/* ============ RESET & VARIABLES ============ */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
:root{
  --bg:#ffffff;--bg2:#f7f8fc;--bg3:#eef0f7;
  --surface:#ffffff;--surface2:#f2f3f9;
  --border:#e2e4ef;--border2:#d0d3e3;
  --text:#1a1c2e;--text2:#5a5d78;--text3:#8b8ea6;
  --accent:#4f46e5;--accent2:#6366f1;--accent-light:#eef2ff;
  --green:#059669;--green-light:#ecfdf5;
  --orange:#d97706;--orange-light:#fffbeb;
  --red:#dc2626;--red-light:#fef2f2;
  --cyan:#0891b2;
  --radius:14px;--radius-lg:20px;--radius-sm:10px;
  --font:'Inter','Noto Sans TC',sans-serif;
  --mono:'JetBrains Mono',monospace;
  --shadow:0 1px 3px rgba(0,0,0,.06),0 4px 16px rgba(0,0,0,.04);
  --shadow-lg:0 4px 12px rgba(0,0,0,.06),0 12px 40px rgba(0,0,0,.06);
}
html{scroll-behavior:smooth;font-size:16px}
body{font-family:var(--font);background:var(--bg2);color:var(--text);line-height:1.7;overflow-x:hidden}
a{color:inherit;text-decoration:none}

/* ============ HERO ============ */
#hero{position:relative;min-height:80vh;display:flex;align-items:center;justify-content:center;padding:80px 24px;overflow:hidden;background:linear-gradient(160deg,#f0f4ff 0%,#e8f5e9 50%,#f3e8ff 100%);max-width:100%}
.hero-bg-grid{position:absolute;inset:0;background-image:linear-gradient(rgba(0,0,0,.04) 1px,transparent 1px),linear-gradient(90deg,rgba(0,0,0,.04) 1px,transparent 1px);background-size:48px 48px;opacity:.6}
.hero-glow{position:absolute;border-radius:50%;filter:blur(100px);opacity:.3;pointer-events:none}
.g1{width:500px;height:500px;background:#818cf8;top:-15%;left:-5%}
.g2{width:400px;height:400px;background:#34d399;bottom:-10%;right:-5%}
.hero-content{text-align:center;position:relative;z-index:2;max-width:760px}
.hero-badge{display:inline-flex;align-items:center;gap:8px;background:white;border:1px solid var(--border);padding:6px 18px;border-radius:999px;font-size:.82rem;color:var(--accent);font-weight:600;margin-bottom:28px;box-shadow:var(--shadow)}
.badge-dot{width:8px;height:8px;border-radius:50%;background:var(--green);animation:pulse-dot 2s infinite}
@keyframes pulse-dot{0%,100%{opacity:1}50%{opacity:.4}}
h1{font-size:clamp(2rem,5vw,3.4rem);font-weight:800;line-height:1.2;letter-spacing:-.02em}
.line1{display:block;color:var(--text)}
.line2{display:block;background:linear-gradient(135deg,var(--accent),var(--green),var(--cyan));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.hero-sub{color:var(--text2);font-size:1.1rem;margin-top:22px;line-height:1.8}
.hero-sub strong{color:var(--text);font-weight:600}

/* ============ SECTIONS ============ */
section{padding:80px 24px;max-width:900px;margin:0 auto}
.section-header{text-align:center;margin-bottom:52px}
.section-tag{display:inline-block;font-size:.72rem;font-weight:700;text-transform:uppercase;letter-spacing:.12em;color:var(--accent);background:var(--accent-light);padding:5px 16px;border-radius:999px;margin-bottom:14px}
.section-header h2{font-size:clamp(1.6rem,3.5vw,2.2rem);font-weight:800}
.section-header p{color:var(--text2);margin-top:8px;font-size:1rem}

/* ============ NARRATIVE INTRO ============ */
.narrative{max-width:720px}
.n-block h2{font-size:1.8rem;font-weight:800;margin-bottom:20px}
.n-lead{font-size:1.08rem;color:var(--text2);line-height:2}
.n-lead strong{color:var(--text);font-weight:600}

