/* ============================================================
   源流智能 · 游戏视频核心利益识别引擎
   Light Theme · 白底
   ============================================================ */

:root {
  --bg: #ffffff;
  --bg-2: #f8fafc;
  --bg-3: #f1f5f9;
  --line: rgba(15, 23, 42, 0.08);
  --line-2: rgba(15, 23, 42, 0.14);
  --text: #0f172a;
  --text-mute: #475569;
  --text-dim: #94a3b8;

  --primary: #0d9488;        /* deep teal */
  --primary-2: #0891b2;      /* deep cyan */
  --accent: #7c3aed;         /* deep purple */
  --accent-2: #db2777;       /* deep pink */
  --warn: #d97706;
  --bad: #dc2626;
  --good: #16a34a;

  --grad-cool: linear-gradient(135deg, #0d9488 0%, #0891b2 50%, #7c3aed 100%);
  --grad-warm: linear-gradient(135deg, #db2777 0%, #7c3aed 50%, #0d9488 100%);
  --grad-full: linear-gradient(135deg, #0891b2 0%, #7c3aed 50%, #db2777 100%);

  --shadow-1: 0 4px 16px rgba(15, 23, 42, 0.06);
  --shadow-2: 0 8px 32px rgba(15, 23, 42, 0.10);
  --shadow-glow: 0 12px 40px rgba(13, 148, 136, 0.18);

  --r-sm: 8px;
  --r-md: 14px;
  --r-lg: 22px;
  --r-xl: 32px;

  --max-w: 1200px;

  /* Brand gradient — shared by nav brand "智能" + section accent words */
  --brand-gradient: linear-gradient(90deg, #3b82f6 0%, #8b5cf6 50%, #c026d3 100%);
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
  font-feature-settings: 'cv11', 'ss01';
}

a { color: inherit; text-decoration: none; }
img, video { max-width: 100%; display: block; }
button { font-family: inherit; cursor: pointer; border: 0; background: none; color: inherit; }

.container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
}

/* ========== shared section head ========== */
.section-head {
  text-align: center;
  margin-bottom: 64px;
}
.section-head .num {
  display: inline-block;
  font-family: 'JetBrains Mono', monospace;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.2em;
  color: var(--primary);
  text-transform: uppercase;
  padding: 6px 14px;
  border: 1px solid rgba(13, 148, 136, 0.3);
  border-radius: 100px;
  background: rgba(13, 148, 136, 0.06);
  margin-bottom: 20px;
}
.section-head h2 {
  font-size: clamp(28px, 4.2vw, 48px);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
  color: var(--text);
}
.section-head p {
  color: var(--text-mute);
  font-size: 16px;
  max-width: 720px;
  margin: 0 auto;
}

/* ========== NAV ========== */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  padding: 14px 0;
  background: rgba(255, 255, 255, 0.75);
  backdrop-filter: saturate(160%) blur(14px);
  -webkit-backdrop-filter: saturate(160%) blur(14px);
  border-bottom: 1px solid var(--line);
  transition: padding 0.2s ease, background 0.2s ease, box-shadow 0.2s;
}
.nav.is-scrolled {
  padding: 8px 0;
  background: rgba(255, 255, 255, 0.95);
  box-shadow: var(--shadow-1);
}
.nav-inner {
  display: flex;
  align-items: center;
  gap: 32px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  font-size: 17px;
  letter-spacing: -0.01em;
  flex-shrink: 0;
  color: var(--text);
}
.brand-mark { height: 32px; display: inline-flex; align-items: center; }
.brand-mark img { height: 32px; width: auto; max-width: 200px; display: block; object-fit: contain; }
.brand-mark.sm { height: 22px; }
.brand-mark.sm img { height: 22px; }
.brand-name em {
  font-style: normal;
  background: var(--brand-gradient);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  font-weight: 900;
}
.nav-links {
  display: flex;
  gap: 28px;
  flex: 1;
  justify-content: center;
}
.nav-links a {
  font-size: 14px;
  color: var(--text-mute);
  font-weight: 500;
  transition: color 0.2s;
}
.nav-links a:hover { color: var(--text); }
.nav-cta {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 9px 18px;
  background: var(--text);
  color: var(--bg) !important;
  font-weight: 700;
  font-size: 14px;
  border-radius: 100px;
  transition: transform 0.2s, box-shadow 0.2s;
}
.nav-cta:hover { transform: translateY(-1px); box-shadow: 0 8px 20px rgba(15, 23, 42, 0.18); }
.nav-cta svg { width: 14px; height: 14px; }
.nav-burger { display: none; }

