/* CalcNovaHub AI & Machine Learning category additions.
   Uses existing /assets/shared.css variables and remains self-contained. */
.ai-page{max-width:1280px;margin:0 auto;padding:1.5rem 1.25rem 4rem}
.ai-layout{display:grid;grid-template-columns:minmax(0,1fr) 260px;gap:2rem;align-items:start}
.ai-main{min-width:0;max-width:900px}
.ai-sidebar{position:sticky;top:76px;background:var(--bg-surface);border:1px solid var(--border);border-radius:14px;padding:1rem;max-height:calc(100vh - 100px);overflow:auto}
.ai-sidebar-title{font-size:.72rem;text-transform:uppercase;letter-spacing:.1em;color:var(--text-muted);font-weight:800;margin-bottom:.65rem}
.ai-sidebar a{display:block;padding:.48rem .55rem;border-radius:7px;font-size:.78rem;color:var(--text-secondary);line-height:1.35}
.ai-sidebar a:hover,.ai-sidebar a.active{background:rgba(37,99,235,.09);color:var(--nova-blue)}
.ai-breadcrumb{font-size:.82rem;color:var(--text-muted);margin-bottom:1rem}
.ai-breadcrumb a{color:var(--nova-blue)}
.ai-title{font-size:clamp(1.75rem,4vw,2.4rem);font-weight:800;letter-spacing:-.025em;margin:0 0 .6rem}
.ai-lead{font-size:1rem;color:var(--text-secondary);line-height:1.75;max-width:780px}
.ai-badges{display:flex;gap:.5rem;flex-wrap:wrap;margin:1rem 0 1.5rem}
.ai-badge{font-size:.72rem;font-weight:700;padding:.28rem .65rem;border-radius:999px;background:rgba(37,99,235,.09);color:var(--nova-blue);border:1px solid rgba(37,99,235,.16)}
.ai-calc-card{background:var(--bg-surface);border:1px solid var(--border);border-radius:16px;box-shadow:var(--shadow-sm);overflow:hidden;margin:1.25rem 0 2rem}
.ai-calc-head{padding:1rem 1.25rem;background:linear-gradient(135deg,rgba(37,99,235,.10),rgba(8,145,178,.08));border-bottom:1px solid var(--border)}
.ai-calc-head h2{font-size:1.1rem;margin:0}
.ai-form{padding:1.25rem}
.ai-fields{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:1rem}
.ai-field.full{grid-column:1/-1}
.ai-field label{display:block;font-size:.8rem;font-weight:700;color:var(--text-secondary);margin-bottom:.38rem}
.ai-field input,.ai-field select,.ai-field textarea{width:100%;border:1px solid var(--border);background:var(--bg-elevated);color:var(--text-primary);border-radius:9px;padding:.68rem .78rem;font:inherit}
.ai-field textarea{resize:vertical;min-height:110px;font-family:var(--font-mono);font-size:.82rem;line-height:1.55}
.ai-field input:focus,.ai-field select:focus,.ai-field textarea:focus{outline:0;border-color:var(--nova-blue);box-shadow:0 0 0 3px rgba(37,99,235,.10)}
.ai-help{display:block;font-size:.7rem;color:var(--text-muted);line-height:1.45;margin-top:.3rem}
.ai-actions{display:flex;gap:.7rem;flex-wrap:wrap;margin-top:1.15rem}
.ai-primary,.ai-secondary{border:0;border-radius:9px;padding:.72rem 1.15rem;font-weight:800;cursor:pointer}
.ai-primary{background:var(--nova-grad);color:#fff;min-width:170px}
.ai-secondary{background:var(--bg-elevated);color:var(--text-secondary);border:1px solid var(--border)}
.ai-primary:hover{filter:brightness(1.06);transform:translateY(-1px)}
.ai-error{margin-top:1rem;border:1px solid rgba(220,38,38,.3);background:rgba(220,38,38,.07);color:#b91c1c;padding:.8rem 1rem;border-radius:9px;font-size:.85rem}
.ai-result{margin:0 1.25rem 1.25rem;border:1px solid rgba(5,150,105,.28);background:rgba(5,150,105,.07);border-radius:12px;padding:1.05rem}
.result-kicker{text-transform:uppercase;letter-spacing:.08em;font-size:.65rem;font-weight:800;color:var(--result-green)}
.result-value{font-size:clamp(1.55rem,4vw,2.25rem);font-weight:850;color:var(--result-green);line-height:1.2;margin:.25rem 0}
.result-sub{font-size:.82rem;color:var(--text-secondary);margin-bottom:.75rem}
.result-row{display:flex;justify-content:space-between;gap:1rem;padding:.58rem 0;border-top:1px solid var(--border);font-size:.8rem}
