:root{--primary-100: #f3f6fc;--primary-90: #e5ebf8;--primary-80: #d2ddf8;--primary-70: #c2d1f5;--primary-60: #9ebbff;--primary-50: #85a9ff;--primary-40: #6693ff;--primary-30: #477eff;--primary-20: #2465ff;--primary-base: #0a53ff;--primary-tint-10: #0049f5;--primary-tint-20: #0043e0;--primary-tint-30: #003dcc;--primary-tint-40: #0739b0;--primary-tint-50: #07339d;--primary-tint-60: #062d89;--primary-tint-70: #052778;--primary-tint-80: #0a2461;--primary-tint-90: #06163c;--neutral-100: #f7f7f8;--neutral-90: #edeef0;--neutral-80: #e2e4e8;--neutral-70: #d7dbdf;--neutral-60: #c7cdd6;--neutral-50: #b8c0cc;--neutral-40: #a6b0bf;--neutral-30: #94a1b2;--neutral-20: #8291a5;--neutral-base: #718199;--neutral-tint-10: #64748b;--neutral-tint-20: #5e6d83;--neutral-tint-30: #556377;--neutral-tint-40: #4e596a;--neutral-tint-50: #454f5e;--neutral-tint-60: #3d4552;--neutral-tint-70: #353d48;--neutral-tint-80: #2e343d;--neutral-tint-90: #1d2026;--bg: var(--neutral-100);--text: var(--neutral-tint-90);--muted: var(--neutral-base);--card-bg: #ffffff;--border: var(--neutral-80);--shadow-rgb: 29, 32, 38;--white: #ffffff;--black: #000000;--accent: var(--primary-base);--accent-2: var(--primary-tint-20);--accent-soft: var(--primary-100);--easy: #16a34a;--medium: #d97706;--hard: #dc2626;--easy-soft: #dcfce7;--medium-soft: #fef3c7;--hard-soft: #fee2e2;--group-general: var(--primary-60);--group-uiux: var(--primary-base);--group-frontend: var(--neutral-tint-10);--group-interviews: #7c3aed;--group-ai: #0d9488;--group-general-soft: #eef2ff;--group-uiux-soft: var(--primary-100);--group-frontend-soft: #eef1f4;--group-interviews-soft: #f3e8ff;--group-ai-soft: #e3f7f4;--radius: 14px;--sidebar-w: 272px;--topbar-h: 60px;--container-w: 1200px}*{box-sizing:border-box}html,body{margin:0;padding:0}.material-symbols-outlined{font-family:Material Symbols Outlined;font-weight:400;font-style:normal;line-height:1;letter-spacing:normal;text-transform:none;white-space:nowrap;word-wrap:normal;direction:ltr;-webkit-font-smoothing:antialiased;font-feature-settings:"liga";font-variation-settings:"FILL" 0,"wght" 400,"GRAD" 0,"opsz" 20;display:inline-block}body{font-family:Inter,system-ui,-apple-system,Segoe UI,Roboto,sans-serif;background:var(--bg);color:var(--text);-webkit-font-smoothing:antialiased}a{color:inherit}#app{display:flex;flex-direction:column;min-height:100vh}.app-body{display:flex;flex:1;align-items:flex-start;max-width:var(--container-w);margin:0 auto;width:100%}.topbar{position:sticky;top:0;z-index:50;background:var(--card-bg);border-bottom:1px solid var(--border)}.topbar-inner{display:flex;align-items:center;gap:8px;height:var(--topbar-h);padding:0 24px;max-width:var(--container-w);margin:0 auto}.topbar-brand{display:flex;align-items:center;gap:10px;flex-shrink:0;text-decoration:none;color:var(--text);margin-right:28px}.topbar-brand-badge{width:28px;height:28px;border-radius:8px;background:linear-gradient(135deg,var(--accent),var(--accent-2));display:flex;align-items:center;justify-content:center;font-size:12.5px;font-weight:800;color:#fff;flex-shrink:0}.topbar-brand-text{font-weight:800;font-size:14.5px;letter-spacing:-.1px}.topbar-tabs{display:flex;align-items:center;gap:2px;height:100%;flex:1;overflow-x:auto}.topbar-tabs::-webkit-scrollbar{display:none}.topbar-tab{display:flex;align-items:center;height:100%;padding:0 4px;margin-right:24px;font-size:13.5px;font-weight:600;color:var(--muted);text-decoration:none;border-bottom:2px solid transparent;white-space:nowrap;transition:color .15s ease,border-color .15s ease}.topbar-tab:last-child{margin-right:0}.topbar-tab:hover,.topbar-tab.active{color:var(--text)}.topbar-tab--interview.active{border-bottom-color:var(--group-interviews)}.topbar-tab--ui-ux-design.active{border-bottom-color:var(--group-uiux)}.topbar-tab--frontend.active{border-bottom-color:var(--group-frontend)}.topbar-tab--ai.active{border-bottom-color:var(--group-ai)}.topbar-menu-btn{display:none;flex-shrink:0;width:36px;height:36px;border-radius:9px;border:1px