:root {
  --bg-primary: #FFFFFF;
  --bg-secondary: #F4F5F7;
  --bg-tertiary: #E8EBED;
  --bg-dark: #191F28;
  --bg-card: #FFFFFF;
  --text-primary: #191F28;
  --text-secondary: #4E5968;
  --text-tertiary: #8B95A1;
  --text-inverse: #FFFFFF;
  --blue: #3182F6;
  --blue-light: #EBF3FF;
  --green: #03B26C;
  --green-light: #E8F7F0;
  --red: #F04452;
  --red-light: #FFEFF0;
  --purple: #8B5CF6;
  --purple-light: #F0EBFF;
  --openai: #10A37F;
  --openai-light: #E6F7F2;
  --gemini: #4285F4;
  --gemini-light: #EBF3FF;
  --claude: #D97757;
  --claude-light: #FDF0EB;
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.08);
  --shadow-lg: 0 8px 32px rgba(0,0,0,0.10);
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 20px;
  --radius-2xl: 24px;
  --radius-full: 9999px;
  --transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

*, *::before, *::after { margin:0; padding:0; box-sizing:border-box; }
html { scroll-behavior:smooth; -webkit-font-smoothing:antialiased; }
body { font-family:var(--font); background:var(--bg-secondary); color:var(--text-primary); line-height:1.6; overflow-x:hidden; }
::-webkit-scrollbar { width:6px; }
::-webkit-scrollbar-track { background:transparent; }
::-webkit-scrollbar-thumb { background:var(--bg-tertiary); border-radius:3px; }

/* ===== Nav ===== */
.nav { position:fixed; top:0; left:0; right:0; z-index:100; background:rgba(255,255,255,0.85); backdrop-filter:blur(20px) saturate(180%); -webkit-backdrop-filter:blur(20px) saturate(180%); border-bottom:1px solid rgba(0,0,0,0.06); }
.nav-inner { max-width:1200px; margin:0 auto; padding:0 24px; height:64px; display:flex; align-items:center; justify-content:space-between; }
.nav-logo { display:flex; align-items:center; gap:10px; font-weight:800; font-size:18px; color:var(--text-primary); text-decoration:none; letter-spacing:-0.3px; }
.nav-logo-icon { width:32px; height:32px; background:var(--blue); border-radius:var(--radius-sm); display:flex; align-items:center; justify-content:center; color:white; font-size:16px; }
.nav-links { display:flex; gap:2px; list-style:none; }
.nav-link { padding:8px 14px; border-radius:var(--radius-full); font-size:13px; font-weight:500; color:var(--text-secondary); cursor:pointer; transition:var(--transition); text-decoration:none; white-space:nowrap; }
.nav-link:hover { background:var(--bg-secondary); color:var(--text-primary); }
.nav-link.active { background:var(--blue-light); color:var(--blue); font-weight:600; }
.nav-mobile-toggle { display:none; width:40px; height:40px; border:none; background:none; font-size:20px; cursor:pointer; color:var(--text-primary); border-radius:var(--radius-sm); align-items:center; justify-content:center; }

/* ===== Hero ===== */
.hero { padding:140px 24px 80px; text-align:center; background:linear-gradient(180deg, #FFFFFF 0%, #F4F5F7 100%); position:relative; overflow:hidden; }
.hero::before { content:''; position:absolute; top:-200px; left:50%; transform:translateX(-50%); width:800px; height:800px; background:radial-gradient(circle, rgba(49,130,246,0.06) 0%, transparent 70%); pointer-events:none; }
.hero-badge { display:inline-flex; align-items:center; gap:6px; padding:6px 14px; background:var(--blue-light); color:var(--blue); border-radius:var(--radius-full); font-size:13px; font-weight:600; margin-bottom:24px; }
.hero h1 { font-size:52px; font-weight:900; line-height:1.15; letter-spacing:-1.5px; margin-bottom:16px; max-width:700px; margin-left:auto; margin-right:auto; }
.hero h1 .gradient-text { background:linear-gradient(135deg, var(--blue) 0%, #8B5CF6 50%, var(--blue) 100%); background-size:200% auto; -webkit-background-clip:text; -webkit-text-fill-color:transparent; background-clip:text; animation:gradient-shift 3s ease infinite; }
@keyframes gradient-shift { 0%,100%{background-position:0% center} 50%{background-position:100% center} }
.hero-desc { font-size:18px; color:var(--text-secondary); max-width:620px; margin:0 auto 40px; line-height:1.7; }
.hero-stats { display:flex; justify-content:center; gap:48px; flex-wrap:wrap; }
.hero-stat { text-align:center; }
.hero-stat-value { font-size:36px; font-weight:800; color:var(--blue); letter-spacing:-1px; }
.hero-stat-label { font-size:13px; color:var(--text-tertiary); font-weight:500; margin-top:4px; }

