-size: 14px; color: var(--ink-soft); margin: 18px 0;
}
.article .sim-box {
  background: var(--surface-soft); border: 1px dashed var(--line-strong); border-radius: var(--radius-sm);
  padding: 14px 18px; font-size: 14px; color: var(--ink-soft); margin: 16px 0; font-family: "SFMono-Regular", Consolas, Menlo, monospace;
}
.article .links-out { font-size: 14.5px; margin-top: 18px; padding-top: 16px; border-top: 1px dashed var(--line); }
.article .links-out a { font-weight: 700; margin-right: 18px; }

.observe-list { display: flex; flex-direction: column; gap: 22px; }
.observe { background: var(--bg-alt); border-radius: var(--radius-md); padding: 22px 26px; }
.observe h3 { font-size: 18px; }
.observe p { color: var(--ink-soft); font-size: 14.5px; margin-bottom: 0; }

/* ---------------- Summary /回流 cards ---------------- */
.summary-card { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-md); padding: 20px 22px; }
.summary-card .cat { font-size: 12px; font-weight: 700; color: var(--ink-faint); text-transform: uppercase; letter-spacing: 0.03em; margin-bottom: 6px; display:block; }
.summary-card h3 { font-size: 16.5px; margin-bottom: 8px; }
.summary-card p { font-size: 14px; color: var(--ink-soft); }
.summary-card a.more { font-size: 13.5px; font-weight: 700; }

/* ---------------- Diagram frame ---------------- */
.diagram { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-lg); padding: 20px; box-shadow: var(--shadow-sm); overflow-x: auto; text-align: center; }
.diagram img.diagram-compact { max-width: 480px; margin: 0 auto; }
.diagram figcaption { font-size: 13px; color: var(--ink-faint); margin-top: 10px; text-align: center; }
.diagram-row { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }

/* ---------------- FAQ ---------------- */
.faq-list { display: flex; flex-direction: column; gap: 10px; }
.faq-item { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-md); overflow: hidden; }
.faq-q {
  width: 100%; text-align: left; background: none; border: none; cursor: pointer; padding: 16px 20px;
  font-size: 15px; font-weight: 700; color: var(--ink); display: flex; justify-content: space-between; align-items: center; gap: 12px;
}
.faq-q::after { content: "+"; font-size: 20px; color: var(--ink-faint); flex-shrink: 0; }
.faq-item.open .faq-q::after { content: "−"; }
.faq-a { max-height: 0; overflow: hidden; transition: max-height 0.25s ease; padding: 0 20px; }
.faq-item.open .faq-a { max-height: 600px; padding: 0 20px 18px; }
.faq-a p { color: var(--ink-soft); font-size: 14.5px; margin: 0; }
.faq-cols { columns: 1; }

/* ---------------- Tabs / interactive demo blocks ---------------- */
.demo-box { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-lg); padding: 24px; box-shadow: var(--shadow-sm); }
.tab-bar { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 18px; }
.tab-btn { padding: 8px 16px; border-radius: 999px; border: 1px solid var(--line-strong); background: var(--surface); font-size: 13.5px; font-weight: 700; cursor: pointer; color: var(--ink-soft); }
.tab-btn.active { background: var(--ink); color: #fff; border-color: var(--ink); }
.tab-panel { display: none; }
.tab-panel.active { display: block; }

.stat-row { display: grid; grid-template-columns: repeat(auto-fit, minmax(120px, 1fr)); gap: 12px; margin: 16px 0; }
.stat-tile { background: var(--bg-alt); border-radius: var(--radius-sm); padding: 12px 14px; }
.stat-tile .k { font-size: 12px; color: var(--ink-faint); display: block; margin-bottom: 4px; }
.stat-tile .v { font-size: 18px; font-weight: 700; }
.stat-tile .v.medium { color: var(--orange-deep); }
.stat-tile .v.ok { color: var(--green-deep); }
.stat-tile .v.warn { color: var(--orange-deep); }

.timeline { display: flex; flex-direction: column; gap: 0; border-left: 2px solid var(--line-strong); margin-left: 8px; }
.timeline-step { position: relative; padding: 0 0 26px 22px; }
.timeline-step::before { content: ""; position: absolute; left: -7px; top: 2px; width: 12px; height: 12px; border-radius: 50%; background: var(--cyan); border: 2px solid var(--surface); }
.timeline-step .t { font-size: 12.5px; color: var(--ink-faint); font-weight: 700; }
.timeline-step h4 { font-size: 15.5px; margin: 4px 0 4px; }
.timeline-step p { font-size: 13.5px; color: var(--ink-soft); margin: 0; }

.scenario-toggle { display: flex; gap: 10px; margin-bottom: 18px; flex-wrap: wrap; }
.scenario-panel { display: none; background: var(--bg-alt); border-radius: var(--radius-md); padding: 18px 20px; }
.scenario-panel.active { display: block; }