/* ========== HERO ========== */
.hero {
  position: relative;
  padding: 160px 0 80px;
  overflow: hidden;
  isolation: isolate;
  background:
    radial-gradient(ellipse 80% 50% at 50% 0%, rgba(13, 148, 136, 0.10), transparent 60%),
    radial-gradient(ellipse 60% 50% at 90% 30%, rgba(124, 58, 237, 0.10), transparent 60%),
    radial-gradient(ellipse 50% 40% at 10% 60%, rgba(8, 145, 178, 0.08), transparent 60%),
    var(--bg);
}
.hero-bg {
  position: absolute;
  inset: 0;
  z-index: -1;
  background-image:
    linear-gradient(rgba(15, 23, 42, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(15, 23, 42, 0.035) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(ellipse 70% 50% at 50% 30%, black 30%, transparent 80%);
  -webkit-mask-image: radial-gradient(ellipse 70% 50% at 50% 30%, black 30%, transparent 80%);
}
.hero-glow {
  position: absolute;
  width: 480px; height: 480px;
  border-radius: 50%;
  filter: blur(120px);
  z-index: -1;
  opacity: 0.4;
  animation: float 14s ease-in-out infinite;
}
.hero-glow-1 { background: #5eead4; top: 10%; left: -120px; }
.hero-glow-2 { background: #c4b5fd; top: 30%; right: -120px; animation-delay: -5s; }
.hero-glow-3 { background: #fbcfe8; bottom: 5%; left: 30%; animation-delay: -9s; opacity: 0.3; }
@keyframes float {
  0%, 100% { transform: translate(0, 0) scale(1); }
  50% { transform: translate(40px, -30px) scale(1.1); }
}
.hero-inner { text-align: center; position: relative; }
.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 16px;
  border: 1px solid var(--line-2);
  background: rgba(255, 255, 255, 0.6);
  border-radius: 100px;
  font-size: 13px;
  color: var(--text-mute);
  margin-bottom: 28px;
  box-shadow: var(--shadow-1);
}
.hero-eyebrow .dot {
  width: 6px; height: 6px;
  background: var(--primary);
  border-radius: 50%;
  box-shadow: 0 0 8px var(--primary);
  animation: pulse 2s ease-in-out infinite;
}
@keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.5; } }
.hero-title {
  font-size: clamp(38px, 6.4vw, 76px);
  font-weight: 800;
  line-height: 1.05;
  letter-spacing: -0.035em;
  margin-bottom: 24px;
  color: var(--text);
}
.grad-text {
  background: var(--grad-warm);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.accent-text {
  background: var(--brand-gradient);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  font-weight: 900;
  padding: 0 2px;
}
.grad-text-strong {
  background: var(--grad-full);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.hero-sub {
  font-size: clamp(15px, 1.4vw, 18px);
  color: var(--text-mute);
  max-width: 680px;
  margin: 0 auto 36px;
  line-height: 1.7;
}
.hero-cta {
  display: flex;
  gap: 14px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 72px;
}
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 26px;
  font-size: 15px;
  font-weight: 700;
  border-radius: 100px;
  transition: transform 0.2s, box-shadow 0.2s, background 0.2s, border-color 0.2s;
  cursor: pointer;
  white-space: nowrap;
}
.btn svg { width: 16px; height: 16px; }
.btn-primary {
  background: var(--text);
  color: var(--bg);
  box-shadow: 0 8px 24px rgba(15, 23, 42, 0.18);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 12px 32px rgba(15, 23, 42, 0.28); }
.btn-ghost {
  background: var(--bg);
  border: 1px solid var(--line-2);
  color: var(--text);
  box-shadow: var(--shadow-1);
}
.btn-ghost:hover {
  background: var(--bg-2);
  border-color: var(--primary);
  color: var(--primary);
  transform: translateY(-2px);
}
.btn-block { width: 100%; justify-content: center; padding: 16px 26px; }

.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  max-width: 880px;
  margin: 0 auto 64px;
  padding: 32px;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--r-xl);
  box-shadow: var(--shadow-1);
}
.stat { text-align: center; }
.stat-num {
  font-size: clamp(28px, 3.2vw, 44px);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.1;
  background: var(--grad-full);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  margin-bottom: 8px;
}
.stat-num small {
  font-size: 0.5em;
  font-weight: 700;
  -webkit-text-fill-color: var(--text);
  color: var(--text);
  margin-left: 2px;
}
.stat-label {
  font-size: 13px;
  color: var(--text-mute);
  line-height: 1.5;
}