/* ===== Container & Section ===== */
.container { max-width:1200px; margin:0 auto; padding:0 24px; }
.section { padding:80px 0; }
.section-header { text-align:center; margin-bottom:56px; }
.section-label { display:inline-flex; align-items:center; gap:6px; padding:5px 12px; background:var(--bg-tertiary); border-radius:var(--radius-full); font-size:12px; font-weight:600; color:var(--text-secondary); text-transform:uppercase; letter-spacing:0.5px; margin-bottom:16px; }
.section-title { font-size:36px; font-weight:800; letter-spacing:-0.8px; margin-bottom:12px; }
.section-desc { font-size:16px; color:var(--text-tertiary); max-width:520px; margin:0 auto; line-height:1.6; }

/* ===== Fundamental Cards ===== */
.fundamentals-grid { display:grid; grid-template-columns:repeat(3,1fr); gap:16px; }
.fundamental-card { background:var(--bg-card); border-radius:var(--radius-lg); padding:28px; cursor:pointer; transition:var(--transition); border:1px solid transparent; position:relative; overflow:hidden; }
.fundamental-card:hover { transform:translateY(-2px); box-shadow:var(--shadow-md); border-color:var(--blue); }
.fundamental-card-icon { font-size:32px; margin-bottom:16px; display:block; }
.fundamental-card h3 { font-size:17px; font-weight:700; letter-spacing:-0.3px; margin-bottom:4px; }
.fundamental-card .subtitle { font-size:12px; color:var(--text-tertiary); font-weight:500; margin-bottom:12px; }
.fundamental-card p { font-size:14px; color:var(--text-secondary); line-height:1.65; display:-webkit-box; -webkit-line-clamp:3; -webkit-box-orient:vertical; overflow:hidden; }
.fundamental-card .card-arrow { position:absolute; top:28px; right:28px; width:28px; height:28px; border-radius:var(--radius-full); background:var(--bg-secondary); display:flex; align-items:center; justify-content:center; font-size:12px; color:var(--text-tertiary); transition:var(--transition); }
.fundamental-card:hover .card-arrow { background:var(--blue); color:white; }