solid var(--border);background:#fff;align-items:center;justify-content:center;cursor:pointer}.topbar-menu-btn span,.topbar-menu-btn span:before,.topbar-menu-btn span:after{content:"";display:block;width:16px;height:2px;background:var(--text);border-radius:2px;position:relative}.topbar-menu-btn span:before{position:absolute;top:-5px}.topbar-menu-btn span:after{position:absolute;top:5px}.sidebar{width:var(--sidebar-w);flex-shrink:0;position:sticky;top:var(--topbar-h);align-self:flex-start;height:calc(100vh - var(--topbar-h));display:flex;flex-direction:column;background:var(--bg);border-right:1px solid var(--border);overflow:hidden}.search-wrap{padding:16px 16px 8px}.search-input{width:100%;padding:9px 12px 9px 32px;border-radius:9px;border:1px solid var(--border);background:var(--card-bg);color:var(--text);font-size:13px;font-family:inherit;background-image:url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='14' height='14' viewBox='0 0 24 24' fill='none' stroke='%2394a1b2' stroke-width='2'><circle cx='11' cy='11' r='7'/><line x1='21' y1='21' x2='16.65' y2='16.65'/></svg>");background-repeat:no-repeat;background-position:11px center}.search-input::placeholder{color:var(--muted)}.search-input:focus{outline:none;border-color:var(--accent)}.nav{flex:1;overflow-y:auto;padding:10px 12px 24px}.nav::-webkit-scrollbar{width:6px}.nav::-webkit-scrollbar-thumb{background:var(--border);border-radius:99px}.nav-section{margin-top:24px}.nav-section:first-child{margin-top:8px}.nav-section-title{font-size:11px;font-weight:700;text-transform:uppercase;letter-spacing:.5px;color:var(--muted);padding:0 12px;margin-bottom:6px}.nav-section-items{display:flex;flex-direction:column}.nav-link{display:flex;align-items:center;justify-content:space-between;gap:10px;padding:12px;margin:0 -1px;border-radius:8px;border-left:2px solid transparent;font-size:13.5px;color:var(--text);text-decoration:none}.nav-link:hover{background:var(--neutral-90)}.nav-link.active{background:var(--accent);color:var(--white);font-weight:700;border-left-color:var(--accent)}.nav-link-icon{font-size:18px;color:var(--muted);flex-shrink:0}.nav-link.active .nav-link-icon{color:var(--white)}.nav-link-label{flex:1;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.nav-link-count{font-size:10.5px;color:var(--muted);flex-shrink:0}.nav-link.active .nav-link-count{color:var(--white)}.overlay{display:none;position:fixed;top:0;right:0;bottom:0;left:0;top:var(--topbar-h);background:rgba(var(--shadow-rgb),.5);z-index:44}.overlay.show{display:block}.content{flex:1;min-width:0;padding:32px 32px 100px;max-width:920px}.content-header{margin-bottom:30px}.breadcrumb{font-size:12.5px;color:var(--muted);margin-bottom:10px;display:flex;gap:6px;align-items:center}.content-title{font-size:26px;font-weight:800;margin:0 0 8px;letter-spacing:-.3px}.content-desc{font-size:14.5px;color:var(--muted);line-height:1.6;max-width:640px}.level-badge{display:inline-flex;align-items:center;gap:6px;font-size:11.5px;font-weight:700;padding:4px 10px;border-radius:99px;text-transform:uppercase;letter-spacing:.4px}.badge-easy{background:var(--easy-soft);color:#15803d}.badge-medium{background:var(--medium-soft);color:#b45309}.badge-hard{background:var(--hard-soft);color:#b91c1c}.badge-general{background:var(--group-general-soft);color:var(--group-general)}.badge-ui-ux-design{background:var(--group-uiux-soft);color:var(--group-uiux)}.badge-frontend-development,.badge-frontend{background:var(--group-frontend-soft);color:var(--group-frontend)}.badge-interviews,.badge-interview{background:var(--group-interviews-soft);color:var(--group-interviews)}.badge-ai{background:var(--group-ai-soft);color:var(--group-ai)}.q-card{background:var(--card-bg);border:1px