/* ============ FEATURE STORIES ============ */
.feature-story{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-lg);padding:36px;margin-bottom:24px;box-shadow:var(--shadow);transition:transform .3s,box-shadow .3s;display:flex;gap:28px;align-items:flex-start}
.feature-story:hover{transform:translateY(-2px);box-shadow:var(--shadow-lg)}
.fs-number{font-family:var(--mono);font-size:2.4rem;font-weight:800;color:var(--accent-light);line-height:1;min-width:48px;color:var(--accent);opacity:.2}
.fs-content{flex:1}
.fs-content h3{font-size:1.3rem;font-weight:700;margin-bottom:10px}
.fs-desc{color:var(--text2);font-size:.95rem;line-height:1.8}
.fs-desc strong{color:var(--text);font-weight:600}

/* Chat Demo */
.fs-demo{margin-top:20px;background:var(--bg2);border-radius:var(--radius);padding:20px;border:1px solid var(--border)}
.chat-bubble{padding:12px 16px;border-radius:16px;font-size:.9rem;max-width:85%;line-height:1.6;margin-bottom:10px}
.chat-bubble:last-child{margin-bottom:0}
.chat-bubble.user{background:var(--accent);color:white;margin-left:auto;border-bottom-right-radius:4px;text-align:right}
.chat-bubble.bot{background:white;border:1px solid var(--border);border-bottom-left-radius:4px;box-shadow:0 1px 4px rgba(0,0,0,.04)}
.bot-label{display:block;font-size:.72rem;font-weight:700;color:var(--accent);margin-bottom:6px}
.chat-bubble.bot small{color:var(--text3);font-size:.78rem}

/* Feature Highlights */
.fs-highlights{display:flex;flex-wrap:wrap;gap:8px;margin-top:18px}
.fs-highlights span{font-size:.76rem;padding:4px 12px;border-radius:999px;background:var(--accent-light);color:var(--accent);font-weight:600}

/* Permission Tiers */
.permission-tiers{display:flex;align-items:center;justify-content:center;gap:12px;margin-top:24px;flex-wrap:wrap}
.tier{text-align:center;padding:20px 24px;background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);min-width:160px}
.tier-icon{font-size:2rem;margin-bottom:6px}
.tier-label{font-weight:700;font-size:1rem;color:var(--accent);margin-bottom:4px}
.tier-desc{font-size:.82rem;color:var(--text2);line-height:1.5}
.tier-desc small{color:var(--text3)}
.tier-arrow{font-size:1.4rem;color:var(--text3);font-weight:300}

/* ============ RAG SECTION ============ */
#rag{max-width:900px;background:var(--surface);border-radius:var(--radius-lg);padding:60px 40px;margin:0 auto 40px;border:1px solid var(--border);box-shadow:var(--shadow-lg)}
.rag-story{display:grid;grid-template-columns:1fr 1fr;gap:20px;margin-bottom:48px}
.rag-problem,.rag-solution{padding:28px;border-radius:var(--radius);line-height:1.8}
.rag-problem{background:var(--red-light);border:1px solid #fecaca}
.rag-solution{background:var(--green-light);border:1px solid #bbf7d0}
.rag-problem h3,.rag-solution h3{font-size:1.1rem;margin-bottom:10px}
.rag-problem p,.rag-solution p{font-size:.92rem;color:var(--text2)}
.rag-problem strong{color:var(--red)}
.rag-solution strong{color:var(--green)}

/* RAG Visual Steps */
.rag-visual-step{margin-bottom:40px}
.rag-visual-step h3{font-size:1.2rem;font-weight:700;margin-bottom:12px;color:var(--accent)}
.rag-explain{font-size:.95rem;color:var(--text2);line-height:1.9;margin-bottom:20px}
.rag-explain strong{color:var(--text);font-weight:600}