/* ===== Cost Compare ===== */
.cost-grid { display:grid; grid-template-columns:repeat(2,1fr); gap:16px; }
.cost-card { background:var(--bg-card); border-radius:var(--radius-lg); padding:28px; border:1px solid transparent; transition:var(--transition); }
.cost-card:hover { box-shadow:var(--shadow-sm); border-color:var(--blue); }
.cost-card-header { display:flex; align-items:center; gap:12px; margin-bottom:20px; }
.cost-card-icon { font-size:28px; }
.cost-card-name { font-size:16px; font-weight:700; letter-spacing:-0.3px; }
.cost-card-sub { font-size:12px; color:var(--text-tertiary); font-weight:500; line-height:1.4; margin-top:2px; }
.cost-card-versus { display:grid; grid-template-columns:1fr auto 1fr; gap:12px; align-items:center; margin-bottom:16px; }
.cost-vs-box { padding:14px; border-radius:var(--radius-md); text-align:center; }
.cost-vs-box.bulk { background:#EBF3FF; }
.cost-vs-box.many { background:#FFEFF0; }
.cost-vs-label { font-size:11px; font-weight:700; text-transform:uppercase; letter-spacing:0.5px; margin-bottom:6px; }
.cost-vs-box.bulk .cost-vs-label { color:var(--blue); }
.cost-vs-box.many .cost-vs-label { color:#F04452; }
.cost-vs-scenario { font-size:12px; color:var(--text-secondary); margin-bottom:6px; font-weight:500; }
.cost-vs-price { font-size:22px; font-weight:800; color:var(--text-primary); letter-spacing:-0.5px; }
.cost-vs-detail { font-size:11px; color:var(--text-tertiary); margin-top:4px; }
.cost-vs-divider { display:flex; align-items:center; justify-content:center; }
.cost-vs-badge { padding:4px 10px; border-radius:var(--radius-full); font-size:13px; font-weight:800; white-space:nowrap; }
.cost-card-verdict { padding:10px 14px; border-radius:var(--radius-sm); font-size:13px; font-weight:600; display:flex; align-items:center; gap:8px; margin-bottom:12px; }
.cost-card-tip { font-size:12px; color:var(--text-secondary); display:flex; align-items:flex-start; gap:6px; line-height:1.5; }
.cost-card-tip i { margin-top:2px; flex-shrink:0; }

.cost-summary { background:var(--bg-card); border-radius:var(--radius-lg); padding:32px; margin-top:24px; border:1px solid var(--bg-tertiary); }
.cost-summary-title { font-size:18px; font-weight:700; margin-bottom:16px; display:flex; align-items:center; gap:8px; }
.cost-summary-items { display:flex; flex-direction:column; gap:12px; }
.cost-summary-item { font-size:14px; color:var(--text-secondary); line-height:1.65; padding:12px 16px; background:var(--bg-secondary); border-radius:var(--radius-sm); }

/* ===== AI Service Cards ===== */
.ai-services-grid { display:grid; grid-template-columns:repeat(3,1fr); gap:20px; }
.ai-card { background:var(--bg-card); border-radius:var(--radius-xl); overflow:hidden; cursor:pointer; transition:var(--transition-slow); border:1.5px solid transparent; }
.ai-card:hover { transform:translateY(-4px); box-shadow:var(--shadow-lg); }
.ai-card[data-service="openai-gpt"]:hover { border-color:var(--openai); }
.ai-card[data-service="google-gemini"]:hover { border-color:var(--gemini); }
.ai-card[data-service="anthropic-claude"]:hover { border-color:var(--claude); }
.ai-card-header { padding:28px 24px 20px; position:relative; }
.ai-card-header::after { content:''; position:absolute; bottom:0; left:24px; right:24px; height:1px; background:var(--bg-secondary); }
.ai-card-logo { width:48px; height:48px; border-radius:var(--radius-md); display:flex; align-items:center; justify-content:center; font-size:24px; margin-bottom:14px; }
.ai-card[data-service="openai-gpt"] .ai-card-logo { background:var(--openai-light); }
.ai-card[data-service="google-gemini"] .ai-card-logo { background:var(--gemini-light); }
.ai-card[data-service="anthropic-claude"] .ai-card-logo { background:var(--claude-light); }
.ai-card-name { font-size:20px; font-weight:800; letter-spacing:-0.5px; margin-bottom:4px; }
.ai-card-provider { font-size:13px; color:var(--text-tertiary); font-weight:500; }
.ai-card-body { padding:20px 24px 24px; }
.ai-card-tagline { font-size:13px; font-weight:600; color:var(--text-secondary); margin-bottom:14px; line-height:1.5; }
.ai-card-apis { display:flex; flex-wrap:wrap; gap:5px; margin-bottom:12px; }
.ai-card-api-tag { padding:3px 8px; border-radius:var(--radius-full); font-size:11px; font-weight:600; background:var(--bg-secondary); color:var(--text-secondary); }
.ai-card-api-tag.more { opacity:0.7; }
.ai-card[data-service="openai-gpt"] .ai-card-api-tag { background:var(--openai-light); color:var(--openai); }
.ai-card[data-service="google-gemini"] .ai-card-api-tag { background:var(--gemini-light); color:var(--gemini); }
.ai-card[data-service="anthropic-claude"] .ai-card-api-tag { background:var(--claude-light); color:var(--claude); }
.ai-card-models-preview { display:flex; flex-wrap:wrap; gap:4px; margin-bottom:16px; }
.ai-card-model-chip { padding:2px 8px; border-radius:var(--radius-sm); font-size:10px; font-weight:600; background:var(--bg-secondary); color:var(--text-tertiary); border:1px solid var(--bg-tertiary); }
.ai-card-model-chip.more { border-style:dashed; }
.ai-card-cta { display:flex; align-items:center; gap:8px; font-size:14px; font-weight:600; color:var(--blue); transition:var(--transition); }
.ai-card:hover .ai-card-cta { gap:12px; }