.topology { display: flex; flex-wrap: wrap; gap: 14px; }
.topology .node { flex: 1 1 220px; background: var(--bg-alt); border-radius: var(--radius-md); padding: 16px 18px; border: 1px solid var(--line); }
.topology .node h4 { font-size: 14.5px; margin-bottom: 6px; }
.topology .node .cap { font-size: 12.5px; color: var(--ink-faint); }
.topology .node .cap span { display: inline-block; background: var(--surface); border: 1px solid var(--line-strong); border-radius: 999px; padding: 2px 8px; margin: 3px 4px 0 0; }

.plan-steps { display: flex; flex-direction: column; gap: 10px; }
.plan-step { display: flex; gap: 12px; align-items: flex-start; background: var(--bg-alt); border-radius: var(--radius-sm); padding: 12px 16px; }
.plan-step .idx { flex-shrink: 0; width: 26px; height: 26px; border-radius: 50%; background: var(--ink); color: #fff; font-size: 12.5px; font-weight: 700; display: flex; align-items: center; justify-content: center; }
.plan-step.ask { border: 1px dashed var(--orange); background: rgba(217,139,70,0.08); }
.plan-step .label { font-size: 14px; }
.plan-step .label b { display: block; }
.plan-step .label span { font-size: 12.5px; color: var(--ink-faint); }

.chat-demo { display: flex; flex-direction: column; gap: 10px; }
.bubble { max-width: 78%; padding: 10px 15px; border-radius: 14px; font-size: 14px; }
.bubble.user { align-self: flex-end; background: var(--ink); color: #fff; border-bottom-right-radius: 4px; }
.bubble.ai { align-self: flex-start; background: var(--bg-alt); border-bottom-left-radius: 4px; }
.bubble.side { align-self: flex-start; background: transparent; border: 1px dashed var(--line-strong); color: var(--ink-faint); font-style: italic; }
.confidence-tag { font-size: 11.5px; margin-top: 4px; color: var(--ink-faint); }

.app-mock { display: grid; grid-template-columns: repeat(4, 1fr); gap: 10px; }
.app-tile { background: var(--bg-alt); border-radius: var(--radius-sm); padding: 14px; text-align: center; }
.app-tile .icon { width: 30px; height: 30px; margin: 0 auto 8px; }
.app-tile .name { font-size: 12px; color: var(--ink-faint); }
.app-tile .val { font-size: 14.5px; font-weight: 700; }

/* ---------------- About / Company ---------------- */
.about-box { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-lg); padding: 30px 34px; }
.about-box p { color: var(--ink-soft); font-size: 15px; }
.about-meta { display: flex; gap: 26px; flex-wrap: wrap; margin-top: 16px; font-size: 13.5px; color: var(--ink-faint); }
.about-meta b { color: var(--ink); }

/* ---------------- Footer ---------------- */
.site-footer { background: var(--ink); color: rgba(255,255,255,0.72); padding: 48px 0 26px; margin-top: 60px; }
.footer-grid { display: grid; grid-template-columns: 1.4fr repeat(4, 1fr); gap: 26px; }
.footer-grid h4 { color: #fff; font-size: 14px; margin-bottom: 12px; }
.footer-grid a { color: rgba(255,255,255,0.68); font-size: 13.5px; display: block; margin-bottom: 8px; }
.footer-grid a:hover { color: #fff; }
.footer-brand { font-weight: 700; color: #fff; font-size: 18px; margin-bottom: 8px; }
.footer-desc { font-size: 13px; line-height: 1.7; max-width: 320px; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,0.14); margin-top: 34px; padding-top: 18px; font-size: 12.5px; color: rgba(255,255,255,0.55); display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px; }

.back-top { position: fixed; right: 22px; bottom: 22px; width: 44px; height: 44px; border-radius: 50%; background: var(--ink); color: #fff; border: none; cursor: pointer; display: none; align-items: center; justify-content: center; box-shadow: var(--shadow-md); z-index: 90; }
.back-top.show { display: flex; }

/* page accent variants */
.page-kitchen .eyebrow, .page-kitchen .cyan-accent { color: var(--orange-deep); background: rgba(217,139,70,0.1); }
.page-wellness .eyebrow { color: var(--green-deep); background: rgba(95,157,116,0.1); }
.page-robot .eyebrow { color: var(--mist-deep); background: rgba(63,91,120,0.1); }

/* ---------------- Responsive ---------------- */
@media (max-width: 1024px) {
  .hero .container { grid-template-columns: 1fr; }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 768px) {
  .main-nav { position: fixed; top: 72px; left: 0; right: 0; bottom: 0; background: var(--bg);
    flex-direction: column; align-items: stretch; padding: 16px; gap: 6px; overflow-y: auto;
    transform: translateX(100%); transition: transform 0.25s ease; }
  .main-nav.open { transform: translateX(0); }
  .main-nav a { padding: 13px 16px; font-size: 16px; }
  .nav-toggle { display: flex; }
  .hero h1 { font-size: 28px; }
  .section { padding: 44px 0; }
  .grid-3, .grid-4, .grid-2 { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .app-mock { grid-template-columns: repeat(2, 1fr); }
  .diagram-row { grid-template-columns: 1fr; }
}
@media (max-width: 430px) {
  .container { padding: 0 16px; }
  .article { padding: 26px 18px; }
  .page-hero h1 { font-size: 26px; }
  .footer-grid { grid-template-columns: 1fr; }
}