solid var(--border);border-radius:var(--radius);padding:24px 26px;margin-bottom:18px;box-shadow:0 1px 2px rgba(var(--shadow-rgb),.05);scroll-margin-top:24px}.q-head{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:12px}.q-num{font-family:JetBrains Mono,monospace;font-size:12px;font-weight:600;color:#fff;background:linear-gradient(135deg,var(--accent),var(--accent-2));border-radius:8px;padding:4px 8px;flex-shrink:0}.q-title{font-size:16.5px;font-weight:700;line-height:1.45;margin:0 0 14px}.q-check{display:flex;align-items:center;gap:6px;font-size:11.5px;color:var(--muted);flex-shrink:0;cursor:pointer;-webkit-user-select:none;user-select:none;white-space:nowrap}.q-check input{width:15px;height:15px;accent-color:var(--accent);cursor:pointer}.q-card.done{border-color:#bbf7d0;background:#f7fdf9}.q-row{margin-bottom:11px;font-size:13.8px;line-height:1.65}.q-row:last-child{margin-bottom:0}.q-label{display:block;font-weight:700;color:var(--text);margin-bottom:4px}.q-row.sample{background:var(--accent-soft);border-radius:10px;padding:12px 14px;margin-top:14px}.q-row.sample .q-label{color:var(--accent)}.q-row .q-val{color:var(--neutral-tint-30)}.q-row.sample .q-val{color:#333a5c;font-style:italic}.hidden{display:none!important}.empty-state{text-align:center;padding:80px 20px;color:var(--muted)}.empty-state h3{color:var(--text);font-size:17px}.content-nav-btns{display:flex;justify-content:space-between;gap:14px;margin-top:32px;padding-top:24px;border-top:1px solid var(--border)}.nav-btn{display:flex;flex-direction:column;gap:2px;padding:12px 16px;border-radius:10px;border:1px solid var(--border);background:#fff;cursor:pointer;font-family:inherit;text-align:left;max-width:48%;font-size:12.5px;color:var(--muted)}.nav-btn:hover{border-color:var(--accent);background:var(--accent-soft)}.nav-btn .lbl{font-weight:700;color:var(--text);font-size:13.5px}.nav-btn.next{text-align:right;margin-left:auto}mark{background:#fde68a;color:inherit;border-radius:3px;padding:0 2px}.card-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:16px;margin-top:10px}.info-card{background:var(--card-bg);border:1px solid var(--border);border-radius:var(--radius);padding:20px 22px;text-align:left;cursor:pointer;font-family:inherit;text-decoration:none;display:block;color:inherit}.info-card:hover{border-color:var(--accent)}.info-card h3{margin:12px 0 6px;font-size:16px;color:var(--text)}.info-card p{margin:0;color:var(--muted);font-size:13px;line-height:1.5}.guide-content{max-width:720px}.guide-section{margin-bottom:40px}.guide-section:last-child{margin-bottom:0}.guide-section h2{font-size:19px;font-weight:800;margin:0 0 14px;letter-spacing:-.2px}.guide-section p{font-size:14.5px;line-height:1.75;color:var(--text);margin:0 0 14px}.guide-section p:last-child{margin-bottom:0}.guide-list{margin:0 0 14px;padding-left:20px}.guide-list.bullet{list-style:disc}.guide-list.numbered{list-style:decimal}.guide-list li{font-size:14.5px;line-height:1.7;color:var(--text);margin-bottom:6px}.guide-section code,.guide-list code{font-family:JetBrains Mono,monospace;font-size:.9em;background:var(--bg);border:1px solid var(--border);border-radius:4px;padding:1px 5px}.diagram-panel{border:1px solid var(--border);border-radius:var(--radius);background:var(--card-bg);padding:20px 22px;margin:18px 0 22px}.diagram-panel__title{font-size:11.5px;font-weight:800;text-transform:uppercase;letter-spacing:.4px;color:var(--muted);margin-bottom:14px}.diagram-panel__body{display:flex;justify-content:center;align-items:center;overflow-x:auto}.diagram-panel__caption{font-size:12.5px;color:var(--muted);margin-top:14px;line-height:1.6;text-align:center}.checklist-panel{border:1px solid var(--border);border-radius:var(--radius);background:var(--card-bg);padding:18px 20px;margin:14px 0 