/* ===== Tool Integration Cards ===== */
.tool-cards-grid { display:grid; grid-template-columns:repeat(2,1fr); gap:20px; }
.tool-card { background:var(--bg-card); border-radius:var(--radius-xl); padding:28px; cursor:pointer; transition:var(--transition-slow); border:1.5px solid transparent; }
.tool-card:hover { transform:translateY(-4px); box-shadow:var(--shadow-lg); border-color:var(--blue); }
.tool-card-top { display:flex; align-items:center; gap:14px; margin-bottom:16px; }
.tool-card-icon { width:48px; height:48px; border-radius:var(--radius-md); display:flex; align-items:center; justify-content:center; font-size:24px; flex-shrink:0; }
.tool-card-name { font-size:18px; font-weight:800; letter-spacing:-0.3px; }
.tool-card-category { font-size:12px; color:var(--text-tertiary); font-weight:500; margin-top:2px; }
.tool-card-tagline { font-size:13px; font-weight:600; color:var(--text-secondary); margin-bottom:14px; line-height:1.5; }
.tool-card-apis { display:flex; flex-wrap:wrap; gap:6px; margin-bottom:14px; }
.tool-card-api-tag { padding:4px 10px; border-radius:var(--radius-full); font-size:11px; font-weight:600; }
.tool-card-workflow-preview { display:flex; align-items:center; flex-wrap:wrap; gap:6px; margin-bottom:16px; padding:12px; background:var(--bg-secondary); border-radius:var(--radius-md); }
.tool-step-mini { padding:4px 8px; background:var(--bg-card); border-radius:var(--radius-sm); font-size:11px; font-weight:600; color:var(--text-secondary); border:1px solid var(--bg-tertiary); }
.tool-card-cta { display:flex; align-items:center; gap:8px; font-size:14px; font-weight:600; transition:var(--transition); }
.tool-card:hover .tool-card-cta { gap:12px; }

/* ===== Comparison ===== */
.comparison-section { background:var(--bg-card); border-radius:var(--radius-2xl); padding:48px; }
.comparison-table-wrapper { overflow-x:auto; -webkit-overflow-scrolling:touch; }
.comparison-table { width:100%; border-collapse:separate; border-spacing:0; min-width:700px; }
.comparison-table th, .comparison-table td { padding:16px 20px; text-align:center; font-size:14px; }
.comparison-table thead th { font-weight:700; border-bottom:2px solid var(--bg-secondary); padding-bottom:20px; font-size:15px; }
.comparison-table thead th:first-child { text-align:left; }
.comparison-table tbody td { border-bottom:1px solid var(--bg-secondary); }
.comparison-table tbody td:first-child { text-align:left; font-weight:600; }
.comparison-table tbody tr:last-child td { border-bottom:none; }
.comp-header-badge { padding:6px 14px; border-radius:var(--radius-full); font-size:13px; font-weight:700; white-space:nowrap; }
.comp-header-badge.openai { background:var(--openai-light); color:var(--openai); }
.comp-header-badge.gemini { background:var(--gemini-light); color:var(--gemini); }
.comp-header-badge.claude { background:var(--claude-light); color:var(--claude); }
.comp-category { font-size:13px !important; }
.rating-dots { display:flex; justify-content:center; gap:4px; }
.rating-dot { width:10px; height:10px; border-radius:50%; background:var(--bg-tertiary); transition:var(--transition); }
.rating-dot.filled.openai { background:var(--openai); }
.rating-dot.filled.gemini { background:var(--gemini); }
.rating-dot.filled.claude { background:var(--claude); }
.rating-score { font-size:11px; color:var(--text-tertiary); margin-top:4px; font-weight:600; }