.hero-marquee {
  margin: 0 -24px;
  padding: 16px 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  overflow: hidden;
  background: var(--bg-2);
  mask-image: linear-gradient(to right, transparent, black 8%, black 92%, transparent);
  -webkit-mask-image: linear-gradient(to right, transparent, black 8%, black 92%, transparent);
}
.marquee-track {
  display: inline-flex;
  gap: 32px;
  font-size: 13px;
  color: var(--text-mute);
  white-space: nowrap;
  animation: marquee 50s linear infinite;
  font-weight: 500;
}
.marquee-track span:nth-child(2n) { color: var(--text-dim); }
@keyframes marquee { from { transform: translateX(0); } to { transform: translateX(-50%); } }

/* ========== PAIN ========== */
.pain {
  padding: 120px 0;
  background: var(--bg-2);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.pain-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.pain-card {
  padding: 36px 32px;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  transition: transform 0.3s, border-color 0.3s, box-shadow 0.3s;
}
.pain-card:hover {
  transform: translateY(-4px);
  border-color: rgba(13, 148, 136, 0.3);
  box-shadow: var(--shadow-glow);
}
.pain-icon {
  margin-bottom: 18px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 56px; height: 56px;
  border-radius: 14px;
  background: rgba(220, 38, 38, 0.1);
  color: var(--bad);
}
.pain-icon svg { width: 30px; height: 30px; }
.pain-card:nth-child(2) .pain-icon { background: rgba(217, 119, 6, 0.1); color: var(--warn); }
.pain-card:nth-child(3) .pain-icon { background: rgba(124, 58, 237, 0.1); color: var(--accent); }
.pain-card h3 {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 12px;
  letter-spacing: -0.01em;
  color: var(--text);
}
.pain-card p {
  color: var(--text-mute);
  font-size: 14.5px;
  line-height: 1.7;
}

/* ========== CAPABILITIES (11 类) ========== */
.caps {
  padding: 120px 0;
  background: var(--bg);
}
.caps-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}
.cap {
  position: relative;
  padding: 24px 20px 20px;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  overflow: hidden;
  transition: transform 0.25s, border-color 0.25s, box-shadow 0.25s;
}
.cap:hover { transform: translateY(-3px); border-color: var(--line-2); box-shadow: var(--shadow-2); }
.cap-stripe {
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 4px;
}
.cap[data-tone="0"] .cap-stripe { background: linear-gradient(90deg, #94a3b8, #cbd5e1); }
.cap[data-tone="1"] .cap-stripe { background: linear-gradient(90deg, #67e8f9, #0891b2); }
.cap[data-tone="2"] .cap-stripe { background: linear-gradient(90deg, #5eead4, #0d9488); }
.cap[data-tone="3"] .cap-stripe { background: linear-gradient(90deg, #6ee7b7, #059669); }
.cap[data-tone="4"] .cap-stripe { background: linear-gradient(90deg, #fde68a, #d97706); }
.cap[data-tone="5"] .cap-stripe { background: linear-gradient(90deg, #fdba74, #ea580c); }
.cap[data-tone="6"] .cap-stripe { background: linear-gradient(90deg, #fca5a5, #dc2626); }
.cap[data-tone="7"] .cap-stripe { background: linear-gradient(90deg, #f9a8d4, #db2777); }
.cap[data-tone="8"] .cap-stripe { background: linear-gradient(90deg, #d8b4fe, #7c3aed); }
.cap[data-tone="9"] .cap-stripe { background: linear-gradient(90deg, #c4b5fd, #6d28d9); }
.cap[data-tone="10"] .cap-stripe { background: linear-gradient(90deg, #93c5fd, #2563eb); }
.cap-code {
  font-family: 'JetBrains Mono', monospace;
  font-size: 13px;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--text-dim);
}
.cap-title {
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 8px;
  letter-spacing: -0.005em;
  color: var(--text);
}
.cap p {
  font-size: 13px;
  color: var(--text-mute);
  line-height: 1.6;
}