/* Diagram: Embed (Step 1) */
.diagram-embed{background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius-lg);padding:32px 20px;overflow-x:auto}
.diagram-row{display:flex;align-items:center;justify-content:center;gap:12px;min-width:500px}
.dia-box{text-align:center;padding:20px 18px;border-radius:var(--radius);border:1px solid var(--border);background:white;min-width:160px;flex:1}
.dia-icon{font-size:2rem;margin-bottom:6px}
.dia-label{font-weight:700;font-size:.95rem;margin-bottom:4px}
.dia-sub{font-size:.78rem;color:var(--text3);line-height:1.4}
.dia-nums{font-family:var(--mono);font-size:.82rem;color:var(--accent);margin:6px 0}
.dia-arrow{font-size:1.6rem;color:var(--text3);font-weight:300;flex-shrink:0}
.dia-doc{border-color:#93c5fd;background:#eff6ff}
.dia-ai{border-color:#c4b5fd;background:#f5f3ff}
.dia-db{border-color:#6ee7b7;background:#ecfdf5}

/* Vector Example Map */
.vector-example{margin-top:28px;background:white;border:1px solid var(--border);border-radius:var(--radius);padding:24px}
.vector-example h4{font-size:1rem;font-weight:700;margin-bottom:8px;color:var(--accent)}
.vector-example>p{font-size:.88rem;color:var(--text2);margin-bottom:16px}
.vector-map{position:relative;margin-bottom:16px}
.vmap-axis-y{writing-mode:vertical-rl;text-orientation:mixed;font-size:.7rem;color:var(--text3);position:absolute;left:-4px;top:50%;transform:translateY(-50%) rotate(180deg);letter-spacing:.05em}
.vmap-area{position:relative;margin-left:24px;height:320px;background:linear-gradient(135deg,#f8faff,#f0fdf8);border:1px solid var(--border);border-radius:var(--radius-sm);overflow:hidden}
.vmap-dot{position:absolute;display:flex;align-items:center;gap:6px;z-index:2}
.dot-circle{width:12px;height:12px;border-radius:50%;flex-shrink:0;box-shadow:0 0 6px rgba(0,0,0,.15)}
.dot-circle.blue{background:#3b82f6}
.dot-circle.green{background:#22c55e}
.dot-circle.orange{background:#f59e0b}
.dot-text{font-size:.75rem;font-weight:600;line-height:1.3;white-space:nowrap}
.dot-coord{font-family:var(--mono);font-size:.68rem;color:var(--text3);font-weight:400}
.vmap-cluster{position:absolute;font-size:.72rem;font-weight:600;color:var(--text3);z-index:1}
.vmap-highlight{position:absolute;border:2px dashed #93c5fd;border-radius:12px;background:rgba(59,130,246,.04);z-index:0}
.vmap-axis-x{text-align:center;font-size:.7rem;color:var(--text3);margin-top:6px;margin-left:24px}
.vector-insight{background:linear-gradient(135deg,#eef2ff,#fef9c3);border:1px solid #e0e7ff;border-radius:var(--radius-sm);padding:16px;font-size:.88rem;color:var(--text2);line-height:1.7}
.vector-insight strong{color:var(--text)}

/* Dimension Explainer */
.dim-explainer{margin-top:20px;background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);padding:24px}
.dim-explainer h4{font-size:1rem;font-weight:700;margin-bottom:8px}
.dim-explainer>p{font-size:.88rem;color:var(--text2);margin-bottom:16px;line-height:1.6}
.dim-progression{display:grid;grid-template-columns:1fr 1fr 1fr 2fr;gap:12px;margin-bottom:16px}
.dim-card{text-align:center;padding:16px 12px;background:white;border:1px solid var(--border);border-radius:var(--radius-sm)}
.dim-card-big{border-color:var(--accent);border-width:2px;background:linear-gradient(135deg,#eef2ff,#f0fdf4)}
.dim-num{font-weight:800;font-size:1rem;color:var(--accent);margin-bottom:8px}
.dim-card-big .dim-num{font-size:1.2rem}
.dim-visual{margin-bottom:8px;min-height:36px;display:flex;align-items:center;justify-content:center}
.dim-line{width:80%;height:3px;background:linear-gradient(to right,var(--text3),var(--accent));border-radius:2px;display:flex;justify-content:space-between;align-items:center;position:relative;padding:0 2px}
.dim-line span{font-size:.6rem;color:var(--text3);position:relative;top:-10px}
.dim-grid{display:grid;grid-template-columns:1fr 1fr;gap:4px}
.dim-grid span{font-size:.7rem;color:var(--accent)}
.dim-cube{font-size:1.8rem}
.dim-mega{font-size:.95rem;font-weight:700;color:var(--accent)}
.dim-desc{font-size:.78rem;color:var(--text2);line-height:1.4}
.dim-desc small{font-size:.72rem;color:var(--text3)}
.dim-desc small strong{color:var(--accent)}
.dim-bottom{text-align:center;font-size:.88rem;color:var(--text2);line-height:1.7;padding:14px;background:white;border-radius:var(--radius-sm);border:1px solid var(--border)}
.dim-bottom strong{color:var(--accent)}

