:root{--bg:#f6f8fb;--surface:#fff;--surface-2:#f0f3f8;--text:#172033;--muted:#647086;--border:#dfe5ee;--accent:#e41f2b;--accent-2:#a80f18;--critical:#c91924;--high:#b36500;--info:#1769aa;--success:#18794e;--radius:18px;--shadow:0 18px 55px rgba(29,42,67,.12);--max:1240px;color-scheme:light}
:root[data-theme="dark"]{--bg:#0d1119;--surface:#151b26;--surface-2:#1c2432;--text:#eef3fb;--muted:#9ba8bb;--border:#2b3647;--accent:#ff4752;--accent-2:#ff7b82;--critical:#ff6d75;--high:#ffc369;--info:#71b7ff;--success:#66d49d;color-scheme:dark}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:24px}body{margin:0;background:var(--bg);color:var(--text);font:16px/1.7 Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif}a{color:inherit}.container{width:min(calc(100% - 36px),var(--max));margin:auto}.skip-link{position:absolute;top:-80px;left:16px;background:#fff;color:#000;padding:10px;z-index:99}.skip-link:focus{top:12px}.brand{display:flex;align-items:center;gap:11px;text-decoration:none;font-weight:850;letter-spacing:-.02em}.brand__mark{display:grid;place-items:center;width:39px;height:39px;border-radius:12px;background:var(--accent);color:#fff;font-size:.78rem}.icon-button{border:1px solid var(--border);background:var(--surface);color:var(--text);width:42px;height:42px;border-radius:12px;cursor:pointer;font-size:1.1rem}.home-hero,.site-header{background:radial-gradient(circle at 80% 0,#29354d 0,transparent 38%),linear-gradient(135deg,#0b101b,#192336);color:#fff}.home-hero{padding-bottom:58px}.home-nav,.header-row{display:flex;align-items:center;justify-content:space-between;min-height:74px}.home-nav .icon-button,.site-header .icon-button{background:rgba(255,255,255,.07);color:#fff;border-color:rgba(255,255,255,.16)}.header-actions{display:flex;gap:9px}.home-hero__content{display:grid;grid-template-columns:minmax(0,1fr) 330px;gap:62px;align-items:end;padding:82px 0 38px}.eyebrow{display:inline-block;color:#ff9ea4;font-size:.76rem;font-weight:900;letter-spacing:.14em;text-transform:uppercase}.eyebrow--dark{color:var(--accent)}h1,h2,h3{line-height:1.2;letter-spacing:-.035em}.home-hero h1{font-size:clamp(3rem,7vw,6rem);line-height:.96;margin:.18em 0;max-width:850px}.home-hero p{max-width:760px;color:#d3dbea;font-size:1.08rem}.hero-actions{display:flex;gap:12px;margin-top:28px}.button{display:inline-flex;align-items:center;justify-content:center;padding:12px 18px;border-radius:11px;text-decoration:none;font-weight:850}.button--primary{background:var(--accent);color:#fff}.button--ghost{border:1px solid rgba(255,255,255,.22);color:#fff}.overall-progress,.progress-card{padding:23px;border:1px solid rgba(255,255,255,.14);border-radius:18px;background:rgba(255,255,255,.065);backdrop-filter:blur(10px)}.overall-progress strong,.progress-card strong{display:block;font-size:2.35rem;margin:4px 0 12px}.overall-progress small,.progress-card small{display:block;color:#bdc8d9;margin-top:10px}.progress-bar{height:9px;background:rgba(127,140,160,.25);border-radius:999px;overflow:hidden}.progress-bar span{display:block;height:100%;width:0;background:linear-gradient(90deg,var(--accent),#ff7c84);transition:width .25s}.global-search,.module-controls input,.module-controls select{width:100%;padding:15px 17px;border:1px solid var(--border);border-radius:13px;background:var(--surface);color:var(--text);font:inherit}.global-search{border-color:rgba(255,255,255,.15);background:rgba(255,255,255,.08);color:#fff}.global-search::placeholder{color:#bdc8d9}.home-main{padding:38px 0 90px}.value-strip{display:grid;grid-template-columns:repeat(4,1fr);gap:1px;background:var(--border);border:1px solid var(--border);border-radius:16px;overflow:hidden;margin-bottom:72px}.value-strip div{padding:20px;background:var(--surface)}.value-strip strong,.value-strip span{display:block}.value-strip span{color:var(--muted);font-size:.88rem}.section-heading{display:flex;justify-content:space-between;align-items:end;gap:40px;margin-bottom:24px}.section-heading h2{font-size:clamp(2rem,4vw,3.5rem);margin:.15em 0}.section-heading p{max-width:520px;color:var(--muted)}.topic-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}.topic-card{display:block;padding:24px;border:1px solid var(--border);border-top:5px solid var(--info);border-radius:var(--radius);background:var(--surface);text-decoration:none;box-shadow:0 7px 20px