/* ========== CASES (视频实例) ========== */
.cases {
  padding: 120px 0;
  background: var(--bg-2);
  border-top: 1px solid var(--line);
}
.case-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}
.case-card {
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  overflow: hidden;
  cursor: pointer;
  transition: transform 0.3s, border-color 0.3s, box-shadow 0.3s;
  position: relative;
}
.case-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-2);
}
.case-media {
  position: relative;
  aspect-ratio: 16 / 9;
  background: #000;
  overflow: hidden;
}
.case-media video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s, filter 0.3s;
}
.case-card:hover .case-media video { transform: scale(1.04); filter: brightness(1.05); }
.case-overlay {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(180deg, transparent 30%, rgba(0, 0, 0, 0.5));
  pointer-events: none;
  transition: opacity 0.3s;
}
.case-overlay svg {
  width: 56px; height: 56px;
  color: rgba(255, 255, 255, 0.9);
  filter: drop-shadow(0 4px 12px rgba(0, 0, 0, 0.4));
  transition: transform 0.3s, color 0.3s;
}
.case-card:hover .case-overlay svg { transform: scale(1.15); color: #fff; }
.case-card:hover .case-overlay { opacity: 0.4; }
.case-tag {
  position: absolute;
  top: 14px; left: 14px;
  padding: 6px 12px;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(8px);
  border: 1px solid rgba(255, 255, 255, 0.4);
  border-radius: 100px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px;
  font-weight: 700;
  color: var(--text);
  letter-spacing: 0.02em;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
}
.case-body { padding: 22px 24px 24px; }
.case-body h3 {
  font-size: 17px;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin-bottom: 10px;
  line-height: 1.4;
  color: var(--text);
}
.case-body p {
  font-size: 14px;
  color: var(--text-mute);
  line-height: 1.65;
  margin-bottom: 14px;
}
.case-body p strong { color: var(--text); font-weight: 600; }
.case-meta {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 12.5px;
  color: var(--text-dim);
  flex-wrap: wrap;
}
.case-meta .game { color: var(--primary); font-weight: 600; }
.case-meta .dot-sep { color: var(--text-dim); }
.case-meta .verdict b {
  color: var(--good);
  font-family: 'JetBrains Mono', monospace;
  font-weight: 700;
}

/* 类别色调装饰（左侧色条） */
.case-card[data-tone="1"] { box-shadow: -3px 0 0 #16a34a, 0 0 0 transparent; border-color: rgba(22, 163, 74, 0.2); }
.case-card[data-tone="2"] { box-shadow: -3px 0 0 #16a34a, 0 0 0 transparent; border-color: rgba(22, 163, 74, 0.2); }
.case-card[data-tone="3"] { box-shadow: -3px 0 0 #059669, 0 0 0 transparent; border-color: rgba(5, 150, 105, 0.2); }
.case-card[data-tone="4"] { box-shadow: -3px 0 0 #d97706, 0 0 0 transparent; border-color: rgba(217, 119, 6, 0.2); }
.case-card[data-tone="5"] { box-shadow: -3px 0 0 #ea580c, 0 0 0 transparent; border-color: rgba(234, 88, 12, 0.2); }
.case-card[data-tone="6"] { box-shadow: -3px 0 0 #dc2626, 0 0 0 transparent; border-color: rgba(220, 38, 38, 0.2); }
.case-card[data-tone="7"] { box-shadow: -3px 0 0 #db2777, 0 0 0 transparent; border-color: rgba(219, 39, 119, 0.2); }
.case-card[data-tone="8"] { box-shadow: -3px 0 0 #7c3aed, 0 0 0 transparent; border-color: rgba(124, 58, 237, 0.2); }
.case-card[data-tone="9"] { box-shadow: -3px 0 0 #dc2626, 0 0 0 transparent; border-color: rgba(220, 38, 38, 0.2); }
.case-card[data-tone="10"] { box-shadow: -3px 0 0 #dc2626, 0 0 0 transparent; border-color: rgba(220, 38, 38, 0.2); }
.case-card:hover[data-tone] { box-shadow: -3px 0 0 currentColor, 0 12px 32px rgba(15, 23, 42, 0.12); }