/* ===== Business Expansion ===== */
.expansion-grid { display:grid; grid-template-columns:repeat(2,1fr); gap:16px; }
.expansion-card { background:var(--bg-card); border-radius:var(--radius-lg); padding:28px; transition:var(--transition); }
.expansion-card:hover { box-shadow:var(--shadow-sm); }
.expansion-card-header { display:flex; align-items:center; justify-content:space-between; margin-bottom:16px; }
.expansion-card-category { font-size:17px; font-weight:700; letter-spacing:-0.3px; }
.expansion-level { display:flex; align-items:center; gap:6px; }
.expansion-level-value { font-size:20px; font-weight:800; color:var(--blue); }
.expansion-level-label { font-size:11px; color:var(--text-tertiary); font-weight:500; }
.expansion-bar { height:6px; background:var(--bg-secondary); border-radius:3px; margin-bottom:20px; overflow:hidden; }
.expansion-bar-fill { height:100%; border-radius:3px; background:linear-gradient(90deg, var(--blue) 0%, #8B5CF6 100%); transition:width 1s cubic-bezier(0.4,0,0.2,1); width:0; }
.expansion-before-after { display:grid; grid-template-columns:1fr 1fr; gap:12px; margin-bottom:16px; }
.expansion-state { padding:12px; border-radius:var(--radius-sm); font-size:13px; line-height:1.5; }
.expansion-state.before { background:var(--red-light); color:var(--text-secondary); }
.expansion-state.after { background:var(--green-light); color:var(--text-secondary); }
.expansion-state-label { display:flex; align-items:center; gap:4px; font-size:11px; font-weight:700; text-transform:uppercase; letter-spacing:0.5px; margin-bottom:6px; }
.expansion-state-label i { font-size:10px; }
.expansion-state.before .expansion-state-label { color:var(--red); }
.expansion-state.after .expansion-state-label { color:var(--green); }
.expansion-best-api { font-size:12px; color:var(--text-tertiary); display:flex; align-items:flex-start; gap:6px; line-height:1.5; }
.expansion-best-api i { color:var(--blue); margin-top:2px; }

/* ===== Footer ===== */
.footer { background:var(--bg-dark); color:var(--text-inverse); padding:48px 0 32px; }
.footer-inner { display:flex; justify-content:space-between; align-items:flex-start; margin-bottom:32px; padding-bottom:24px; border-bottom:1px solid rgba(255,255,255,0.1); }
.footer-brand {}
.footer-title { font-size:18px; font-weight:800; margin-bottom:8px; display:flex; align-items:center; gap:8px; }
.footer-title i { color:var(--blue); }
.footer-desc { font-size:14px; color:rgba(255,255,255,0.5); }
.footer-links { display:flex; gap:20px; flex-wrap:wrap; }
.footer-links a { font-size:13px; color:rgba(255,255,255,0.5); text-decoration:none; transition:var(--transition); }
.footer-links a:hover { color:rgba(255,255,255,0.9); }
.footer-copy { font-size:12px; color:rgba(255,255,255,0.25); text-align:center; }