rgba(18,31,53,.04);transition:.18s}.topic-card:hover{transform:translateY(-4px);box-shadow:var(--shadow)}.topic-card.priority-critical{border-top-color:var(--critical)}.topic-card.priority-high{border-top-color:var(--high)}.topic-card__head{display:flex;justify-content:space-between;align-items:center}.topic-progress{font-size:.82rem;color:var(--muted);font-weight:850}.topic-card h2{margin:22px 0 5px;font-size:1.45rem}.topic-card p{margin:0;color:var(--text);font-weight:800}.topic-description{display:block;margin-top:12px;color:var(--muted);font-size:.9rem}.badge{display:inline-flex;padding:5px 9px;border-radius:999px;font-size:.7rem;font-weight:900;text-transform:uppercase;letter-spacing:.055em;background:var(--surface-2);color:var(--muted)}.badge--critical{background:#fff0f0;color:var(--critical)}.badge--high{background:#fff6e7;color:var(--high)}.badge--level{color:var(--info)}.badge--importance{color:var(--critical)}:root[data-theme="dark"] .badge--critical,:root[data-theme="dark"] .badge--high{background:var(--surface-2)}.principles{margin-top:84px}.principles h2{font-size:2.2rem}.principles-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}.principles article{padding:24px;border:1px solid var(--border);border-radius:16px;background:var(--surface)}.principles article>strong{font-size:2rem;color:var(--accent)}.principles p{color:var(--muted)}.layout{display:grid;grid-template-columns:248px minmax(0,1fr);gap:32px;padding:34px 0 90px}.sidebar{position:sticky;top:20px;align-self:start;max-height:calc(100vh - 40px);overflow:auto;padding:18px;border:1px solid var(--border);border-radius:17px;background:var(--surface)}.sidebar__header{display:flex;justify-content:space-between;align-items:center;margin-bottom:15px}.topic-nav{display:grid;gap:5px}.topic-nav a{padding:9px 10px;border-radius:9px;text-decoration:none;color:var(--muted);font-size:.91rem;font-weight:720}.topic-nav a:hover,.topic-nav a.is-active{background:var(--surface-2);color:var(--accent)}.content{min-width:0}.topic-hero{display:grid;grid-template-columns:minmax(0,1fr) 260px;gap:32px;align-items:end;padding:38px;border:1px solid var(--border);border-top:5px solid var(--info);border-radius:22px;background:var(--surface)}.topic-hero.priority-critical{border-top-color:var(--critical)}.topic-hero h1{font-size:clamp(3rem,6vw,5.2rem);margin:.12em 0}.topic-hero p{max-width:750px;color:var(--muted);font-size:1.05rem}.hero-tags,.kicker,.reading-lanes,.related-links{display:flex;flex-wrap:wrap;gap:8px}.hero-tags span,.reading-lanes span,.related-links span,.related-links a{padding:5px 9px;border-radius:8px;background:var(--surface-2);color:var(--muted);font-size:.78rem;font-weight:750;text-decoration:none}.progress-card{background:var(--surface-2);border-color:var(--border)}.progress-card small{color:var(--muted)}.module-controls{display:grid;grid-template-columns:1fr 210px;gap:12px;margin:20px 0}.chapter-toc{display:flex;gap:8px;align-items:center;overflow:auto;padding:15px;border:1px solid var(--border);border-radius:13px;background:var(--surface);white-space:nowrap}.chapter-toc strong{margin-right:8px}.chapter-toc a{padding:5px 9px;border-radius:8px;background:var(--surface-2);color:var(--muted);text-decoration:none;font-size:.82rem;font-weight:750}.callout{padding:17px 19px;border-radius:13px;margin:20px 0}.callout--info{background:color-mix(in srgb,var(--info) 10%,var(--surface));border-left:4px solid var(--info)}.concept-list{display:grid;gap:24px}.concept-card{padding:30px;border:1px solid var(--border);border-radius:19px;background:var(--surface);box-shadow:0 8px 25px rgba(18,31,53,.035)}.concept-card__top{display:grid;grid-template-columns:minmax(0,1fr) 150px;gap:25px}.concept-card h2{font-size:clamp(1.9rem,4vw,2.7rem);margin:.25em 0}.concept-card h3{font-size:1.23rem;margin:1.6em 0 .4em}.concept-lead{font-size:1.04rem;color:var(--muted)}.stars{color:#d58a00;letter-spacing:.06em}.status-control{display:flex;flex-direction:column;gap:7px}.status-control label{font-size:.77rem;text-transform:uppercase;font-weight:850;color:var(--muted);letter-spacing:.07em}.status-control select{padding:10px;border:1px solid var(--border);border-radius:10px;background:var(--surface-2);color:var(--text)}.status-control small{color:var(--muted)}.reading-lanes{padding:13px 0;border-bottom:1px solid var(--border);margin-bottom:6px}.concept-card ul{padding-left:1.2rem}.concept-card