22px}.checklist-panel__title{font-size:12.5px;font-weight:800;margin-bottom:12px;color:var(--text)}.checklist-item{display:flex;align-items:flex-start;gap:10px;font-size:13.8px;line-height:1.55;color:var(--text);margin-bottom:10px}.checklist-item:last-child{margin-bottom:0}.checklist-item__mark{width:18px;height:18px;border-radius:6px;background:var(--accent-soft);color:var(--accent);display:flex;align-items:center;justify-content:center;flex-shrink:0;margin-top:1px;font-size:11px;font-weight:800}.code-diff{border:1px solid var(--border);border-radius:var(--radius);overflow:hidden;margin:14px 0 22px;font-family:JetBrains Mono,monospace;font-size:12.3px}.code-diff__row{padding:14px 18px;white-space:pre-wrap;line-height:1.6;border-bottom:1px solid var(--border)}.code-diff__row:last-child{border-bottom:none}.code-diff__row.old{background:var(--hard-soft);color:#7f1d1d}.code-diff__row.new{background:var(--easy-soft);color:#14532d}.code-diff__label{display:block;font-family:Inter,sans-serif;font-size:10.5px;font-weight:800;text-transform:uppercase;letter-spacing:.4px;margin-bottom:6px;opacity:.7}.comparison-panel{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:14px;margin:14px 0 22px}.comparison-panel__side{border-radius:var(--radius);padding:16px 18px;font-size:13.5px;line-height:1.6}.comparison-panel__side.weak,.comparison-panel__side.old{background:var(--hard-soft);border:1px solid #fecaca;color:#7f1d1d}.comparison-panel__side.strong,.comparison-panel__side.new{background:var(--easy-soft);border:1px solid #bbf7d0;color:#14532d}.comparison-panel__side.neutral{background:var(--bg);border:1px solid var(--border);color:var(--text)}.comparison-panel__label{display:block;font-size:10.5px;font-weight:800;text-transform:uppercase;letter-spacing:.4px;margin-bottom:8px;opacity:.75}.comparison-panel__side code{display:block;font-family:JetBrains Mono,monospace;font-size:14px}.stat-compare{display:flex;flex-direction:column;gap:12px}.stat-compare__row{display:grid;grid-template-columns:140px 1fr auto;align-items:center;gap:12px;font-size:12.5px}.stat-compare__label{color:var(--muted);font-weight:600}.stat-compare__track{height:10px;border-radius:99px;background:var(--border);overflow:hidden}.stat-compare__fill{height:100%;border-radius:99px;background:linear-gradient(90deg,var(--accent),var(--accent-2))}.stat-compare__value{font-weight:700;color:var(--text);font-variant-numeric:tabular-nums}.timeline{display:flex;flex-direction:column;position:relative;padding-left:26px}.timeline:before{content:"";position:absolute;left:5px;top:6px;bottom:6px;width:2px;background:var(--border)}.timeline-step{position:relative;padding-bottom:20px}.timeline-step:last-child{padding-bottom:0}.timeline-step:before{content:"";position:absolute;left:-26px;top:2px;width:13px;height:13px;border-radius:50%;background:var(--accent);border:3px solid var(--accent-soft)}.timeline-step__label{font-size:10.5px;font-weight:800;text-transform:uppercase;letter-spacing:.4px;color:var(--accent);margin-bottom:4px}.timeline-step__text{font-size:13.5px;line-height:1.6;color:var(--text)}.heuristic-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(130px,1fr));gap:18px 14px;width:100%}.heuristic-grid__item{display:flex;flex-direction:column;align-items:center;text-align:center;gap:10px}.heuristic-grid__badge{width:38px;height:38px;border-radius:50%;flex-shrink:0;display:flex;align-items:center;justify-content:center;background:var(--accent-soft);color:var(--accent);font-weight:800;font-size:14px}.heuristic-grid__label{font-size:12.3px;font-weight:600;color:var(--text);line-height:1.4}.quadrant-grid{display:grid;grid-template-columns:1fr 1fr;grid-template-rows:1fr 1fr;gap:2px;background:var(--border);border:1px solid var(--border);border-radius:var(--radius);overflow:hidden;min-height:220px}.quadrant-grid__cell{background:var(--card-bg);padding:14px 