/* ===== Modal ===== */
.modal-overlay { display:none; position:fixed; inset:0; background:rgba(0,0,0,0.4); backdrop-filter:blur(8px); z-index:200; align-items:center; justify-content:center; padding:24px; }
.modal-overlay.active { display:flex; }
.modal { background:var(--bg-card); border-radius:var(--radius-2xl); max-width:800px; width:100%; max-height:85vh; overflow-y:auto; position:relative; animation:modalIn 0.3s ease; }
@keyframes modalIn { from{opacity:0;transform:translateY(20px)} to{opacity:1;transform:translateY(0)} }
.modal-close { position:sticky; top:0; z-index:10; display:flex; justify-content:flex-end; padding:20px 24px 0; background:linear-gradient(180deg, white 60%, transparent); }
.modal-close-btn { width:36px; height:36px; border-radius:var(--radius-full); border:none; background:var(--bg-secondary); cursor:pointer; font-size:16px; color:var(--text-secondary); display:flex; align-items:center; justify-content:center; transition:var(--transition); }
.modal-close-btn:hover { background:var(--bg-tertiary); }
.modal-content { padding:8px 36px 36px; }
.modal-icon { font-size:40px; margin-bottom:16px; }
.modal-title { font-size:28px; font-weight:800; letter-spacing:-0.5px; margin-bottom:4px; }
.modal-subtitle { font-size:14px; color:var(--text-tertiary); font-weight:500; margin-bottom:20px; }
.modal-desc { font-size:15px; color:var(--text-secondary); line-height:1.7; margin-bottom:28px; }
.modal-details { margin-bottom:8px; }
.modal-detail-item { display:flex; padding:14px 0; border-bottom:1px solid var(--bg-secondary); }
.modal-detail-item:last-child { border-bottom:none; }
.modal-detail-label { min-width:120px; font-size:13px; font-weight:700; flex-shrink:0; color:var(--text-primary); }
.modal-detail-value { font-size:13px; color:var(--text-secondary); line-height:1.55; }
.modal-code-label { font-size:12px; font-weight:600; color:var(--text-tertiary); text-transform:uppercase; letter-spacing:0.5px; margin-top:24px; margin-bottom:8px; display:flex; align-items:center; gap:6px; }
.modal-code-label i { font-size:12px; }
.modal-code-block { background:#1E1E2E; border-radius:var(--radius-md); padding:24px; overflow-x:auto; }
.modal-code-block pre { font-family:'JetBrains Mono','Fira Code','SF Mono',monospace; font-size:12.5px; line-height:1.7; color:#CDD6F4; white-space:pre; tab-size:2; }

/* ===== AI Detail Modal ===== */
.ai-detail-header { padding:32px 36px; color:white; position:relative; border-radius:var(--radius-2xl) var(--radius-2xl) 0 0; }
.ai-detail-header.openai { background:linear-gradient(135deg, #10A37F 0%, #0D8C6D 100%); }
.ai-detail-header.gemini { background:linear-gradient(135deg, #4285F4 0%, #3367D6 100%); }
.ai-detail-header.claude { background:linear-gradient(135deg, #D97757 0%, #C4623F 100%); }
.ai-detail-close { position:absolute; top:20px; right:24px; width:36px; height:36px; border-radius:var(--radius-full); border:none; background:rgba(255,255,255,0.2); cursor:pointer; font-size:16px; color:white; display:flex; align-items:center; justify-content:center; transition:var(--transition); }
.ai-detail-close:hover { background:rgba(255,255,255,0.3); }
.ai-detail-logo { font-size:36px; margin-bottom:12px; }
.ai-detail-name { font-size:32px; font-weight:900; letter-spacing:-0.5px; margin-bottom:4px; }
.ai-detail-provider { font-size:14px; opacity:0.8; font-weight:500; }
.ai-detail-tagline { font-size:15px; opacity:0.9; margin-top:8px; font-weight:500; }
.ai-detail-body { padding:32px 36px; }
.ai-detail-section { margin-bottom:36px; }
.ai-detail-section-title { font-size:18px; font-weight:700; margin-bottom:16px; letter-spacing:-0.3px; display:flex; align-items:center; gap:8px; }
.ai-detail-section-title i { font-size:14px; color:var(--text-tertiary); }