pre{overflow:auto;padding:20px;border:1px solid #2b3548;border-radius:13px;background:#111722;color:#eef4ff;line-height:1.55}.concept-card code{font-family:"SFMono-Regular",Consolas,monospace}.output-box{display:flex;gap:14px;align-items:center;padding:12px 15px;border-radius:10px;background:var(--surface-2)}.output-box code{white-space:pre-line}.warning-box{padding:12px 18px;border-left:4px solid var(--critical);border-radius:10px;background:color-mix(in srgb,var(--critical) 8%,var(--surface))}.interview-box{padding:20px;border:1px solid color-mix(in srgb,var(--accent) 35%,var(--border));border-radius:14px;background:color-mix(in srgb,var(--accent) 5%,var(--surface))}.interview-box .question{font-size:1.12rem;font-weight:850}.interview-box details{border-top:1px solid var(--border);padding:10px 0}.interview-box summary{cursor:pointer;font-weight:850}.followup{margin-top:12px;padding:12px;border-radius:10px;background:var(--surface-2)}.concept-actions{display:flex;justify-content:space-between;gap:12px;align-items:center;margin-top:22px;padding-top:18px;border-top:1px solid var(--border)}.concept-actions button{border:0;border-radius:10px;background:var(--accent);color:#fff;padding:10px 13px;font-weight:850;cursor:pointer}.concept-actions a{color:var(--muted);font-size:.86rem}.page-nav{display:flex;justify-content:space-between;gap:16px;margin-top:26px}.page-nav a{font-weight:850;text-decoration:none}.is-hidden{display:none!important}.focus-mode .sidebar,.focus-mode .site-header,.focus-mode .module-controls,.focus-mode .chapter-toc,.focus-mode .page-nav{display:none}.focus-mode .layout{display:block}.focus-mode .content{max-width:900px;margin:auto}.mobile-only{display:none}
@media(max-width:980px){.topic-grid{grid-template-columns:repeat(2,1fr)}.home-hero__content,.topic-hero{grid-template-columns:1fr}.layout{grid-template-columns:1fr}.sidebar{position:fixed;inset:0 auto 0 0;width:290px;max-height:none;z-index:30;border-radius:0;transform:translateX(-105%);transition:.2s}.sidebar.is-open{transform:translateX(0)}.mobile-only{display:inline-grid;place-items:center}.value-strip{grid-template-columns:repeat(2,1fr)}}
@media(max-width:680px){.container{width:min(calc(100% - 24px),var(--max))}.topic-grid,.principles-grid,.value-strip{grid-template-columns:1fr}.home-hero__content{padding-top:48px}.section-heading{display:block}.concept-card{padding:21px}.concept-card__top,.module-controls{grid-template-columns:1fr}.hero-actions{flex-direction:column}.topic-hero{padding:25px}.concept-actions{align-items:flex-start;flex-direction:column}}

/* Interactive interview examples */
.reveal-button{display:inline-flex;align-items:center;justify-content:center;margin-top:12px;padding:10px 14px;border:0;border-radius:10px;background:var(--accent);color:#fff;font:inherit;font-weight:850;cursor:pointer}.reveal-button:hover{filter:brightness(.96)}.reveal-button:focus-visible{outline:3px solid color-mix(in srgb,var(--accent) 35%,transparent);outline-offset:3px}.reveal-button--secondary{background:var(--surface-2);color:var(--text);border:1px solid var(--border)}.example-reveal{margin-top:12px}.example-explanation{margin-top:14px;padding:16px 18px;border-left:4px solid var(--info);border-radius:10px;background:color-mix(in srgb,var(--info) 7%,var(--surface))}.example-explanation h3{margin-top:0}.reveal-button[hidden],.example-reveal[hidden],.example-explanation[hidden]{display:none!important}

/* Version 1: collapsible handbook navigation */
.topic-nav__root{display:block;padding:10px;border-radius:9px;text-decoration:none;color:var(--muted);font-size:.91rem;font-weight:760}
.topic-nav__root:hover{background:var(--surface-2);color:var(--accent)}
.nav-group{border:1px solid var(--border);border-radius:11px;background:var(--surface-2);overflow:hidden}
.nav-group summary{cursor:pointer;padding:10px 11px;font-weight:850;color:var(--accent);list-style:none}
.nav-group summary::-webkit-details-marker{display:none}
.nav-group summary::after{content:'▾';float:right;transition:transform .18s}
.nav-group:not([open]) summary::after{transform:rotate(-90deg)}
.nav-group__links{display:grid;gap:2px;padding:0 6px 7px}
.nav-group__links a{padding:7px 8px;font-size:.82rem;line-height:1.35}
.nav-group__links a.is-current{background:var(--surface);color:var(--accent)}
@media(max-width:980px){.nav-group__links a{padding:9px 8px}}