/* ========== CAPABILITY (模型能力) ========== */
.capability {
  padding: 120px 0;
  background: var(--bg);
}
.capability h2 em {
  font-style: normal;
  background: var(--grad-cool);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  font-weight: 800;
}
.cap-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-bottom: 32px;
}
.cap-card {
  position: relative;
  padding: 28px 28px 56px;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  box-shadow: var(--shadow-1);
  transition: transform 0.3s, box-shadow 0.3s, border-color 0.3s;
}
.cap-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-2);
  border-color: rgba(13, 148, 136, 0.25);
}
.cap-card-head { margin-bottom: 20px; }
.cap-card-name {
  font-family: 'JetBrains Mono', monospace;
  font-size: 18px;
  font-weight: 800;
  letter-spacing: 0.04em;
  color: var(--text);
}
.cap-card-body { display: flex; flex-direction: column; gap: 8px; }
.cap-row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
}
.cap-row-label {
  font-size: 13.5px;
  font-weight: 600;
  color: var(--text);
  display: inline-flex;
  align-items: center;
  gap: 8px;
}
.cap-row-label.is-tag {
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--primary);
  text-transform: uppercase;
}
.cap-row-ours-tag {
  font-family: 'JetBrains Mono', monospace;
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.08em;
  padding: 2px 7px;
  background: var(--primary);
  color: #fff;
  border-radius: 4px;
  text-transform: none;
}
.cap-row-num {
  font-size: 28px;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--text);
  line-height: 1;
  display: inline-flex;
  align-items: baseline;
  gap: 2px;
}
.cap-row-num-ours {
  background: var(--grad-cool);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.cap-row-den {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-dim);
  -webkit-text-fill-color: var(--text-dim);
  margin-left: 6px;
}
.cap-track {
  height: 8px;
  background: var(--bg-3);
  border-radius: 4px;
  overflow: hidden;
  margin-bottom: 10px;
}
.cap-fill {
  height: 100%;
  border-radius: 4px;
  transform-origin: left;
  transition: width 1.2s cubic-bezier(0.16, 1, 0.3, 1);
}
.cap-fill-base { background: #94a3b8; }
.cap-fill-ours {
  background: var(--grad-cool);
  box-shadow: 0 0 12px rgba(8, 145, 178, 0.3);
}
.cap-delta {
  position: absolute;
  left: 50%;
  bottom: 20px;
  transform: translateX(-50%);
  padding: 6px 16px;
  background: #f59e0b;
  color: #fff;
  font-family: 'JetBrains Mono', monospace;
  font-size: 13px;
  font-weight: 700;
  border-radius: 100px;
  box-shadow: 0 4px 12px rgba(245, 158, 11, 0.35);
  white-space: nowrap;
}

/* TTFT callout bar */
.ttft-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 24px 32px;
  padding: 24px 32px;
  background: var(--bg);
  border: 1px solid var(--line);
  border-left: 4px solid var(--primary);
  border-radius: var(--r-md);
  box-shadow: var(--shadow-1);
}
.ttft-tags {
  margin-left: auto;
}
.ttft-main { display: flex; flex-direction: column; gap: 4px; }
.ttft-label {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-mute);
  font-family: 'JetBrains Mono', monospace;
}
.ttft-sublabel {
  font-size: 12px;
  font-weight: 500;
  color: var(--text-dim);
  margin-top: -2px;
}
.ttft-num {
  font-size: 36px;
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1;
  background: var(--grad-cool);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.ttft-unit {
  font-size: 0.5em;
  font-weight: 700;
  -webkit-text-fill-color: var(--text);
  color: var(--text);
  margin-left: 4px;
}
.ttft-divider { width: 1px; height: 48px; background: var(--line); }
.ttft-tags { display: flex; flex-direction: column; gap: 8px; }
.ttft-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  font-weight: 600;
  color: var(--text);
  font-family: 'JetBrains Mono', monospace;
  white-space: nowrap;
  flex-shrink: 0;
}
.ttft-tag-break {
  flex-basis: 100%;
}
.ttft-dot {
  width: 8px; height: 8px;
  background: var(--primary);
  border-radius: 50%;
  box-shadow: 0 0 6px var(--primary);
  flex-shrink: 0;
}
.ttft-foot {
  font-size: 12.5px;
  color: var(--text-mute);
  text-align: right;
  font-style: italic;
}

/* other-input: shown when "其他" chip is checked */
.other-input {
  display: none;
  margin-top: 10px;
  font-family: inherit;
  font-size: 14px;
  padding: 12px 14px;
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: var(--r-sm);
  color: var(--text);
  transition: border-color 0.2s, background 0.2s, box-shadow 0.2s;
  width: 100%;
}
.other-input.is-visible { display: block; }
.other-input::placeholder { color: var(--text-dim); }
.other-input:focus {
  outline: none;
  border-color: var(--primary);
  background: var(--bg);
  box-shadow: 0 0 0 3px rgba(13, 148, 136, 0.12);
}