/* ===== Tool Detail Modal ===== */
.tool-detail-header { padding:32px 36px; color:white; position:relative; border-radius:var(--radius-2xl) var(--radius-2xl) 0 0; }
.tool-detail-icon { font-size:40px; margin-bottom:12px; }
.tool-detail-pricing { display:inline-flex; align-items:center; gap:6px; margin-top:12px; padding:6px 14px; background:rgba(255,255,255,0.2); border-radius:var(--radius-full); font-size:13px; font-weight:600; }
.tool-detail-pricing i { font-size:11px; }

/* ===== Models ===== */
.model-list { display:flex; flex-direction:column; gap:8px; }
.model-item { display:flex; align-items:center; justify-content:space-between; padding:14px 16px; background:var(--bg-secondary); border-radius:var(--radius-md); gap:12px; }
.model-item-left { min-width:0; }
.model-item-name { font-size:14px; font-weight:700; letter-spacing:-0.2px; }
.model-item-desc { font-size:12px; color:var(--text-tertiary); margin-top:2px; }
.model-item-price { font-size:11px; color:var(--text-tertiary); font-weight:500; white-space:nowrap; text-align:right; flex-shrink:0; }

/* ===== API Capabilities ===== */
.api-capability-list { display:flex; flex-direction:column; gap:12px; }
.api-capability-card { border:1px solid var(--bg-tertiary); border-radius:var(--radius-md); padding:20px; transition:var(--transition); }
.api-capability-card:hover { border-color:var(--blue); box-shadow:0 1px 2px rgba(0,0,0,0.04); }
.api-capability-name { font-size:15px; font-weight:700; margin-bottom:4px; }
.api-capability-desc { font-size:13px; color:var(--text-tertiary); margin-bottom:12px; line-height:1.5; }
.api-capability-tags { display:flex; flex-wrap:wrap; gap:4px; margin-bottom:10px; }
.api-capability-tag { padding:3px 8px; background:var(--blue-light); color:var(--blue); border-radius:var(--radius-full); font-size:11px; font-weight:600; }
.api-capability-use { font-size:12px; color:var(--text-secondary); display:flex; align-items:flex-start; gap:6px; line-height:1.5; }
.api-capability-use i { color:var(--green); margin-top:3px; font-size:10px; }

/* ===== Use Cases ===== */
.usecase-list { display:flex; flex-direction:column; gap:12px; }
.usecase-card { background:var(--bg-secondary); border-radius:var(--radius-md); padding:24px; }
.usecase-title { font-size:16px; font-weight:700; margin-bottom:4px; letter-spacing:-0.2px; }
.usecase-desc { font-size:13px; color:var(--text-secondary); margin-bottom:12px; line-height:1.6; font-weight:600; }
.usecase-details { font-size:13px; color:var(--text-secondary); line-height:1.65; margin-bottom:12px; }
.usecase-impact { display:inline-flex; align-items:center; gap:6px; padding:5px 12px; background:var(--green-light); color:var(--green); border-radius:var(--radius-full); font-size:12px; font-weight:600; }

/* ===== Limits ===== */
.limits-grid { display:grid; grid-template-columns:repeat(3,1fr); gap:12px; }
.limit-card { background:var(--bg-secondary); border-radius:var(--radius-md); padding:16px; text-align:center; }
.limit-label { font-size:11px; color:var(--text-tertiary); font-weight:600; text-transform:uppercase; letter-spacing:0.5px; margin-bottom:6px; }
.limit-value { font-size:13px; font-weight:700; line-height:1.4; }

/* ===== Tabs ===== */
.tab-nav { display:flex; gap:4px; border-bottom:1px solid var(--bg-secondary); margin-bottom:24px; overflow-x:auto; -webkit-overflow-scrolling:touch; }
.tab-btn { padding:10px 16px; border:none; background:none; font-size:14px; font-weight:500; color:var(--text-tertiary); cursor:pointer; border-bottom:2px solid transparent; margin-bottom:-1px; transition:var(--transition); white-space:nowrap; font-family:var(--font); }
.tab-btn:hover { color:var(--text-secondary); }
.tab-btn.active { color:var(--blue); border-bottom-color:var(--blue); font-weight:600; }
.tab-content { display:none; }
.tab-content.active { display:block; }