16px;display:flex;flex-direction:column;justify-content:center}.quadrant-grid__title{font-size:12.5px;font-weight:800;margin-bottom:4px;color:var(--text)}.quadrant-grid__text{font-size:11.5px;color:var(--muted);line-height:1.5}.data-flow{display:flex;align-items:center;gap:10px;flex-wrap:wrap;justify-content:center}.data-flow__col{display:flex;flex-direction:column;gap:8px;align-items:center}.data-flow__box{border:1.5px solid var(--border);border-radius:10px;background:var(--bg);padding:10px 16px;font-size:12.5px;font-weight:700;color:var(--text);text-align:center;min-width:90px}.data-flow__box.accent{border-color:var(--accent);background:var(--accent-soft);color:var(--accent)}.data-flow__arrow{color:var(--muted);font-size:16px;flex-shrink:0}.shape-demo{display:flex;gap:22px;flex-wrap:wrap;justify-content:center;align-items:flex-start;padding:6px}.shape-demo__group{display:flex;gap:6px;padding:12px;border-radius:10px}.shape-demo__group.grouped{background:var(--accent-soft)}.shape-demo__dot{width:16px;height:16px;border-radius:50%;background:var(--neutral-40);flex-shrink:0}.shape-demo__dot.accent{background:var(--accent)}.islands-grid{display:grid;grid-template-columns:repeat(4,1fr);grid-auto-rows:44px;gap:6px;max-width:320px;margin:0 auto}.islands-grid__cell{border-radius:6px;background:var(--border)}.islands-grid__cell.island{background:var(--accent);position:relative;display:flex;align-items:center;justify-content:center;font-size:14px}.book-card,.course-card{background:var(--card-bg);border:1px solid var(--border);border-radius:var(--radius);padding:18px 20px}.book-card__title,.course-card__title{font-size:14.5px;font-weight:700;margin:0 0 4px;color:var(--text)}.book-card__meta,.course-card__meta{font-size:12px;color:var(--accent);font-weight:600;margin-bottom:8px}.book-card__desc,.course-card__desc{font-size:12.8px;color:var(--muted);line-height:1.55;margin:0}.prompt-card{border:1px solid var(--border);border-radius:var(--radius);overflow:hidden;margin:14px 0 22px}.prompt-card__prompt{background:var(--neutral-tint-90);color:var(--neutral-60);padding:16px 18px;font-family:JetBrains Mono,monospace;font-size:12.5px;line-height:1.7;white-space:pre-wrap}.prompt-card__annotations{padding:14px 18px;display:flex;flex-direction:column;gap:8px}.prompt-card__annotation{display:flex;gap:10px;font-size:12.5px;line-height:1.6;color:var(--text)}.prompt-card__annotation b{color:var(--accent);flex-shrink:0}.set-progress{margin:18px 0 26px;max-width:420px}.set-progress__label{display:flex;justify-content:space-between;font-size:12px;color:var(--muted);margin-bottom:7px}.set-progress__label b{color:var(--text);font-weight:700}.set-progress__bar{height:6px;border-radius:99px;background:var(--border);overflow:hidden}.set-progress__fill{height:100%;background:linear-gradient(90deg,var(--accent),var(--accent-2));transition:width .3s ease}.bottom-nav{display:none}@media (max-width: 900px){.topbar-inner{gap:6px;padding:0 14px}.topbar-brand{margin-right:16px}.topbar-brand-text{display:none}.topbar-menu-btn{display:flex}.topbar-tabs{display:none}.sidebar{position:fixed;top:var(--topbar-h);left:0;width:100%;height:calc(100vh - var(--topbar-h));z-index:55;background:var(--card-bg);box-shadow:0 10px 30px rgba(var(--shadow-rgb),.15);transform:translate(-100%);transition:transform .25s ease}.sidebar.open{transform:translate(0)}.content{padding:32px 20px 110px}.bottom-nav{display:flex;position:fixed;left:0;right:0;bottom:0;z-index:46;background:var(--card-bg);border-top:1px solid var(--border);padding-bottom:env(safe-area-inset-bottom)}.bottom-nav-item{flex:1;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:2px;padding:8px 4px 10px;color:var(--muted);text-decoration:none}.bottom-nav-icon{font-size:22px}.bottom-nav-label{font-size:10.5px;font-weight:600}.bottom-nav-item.active{color:var(--accent)}}@media (max-width: 640px){.comparison-panel{grid-template-columns:1fr}.islands-grid{max-width:260px}}