/* Diagram: Compare (Step 2) */
.diagram-compare{display:grid;grid-template-columns:1fr auto 1fr;gap:16px;align-items:stretch}
.dia-compare-side{text-align:center;padding:24px 20px;border-radius:var(--radius-lg);border:2px solid}
.dia-bad{border-color:#fca5a5;background:#fef2f2}
.dia-good{border-color:#86efac;background:#f0fdf4}
.dia-compare-badge{font-weight:700;font-size:1rem;margin-bottom:14px}
.dia-search-box{display:inline-block;background:white;border:1px solid var(--border);border-radius:var(--radius-sm);padding:8px 16px;font-size:.9rem;font-weight:500;margin-bottom:8px}
.dia-compare-arrow{font-size:1.2rem;color:var(--text3);margin:6px 0}
.dia-result-miss,.dia-result-hit{margin:8px 0}
.dia-file{display:inline-block;padding:10px 20px;border-radius:var(--radius-sm);font-weight:600;font-size:.95rem}
.dia-file.miss{background:#fee2e2;color:#991b1b;opacity:.5;text-decoration:line-through}
.dia-file.hit{background:#dcfce7;color:#166534;border:2px solid #86efac}
.dia-miss-label{color:var(--red);font-weight:700;font-size:.88rem;margin-top:4px}
.dia-hit-label{color:var(--green);font-weight:700;font-size:.88rem;margin-top:4px}
.dia-compare-side p{font-size:.82rem;color:var(--text2);margin-top:10px;line-height:1.5}
.dia-compare-vs{align-self:center;font-weight:800;font-size:1.1rem;color:var(--text3)}

/* Diagram: Flow (Step 3) */
.diagram-flow{display:flex;align-items:stretch;gap:8px}
.flow-card{flex:1;text-align:center;padding:20px 14px;border-radius:var(--radius);border:2px solid;position:relative}
.fc-num{position:absolute;top:-12px;left:50%;transform:translateX(-50%);width:26px;height:26px;border-radius:50%;color:white;font-size:.75rem;font-weight:700;display:flex;align-items:center;justify-content:center}
.fc-icon{font-size:1.8rem;margin:8px 0 6px}
.fc-title{font-weight:700;font-size:.88rem;margin-bottom:4px}
.fc-desc{font-size:.78rem;color:var(--text2);line-height:1.4}
.flow-connector{align-self:center;font-size:1.3rem;color:var(--text3);flex-shrink:0}
.fc-blue{border-color:#93c5fd;background:#eff6ff}.fc-blue .fc-num{background:#3b82f6}
.fc-purple{border-color:#c4b5fd;background:#f5f3ff}.fc-purple .fc-num{background:#8b5cf6}
.fc-green{border-color:#86efac;background:#f0fdf4}.fc-green .fc-num{background:#22c55e}
.fc-teal{border-color:#5eead4;background:#f0fdfa}.fc-teal .fc-num{background:#14b8a6}
.flow-bottom-note{text-align:center;margin-top:20px;padding:14px 20px;background:linear-gradient(135deg,#eef2ff,#ecfdf5);border-radius:var(--radius);font-size:.9rem;color:var(--text2);line-height:1.6}
.flow-bottom-note strong{color:var(--accent);font-weight:700}