.result-row strong{display:block;color:var(--text-primary)}
.result-row small{display:block;color:var(--text-muted);font-size:.68rem}
.result-row span{font-weight:750;color:var(--text-primary);text-align:right}
.result-note{font-size:.75rem;color:var(--text-muted);line-height:1.55;margin-top:.75rem}
.ai-section{margin:2rem 0}
.ai-section h2{font-size:1.28rem;margin-bottom:.7rem;border-left:4px solid var(--nova-blue);padding-left:.7rem}
.ai-section h3{font-size:1rem;margin:1.1rem 0 .45rem}
.ai-section p,.ai-section li{font-size:.9rem;color:var(--text-secondary);line-height:1.8}
.ai-section ul,.ai-section ol{padding-left:1.25rem}
.ai-formula{background:rgba(37,99,235,.08);border:1px solid rgba(37,99,235,.17);border-left:4px solid var(--nova-blue);padding:1rem 1.1rem;border-radius:0 10px 10px 0;font-family:var(--font-mono);font-size:.84rem;line-height:1.7;overflow-x:auto;color:var(--text-primary)}
.ai-example{background:rgba(245,158,11,.07);border:1px solid rgba(245,158,11,.20);border-radius:11px;padding:1rem 1.1rem}
.ai-callout{background:rgba(8,145,178,.07);border:1px solid rgba(8,145,178,.18);border-radius:11px;padding:1rem 1.1rem}
.ai-mistakes{background:rgba(220,38,38,.05);border:1px solid rgba(220,38,38,.15);border-radius:11px;padding:1rem 1.1rem}
.ai-faq{border:1px solid var(--border);border-radius:11px;margin:.7rem 0;overflow:hidden}
.ai-faq h3{font-size:.9rem;margin:0;padding:.8rem 1rem;background:var(--bg-elevated)}
.ai-faq p{padding:.8rem 1rem;margin:0}
.ai-related{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:.7rem}
.ai-related a{display:flex;justify-content:space-between;gap:.7rem;background:var(--bg-surface);border:1px solid var(--border);border-radius:9px;padding:.75rem .85rem;color:var(--text-primary);font-size:.8rem;font-weight:700}
.ai-related a:hover{border-color:var(--nova-blue);color:var(--nova-blue)}
.ai-method{font-size:.72rem!important;color:var(--text-muted)!important}
.ai-index-hero{background:linear-gradient(135deg,#1d4ed8,#0891b2);border-radius:18px;padding:2.5rem 1.5rem;text-align:center;margin-bottom:2rem}
.ai-index-hero *{color:#fff!important}
.ai-index-hero h1{font-size:clamp(2rem,5vw,2.8rem);font-weight:850;margin:.4rem 0 .6rem}
.ai-index-hero p{max-width:760px;margin:0 auto;line-height:1.75;color:rgba(255,255,255,.93)!important}
.ai-index-count{display:inline-block;margin-top:1rem;background:rgba(255,255,255,.16);border:1px solid rgba(255,255,255,.3);padding:.35rem .85rem;border-radius:999px;font-size:.78rem;font-weight:800}
.ai-group-title{font-size:1.2rem;margin:2rem 0 .8rem}
.ai-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(270px,1fr));gap:.85rem}
.ai-index-card{display:flex;align-items:flex-start;gap:.8rem;background:var(--bg-surface);border:1px solid var(--border);border-radius:11px;padding:1rem;text-decoration:none;transition:.18s}
.ai-index-card:hover{transform:translateY(-2px);border-color:var(--nova-blue);box-shadow:var(--shadow-md)}
.ai-index-icon{font-size:1.35rem}
.ai-index-name{font-size:.9rem;font-weight:800;color:var(--text-primary)}
.ai-index-desc{font-size:.74rem;color:var(--text-secondary);line-height:1.5;margin-top:.25rem}
.ai-index-seo{max-width:900px;margin:3rem auto 0}
@media(max-width:960px){.ai-layout{grid-template-columns:1fr}.ai-sidebar{display:none}.ai-main{max-width:none}}
@media(max-width:650px){.ai-page{padding:1rem .8rem 3rem}.ai-fields{grid-template-columns:1fr}.ai-field.full{grid-column:auto}.ai-related{grid-template-columns:1fr}.ai-form{padding:1rem}.ai-result{margin:0 1rem 1rem}.result-row{align-items:flex-start}.ai-index-hero{padding:2rem 1rem}}
body:not(.light-mode) .ai-error{color:#fca5a5}
body:not(.light-mode) .ai-primary{color:#fff}