/* ========== AI CASES PLACEHOLDERS ========== */
.case-card-placeholder {
  cursor: default;
}
.case-card-placeholder:hover { transform: none; box-shadow: var(--shadow-1); }
.case-card-placeholder .case-overlay { display: none; }
.case-media-placeholder {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 14px;
  color: rgba(255, 255, 255, 0.95);
  text-align: center;
  padding: 24px;
}
.case-media-placeholder svg {
  width: 64px; height: 64px;
  opacity: 0.85;
  filter: drop-shadow(0 4px 12px rgba(0, 0, 0, 0.2));
}
.placeholder-label {
  font-family: 'JetBrains Mono', monospace;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.05em;
  padding: 6px 14px;
  background: rgba(255, 255, 255, 0.18);
  border: 1px solid rgba(255, 255, 255, 0.3);
  border-radius: 100px;
  backdrop-filter: blur(6px);
}
.tone-real-1 { background: linear-gradient(135deg, #0c4a6e 0%, #0e7490 50%, #0891b2 100%); }
.tone-real-2 { background: linear-gradient(135deg, #1e3a8a 0%, #1d4ed8 50%, #3b82f6 100%); }
.tone-ai-1   { background: linear-gradient(135deg, #6b21a8 0%, #a21caf 50%, #db2777 100%); }
.tone-ai-2   { background: linear-gradient(135deg, #831843 0%, #be185d 50%, #f472b6 100%); }

/* AI 占位卡左侧色条用色 */
.case-card-placeholder[data-tone="1"]  { box-shadow: -3px 0 0 #0891b2, 0 0 0 transparent; border-color: rgba(8, 145, 178, 0.2); }
.case-card-placeholder[data-tone="2"]  { box-shadow: -3px 0 0 #3b82f6, 0 0 0 transparent; border-color: rgba(59, 130, 246, 0.2); }
.case-card-placeholder[data-tone="9"]  { box-shadow: -3px 0 0 #a21caf, 0 0 0 transparent; border-color: rgba(162, 28, 175, 0.2); }
.case-card-placeholder[data-tone="10"] { box-shadow: -3px 0 0 #f472b6, 0 0 0 transparent; border-color: rgba(244, 114, 182, 0.2); }

/* ========== EXTEND (能力延伸) ========== */
.extend {
  padding: 120px 0;
  background: var(--bg-2);
  border-top: 1px solid var(--line);
}
.extend-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-bottom: 40px;
}
.extend-card {
  padding: 32px 26px 26px;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  transition: transform 0.3s, border-color 0.3s, box-shadow 0.3s;
  position: relative;
  overflow: hidden;
}
.extend-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: var(--grad-cool);
  opacity: 0;
  transition: opacity 0.3s;
}
.extend-card:hover {
  transform: translateY(-4px);
  border-color: rgba(13, 148, 136, 0.3);
  box-shadow: var(--shadow-2);
}
.extend-card:hover::before { opacity: 1; }
.extend-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 52px; height: 52px;
  background: linear-gradient(135deg, rgba(13, 148, 136, 0.1), rgba(124, 58, 237, 0.1));
  border-radius: 14px;
  color: var(--primary);
  margin-bottom: 18px;
  transition: transform 0.3s;
}
.extend-card:hover .extend-icon { transform: scale(1.08) rotate(-4deg); }
.extend-icon svg { width: 26px; height: 26px; }
.extend-card h3 {
  font-size: 17px;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin-bottom: 10px;
  color: var(--text);
}
.extend-card p {
  font-size: 13.5px;
  color: var(--text-mute);
  line-height: 1.7;
  margin-bottom: 16px;
}
.extend-tag {
  display: inline-block;
  font-family: 'JetBrains Mono', monospace;
  font-size: 11px;
  font-weight: 600;
  padding: 4px 10px;
  background: var(--bg-3);
  color: var(--text-mute);
  border-radius: 100px;
  letter-spacing: 0.02em;
}
/* ========== SCENARIOS ========== */
.scenes {
  padding: 120px 0;
  background: var(--bg);
}
.scene-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.scene {
  padding: 32px 28px;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  position: relative;
  transition: transform 0.3s, border-color 0.3s, box-shadow 0.3s;
}
.scene:hover { transform: translateY(-3px); border-color: rgba(13, 148, 136, 0.3); box-shadow: var(--shadow-1); }
.scene-num {
  position: absolute;
  top: 24px; right: 24px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 12px;
  font-weight: 700;
  color: var(--text-dim);
  letter-spacing: 0.05em;
}
.scene h3 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 10px;
  letter-spacing: -0.01em;
  padding-right: 40px;
  color: var(--text);
}
.scene p {
  font-size: 14px;
  color: var(--text-mute);
  line-height: 1.7;
}