/* ===== Workflow Steps (Modal) ===== */
.workflow-steps { display:flex; flex-direction:column; gap:0; }
.workflow-step { display:flex; align-items:flex-start; gap:16px; padding:20px 0; border-bottom:1px solid var(--bg-secondary); }
.workflow-step:last-child { border-bottom:none; }
.workflow-step-num { width:32px; height:32px; border-radius:var(--radius-full); color:white; font-size:14px; font-weight:700; display:flex; align-items:center; justify-content:center; flex-shrink:0; }
.workflow-step-action { font-size:15px; font-weight:700; letter-spacing:-0.2px; margin-bottom:4px; }
.workflow-step-detail { font-size:13px; color:var(--text-secondary); line-height:1.6; }

/* ===== Cost Points (Modal) ===== */
.cost-points-list { display:flex; flex-direction:column; gap:12px; }
.cost-point { display:flex; align-items:flex-start; gap:12px; padding:16px; background:var(--bg-secondary); border-radius:var(--radius-md); font-size:14px; color:var(--text-secondary); line-height:1.6; }
.cost-point-num { width:24px; height:24px; border-radius:var(--radius-full); background:var(--blue); color:white; font-size:12px; font-weight:700; display:flex; align-items:center; justify-content:center; flex-shrink:0; }

/* ===== Animations ===== */
.fade-in { opacity:0; transform:translateY(24px); transition:opacity 0.6s ease, transform 0.6s ease; }
.fade-in.visible { opacity:1; transform:translateY(0); }

/* ===== Responsive ===== */
@media (max-width:1024px) {
  .fundamentals-grid { grid-template-columns:repeat(2,1fr); }
  .ai-services-grid { grid-template-columns:repeat(2,1fr); }
  .tool-cards-grid { grid-template-columns:1fr; }
}
@media (max-width:768px) {
  .nav-links { display:none; position:absolute; top:64px; left:0; right:0; background:white; flex-direction:column; padding:12px; border-bottom:1px solid var(--bg-tertiary); box-shadow:var(--shadow-md); gap:4px; }
  .nav-links.mobile-open { display:flex; }
  .nav-mobile-toggle { display:flex; }
  .hero { padding:110px 20px 60px; }
  .hero h1 { font-size:32px; letter-spacing:-0.8px; }
  .hero-desc { font-size:15px; }
  .hero-stats { gap:24px; }
  .hero-stat-value { font-size:28px; }
  .section { padding:60px 0; }
  .section-title { font-size:26px; }
  .fundamentals-grid { grid-template-columns:1fr; }
  .ai-services-grid { grid-template-columns:1fr; }
  .expansion-grid { grid-template-columns:1fr; }
  .cost-grid { grid-template-columns:1fr; }
  .cost-card-versus { grid-template-columns:1fr; gap:8px; }
  .cost-vs-divider { padding:4px 0; }
  .tool-cards-grid { grid-template-columns:1fr; }
  .comparison-section { padding:24px 16px; }
  .modal { max-height:90vh; }
  .modal-content { padding:8px 24px 24px; }
  .modal-title { font-size:22px; }
  .ai-detail-header, .tool-detail-header { padding:24px; }
  .ai-detail-body { padding:24px; }
  .ai-detail-name { font-size:24px; }
  .limits-grid { grid-template-columns:1fr; }
  .expansion-before-after { grid-template-columns:1fr; }
  .footer-inner { flex-direction:column; gap:24px; }
  .footer-links { gap:12px; }
}
@media (max-width:480px) {
  .hero h1 { font-size:28px; }
  .hero-stats { flex-direction:column; gap:16px; }
  .nav-inner { padding:0 16px; }
  .container { padding:0 16px; }
  .modal-overlay { padding:12px; }
  .ai-detail-header, .tool-detail-header { padding:20px; }
  .ai-detail-body { padding:20px; }
}