/* Why AI */
.rag-why-ai{margin-top:48px;padding:32px;background:linear-gradient(135deg,#eef2ff,#f0fdf4);border:1px solid var(--border);border-radius:var(--radius-lg)}
.rag-why-ai h3{font-size:1.2rem;font-weight:700;text-align:center;margin-bottom:24px}
.why-ai-points{display:flex;flex-direction:column;gap:20px}
.why-point{display:flex;gap:16px;align-items:flex-start}
.why-icon{font-size:1.6rem;min-width:36px;text-align:center;margin-top:2px}
.why-point strong{display:block;font-size:1rem;margin-bottom:6px}
.why-point p{font-size:.88rem;color:var(--text2);line-height:1.8;margin:0}
.why-point em{display:block;margin-top:8px;color:var(--accent);font-style:normal;font-weight:600;font-size:.85rem}

/* Knowledge Base Grid */
.rag-kb{margin-top:48px}
.rag-kb h3{font-size:1.2rem;font-weight:700;text-align:center;margin-bottom:24px}
.kb-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:12px}
.kb-item{display:flex;flex-direction:column;align-items:center;gap:6px;padding:20px 16px;background:var(--bg2);border:1px solid var(--border);border-radius:var(--radius);text-align:center;transition:transform .2s}
.kb-item:hover{transform:translateY(-2px)}
.kb-icon{font-size:1.6rem}
.kb-item strong{font-size:.88rem}
.kb-item small{font-size:.75rem;color:var(--text3)}

/* ============ SUMMARY ============ */
#summary{max-width:900px;padding:40px 24px 80px}
.summary-card{background:linear-gradient(135deg,#eef2ff,#ecfdf5);border:1px solid var(--border);border-radius:var(--radius-lg);padding:48px;text-align:center;box-shadow:var(--shadow)}
.summary-card h2{font-size:1.8rem;font-weight:800;margin-bottom:14px}
.summary-card>p{color:var(--text2);font-size:1rem;line-height:1.8;margin-bottom:32px}
.skills-overview{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;margin-top:28px}
.so-item{display:flex;align-items:center;gap:8px;padding:10px 14px;background:white;border:1px solid var(--border);border-radius:var(--radius-sm);font-size:.85rem;font-weight:600;transition:transform .2s}
.so-item:hover{transform:translateY(-2px)}
.so-item span{font-size:1.2rem}

/* ============ FOOTER ============ */
footer{padding:28px;text-align:center;border-top:1px solid var(--border);color:var(--text3);font-size:.82rem;background:white}
.footer-inner{max-width:900px;margin:0 auto}
.footer-inner span{font-weight:600;color:var(--text2);display:block;margin-bottom:4px}

/* ============ ANIMATIONS ============ */
.fade-in{opacity:0;transform:translateY(20px);transition:opacity .5s ease,transform .5s ease}
.fade-in.visible{opacity:1;transform:translateY(0)}

/* ============ RESPONSIVE ============ */
@media(max-width:768px){
  .feature-story{flex-direction:column;gap:12px;padding:24px}
  .fs-number{font-size:1.6rem}
  .rag-story{grid-template-columns:1fr}
  .rag-explain br{display:none}
  .diagram-row{flex-direction:column;min-width:0}
  .dia-arrow{transform:rotate(90deg)}
  .diagram-compare{grid-template-columns:1fr;gap:12px}
  .dia-compare-vs{padding:4px 0}
  .diagram-flow{flex-direction:column;align-items:center}
  .flow-card{width:100%;max-width:280px}
  .flow-connector{transform:rotate(90deg)}
  .dim-progression{grid-template-columns:1fr 1fr}
  .dim-card-big{grid-column:span 2}
  .kb-grid{grid-template-columns:repeat(2,1fr)}
  .skills-overview{grid-template-columns:repeat(2,1fr)}
  .permission-tiers{flex-direction:column}
  .tier-arrow{transform:rotate(90deg)}
  #rag{padding:36px 20px;margin:0 16px 40px}
  .hero-sub br{display:none}
  .n-lead br{display:none}
}