/* ========== CTA ========== */
.cta {
  padding: 120px 0;
  background: var(--bg-2);
  border-top: 1px solid var(--line);
  position: relative;
  overflow: hidden;
}
.cta::before {
  content: '';
  position: absolute;
  width: 600px; height: 600px;
  background: radial-gradient(circle, rgba(13, 148, 136, 0.10), transparent 60%);
  filter: blur(80px);
  top: -100px; right: -100px;
  z-index: 0;
  pointer-events: none;
}
.cta-inner {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 64px;
  align-items: center;
  position: relative;
}
.cta-glow { display: none; }
.cta-text { position: relative; }
.cta-text h2 {
  font-size: clamp(38px, 4.8vw, 52px);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.025em;
  margin-bottom: 20px;
  color: var(--text);
}
.cta-text p { color: var(--text-mute); font-size: 16px; line-height: 1.7; }

.cta-form {
  position: relative;
  padding: 32px;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  display: flex;
  flex-direction: column;
  gap: 16px;
  box-shadow: var(--shadow-2);
}
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.cta-form label { display: flex; flex-direction: column; gap: 6px; }
.cta-form label > span {
  font-size: 12.5px;
  font-weight: 600;
  color: var(--text-mute);
  letter-spacing: 0.02em;
}
.form-field { display: flex; flex-direction: column; gap: 6px; }
.field-label {
  font-size: 12.5px;
  font-weight: 600;
  color: var(--text-mute);
  letter-spacing: 0.02em;
}
.cta-form input, .cta-form textarea {
  font-family: inherit;
  font-size: 14px;
  padding: 12px 14px;
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: var(--r-sm);
  color: var(--text);
  resize: vertical;
  transition: border-color 0.2s, background 0.2s, box-shadow 0.2s;
}
.cta-form input::placeholder, .cta-form textarea::placeholder {
  color: var(--text-dim);
}
.cta-form input:focus, .cta-form textarea:focus {
  outline: none;
  border-color: var(--primary);
  background: var(--bg);
  box-shadow: 0 0 0 3px rgba(13, 148, 136, 0.12);
}
.chips { display: flex; flex-wrap: wrap; gap: 8px; }
.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 12px;
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: 100px;
  font-size: 12.5px;
  font-weight: 500;
  color: var(--text-mute);
  cursor: pointer;
  user-select: none;
  transition: all 0.2s;
}
.chip:hover { border-color: var(--primary); color: var(--primary); }
.chip input { display: none; }
.chip:has(input:checked) {
  background: rgba(13, 148, 136, 0.1);
  border-color: var(--primary);
  color: var(--primary);
}
.form-ok {
  color: var(--good);
  font-size: 14px;
  font-weight: 600;
  text-align: center;
  padding: 12px;
  background: rgba(22, 163, 74, 0.08);
  border-radius: var(--r-sm);
}
.form-ok.is-error {
  color: #dc2626;
  background: rgba(220, 38, 38, 0.08);
}
.consent {
  flex-direction: row !important;
  align-items: flex-start;
  gap: 9px !important;
  cursor: pointer;
}
.consent input {
  width: 16px;
  height: 16px;
  margin-top: 1px;
  padding: 0;
  flex: 0 0 auto;
  accent-color: var(--primary);
}
.consent > span { line-height: 1.5; }
.form-trap {
  position: absolute !important;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
}
.cta-form button:disabled { opacity: 0.65; cursor: wait; }
.form-foot {
  text-align: center;
  font-size: 12.5px;
  color: var(--text-dim);
  margin-top: 4px;
}
.form-foot a { color: var(--primary); font-weight: 500; }
.form-foot a:hover { text-decoration: underline; }

/* ========== FOOTER ========== */
.foot {
  padding: 32px 0;
  background: var(--bg);
  border-top: 1px solid var(--line);
}
.foot-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 13px;
  color: var(--text-dim);
}
.foot-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
  color: var(--text-mute);
}
.foot-meta {
  font-family: 'JetBrains Mono', monospace;
  font-size: 12px;
}

/* ========== MODAL ========== */
.modal {
  position: fixed;
  inset: 0;
  z-index: 200;
  background: rgba(15, 23, 42, 0.75);
  backdrop-filter: blur(8px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 40px 24px;
  animation: fadeIn 0.2s;
}
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
.modal[hidden] { display: none; }
.modal-close {
  position: absolute;
  top: 24px; right: 24px;
  width: 44px; height: 44px;
  background: var(--bg);
  border: 1px solid var(--line-2);
  border-radius: 50%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  transition: background 0.2s, transform 0.2s;
  z-index: 10;
  color: var(--text);
  box-shadow: var(--shadow-1);
}
.modal-close:hover { background: var(--bg-2); transform: rotate(90deg); }
.modal-close svg { width: 20px; height: 20px; }
.modal-inner {
  display: grid;
  grid-template-columns: 1.6fr 1fr;
  gap: 32px;
  max-width: 1280px;
  width: 100%;
  max-height: calc(100vh - 80px);
}
.modal-video {
  background: #000;
  border-radius: var(--r-lg);
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 24px 60px rgba(15, 23, 42, 0.3);
}
.modal-video video { width: 100%; max-height: calc(100vh - 80px); }
.modal-info {
  padding: 24px 8px;
  overflow-y: auto;
  color: var(--text);
}
.modal-tag {
  display: inline-block;
  padding: 6px 14px;
  background: rgba(13, 148, 136, 0.1);
  border: 1px solid rgba(13, 148, 136, 0.3);
  border-radius: 100px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 12px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 16px;
  letter-spacing: 0.02em;
}
.modal-info h3 {
  font-size: 24px;
  font-weight: 800;
  letter-spacing: -0.02em;
  margin-bottom: 12px;
  line-height: 1.3;
  color: var(--text);
}
.modal-info p {
  font-size: 15px;
  color: var(--text-mute);
  line-height: 1.75;
}
.modal-info p strong { color: var(--text); font-weight: 600; }

/* ========== RESPONSIVE ========== */
@media (max-width: 1024px) {
  .caps-grid { grid-template-columns: repeat(3, 1fr); }
  .case-grid { grid-template-columns: 1fr; }
  .extend-grid { grid-template-columns: repeat(2, 1fr); }
  .cta-inner { grid-template-columns: 1fr; gap: 40px; }
  .modal-inner { grid-template-columns: 1fr; max-height: 90vh; overflow-y: auto; }
  .modal-video video { max-height: 50vh; }
}
@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav-cta { display: none; }
  .nav-burger {
    display: flex;
    flex-direction: column;
    gap: 4px;
    width: 36px; height: 36px;
    align-items: center;
    justify-content: center;
    margin-left: auto;
  }
  .nav-burger span {
    width: 20px; height: 2px;
    background: var(--text);
    border-radius: 2px;
  }
  .hero { padding: 120px 0 60px; }
  .hero-stats { grid-template-columns: repeat(2, 1fr); padding: 20px; gap: 12px; }
  .pain, .caps, .cases, .capability, .extend, .scenes, .cta { padding: 72px 0; }
  .pain-grid, .rule-grid, .scene-grid { grid-template-columns: 1fr; }
  .caps-grid { grid-template-columns: repeat(2, 1fr); }
  .extend-grid { grid-template-columns: 1fr; }
  .cap-grid { grid-template-columns: 1fr; }
  .ttft-bar {
    grid-template-columns: 1fr;
    gap: 16px;
    padding: 20px;
  }
  .ttft-divider { display: none; }
  .ttft-foot { text-align: left; }
  .ar-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .section-head { margin-bottom: 40px; }
  .container { padding: 0 20px; }
}
@media (max-width: 480px) {
  .caps-grid { grid-template-columns: 1fr; }
}

/* ========== SPACING + GROUP HEAD (in 03 merged section) ========== */
.caps-grid {
  margin-bottom: 140px;
}
.case-group-head {
  text-align: center;
  margin-top: 0;
  margin-bottom: 80px;
  padding-top: 48px;
  border-top: 1px solid var(--line);
}
.case-group-head h3 {
  font-size: clamp(28px, 4.2vw, 48px);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.15;
  color: var(--text);
}