:root{--bg:#050814;--bg-secondary:#08101d;--card:#0b1322;--card-hover:#101b2e;--text:#f7fbff;--text-secondary:#aebed0;--muted:#738296;--primary:#133cb4;--primary-dark:#2a0f5c;--primary-light:#b8a2ff;--accent:#5a8bff;--accent-rgb:90,139,255;--accent-dark:#051d6c;--success:#2fbf7f;--danger:#ed6070;--warning:#caa158;--cyan:#22d3ee;--viz-1:#396fc8;--viz-2:#d95926;--viz-3:#199e70;--border:rgba(121, 184, 255, 0.14);--border-light:rgba(164, 184, 255, 0.28);--border-strong:rgba(121, 184, 255, 0.24);--gradient-main:linear-gradient(135deg, #201047 0%, #2b53cf 58%, #4c86f0 100%);--gradient-main-hover:linear-gradient(135deg, #271455 0%, #356adf 58%, #5f95f4 100%);--gradient-hero:linear-gradient(135deg, #340061 0%, #791fcc 50%, #22d3ee 100%);--gradient-card:linear-gradient(180deg, rgba(15, 26, 44, 0.98) 0%, rgba(7, 13, 25, 0.96) 100%);--gradient-success:linear-gradient(135deg, #137445 0%, #005e26 100%);--shadow-sm:0 2px 8px rgba(0, 0, 0, 0.4);--shadow-md:0 4px 16px rgba(0, 0, 0, 0.5);--shadow-lg:0 8px 32px rgba(0, 0, 0, 0.6);--glow-primary:0 0 20px rgba(127, 25, 222, 0.4);--glow-accent:0 0 20px rgba(34, 211, 238, 0.4);--mono:ui-monospace,'SF Mono','Cascadia Mono',Menlo,Consolas,monospace}canvas,img,svg,video{max-width:100%}.card{background:var(--card);border:1px solid var(--border);border-radius:16px;padding:24px;margin-bottom:20px;position:relative;transition:.2s}.card:hover{border-color:rgba(121,184,255,.28)}.card h2{font-size:24px;font-weight:700;margin-bottom:8px;color:var(--text)}.card h3{font-size:14px;font-weight:600;color:var(--muted);margin-bottom:16px}.btn-primary{font-family:inherit;background:var(--gradient-main);color:#fff;border:none;padding:14px 28px;border-radius:12px;font-weight:700;font-size:15px;cursor:pointer;position:relative;overflow:hidden;transition:.3s cubic-bezier(.4, 0, .2, 1);box-shadow:0 4px 16px rgba(35,86,199,.3)}.btn-primary:hover{filter:brightness(1.08)}.btn-primary:active{transform:translateY(0)}.btn-secondary{font-family:inherit;background:0 0;color:var(--text);border:1px solid var(--border);padding:12px 24px;border-radius:10px;font-weight:700;font-size:14px;line-height:1.3;cursor:pointer;transition:border-color .15s,background-color .15s}.btn-secondary:hover{border-color:var(--pw-btn-secondary-hover-border,rgba(121,184,255,.4))}.bubble{max-width:80%;padding:16px 20px;font-size:15px;line-height:1.6;position:relative;animation:.3s cubic-bezier(.2,.8,.2,1) messageSlideIn}.pw-notify{position:fixed;bottom:28px;right:28px;z-index:10000;display:flex;align-items:flex-start;gap:10px;max-width:360px;padding:14px 18px;background:var(--card);border:1px solid var(--border);border-radius:12px;box-shadow:0 12px 40px rgba(0,0,0,.45);color:var(--text);font-size:13.5px;font-weight:600;line-height:1.45;transform:translateY(16px);opacity:0;pointer-events:none;transition:transform .3s cubic-bezier(.34, 1.4, .64, 1),opacity .25s}.pw-notify.show{transform:translateY(0);opacity:1}.pw-notify-icon{flex:0 0 auto;width:18px;height:18px;margin-top:1px}.pw-notify-icon svg{display:block;width:100%;height:100%}.pw-notify.success .pw-notify-icon{color:var(--success)}.pw-notify.error .pw-notify-icon{color:var(--danger)}.pw-notify.info .pw-notify-icon{color:var(--accent)}.pw-notify-msg{flex:1 1 auto;min-width:0}.pw-soft-notice{background:var(--bg);border:1px solid var(--border-strong);border-radius:11px;padding:14px 16px;margin-bottom:12px;font-size:13px;color:var(--text-secondary);display:flex;align-items:center;justify-content:space-between;gap:12px;flex-wrap:wrap}.pw-soft-notice[hidden]{display:none}.pw-soft-notice p{margin:0;flex:1 1 280px;line-height:1.5}.pw-soft-notice strong{color:var(--text)}.pw-soft-notice-actions{display:flex;gap:8px;flex-shrink:0}.pw-soft-notice-btn{padding:6px 10px;font-size:12px;font-weight:600;border-radius:8px;background:0 0;color:var(--text);border:1px solid var(--border-light);box-shadow:none;cursor:pointer}.pw-soft-notice-btn:hover{background:rgba(90,139,255,.1)}.pw-soft-notice-btn.subtle{color:var(--muted);border-color:var(--border)}.pw-soft-notice-btn.subtle:hover{background:0 0;color:var(--text-secondary)}*,::after,::before{box-sizing:border-box;margin:0;padding:0}body,html{height:100%;background:var(--bg);color:var(--text);font-family:'DM Sans',sans-serif;font-size:15px;line-height:1.6;overflow:hidden}button{font-family:inherit}.btn-primary,.btn-secondary{display:inline-flex;align-items:center;justify-content:center;gap:8px;text-decoration:none}#content-area .btn-primary:disabled,#content-area .btn-secondary:disabled{opacity:.45;cursor:default;filter:none}#content-area .btn-primary.is-done,#content-area .btn-primary.is-done:disabled{background:rgba(47,191,127,.12);border:1px solid rgba(47,191,127,.35);box-shadow:none;color:var(--success);opacity:1}#auth-loading{position:fixed;inset:0;background:var(--bg);display:flex;align-items:center;justify-content:center;z-index:9999;transition:opacity .35s}#auth-loading.hidden{opacity:0;pointer-events:none}.auth-loading-inner{display:flex;flex-direction:column;align-items:center;gap:16px;color:var(--text-secondary);font-size:13.5px}.spinner{width:36px;height:36px;border:3px solid var(--border);border-top-color:var(--accent);border-radius:50%;animation:.75s linear infinite spin}@keyframes spin{to{transform:rotate(360deg)}}#topbar{position:fixed;top:0;left:0;right:0;height:58px;background:var(--bg-secondary);border-bottom:1px solid var(--border);display:flex;align-items:center;padding:0 24px;gap:16px;z-index:100}.back-btn{display:flex;align-items:center;gap:7px;padding:7px 13px;background:0 0;border:1px solid var(--border);border-radius:10px;color:var(--text-secondary);font-size:13px;font-weight:600;text-decoration:none;transition:border-color .15s,color .15s;flex-shrink:0}.back-btn:hover{color:var(--text);border-color:rgba(121,184,255,.4)}.topbar-course-name{font-family:'Bricolage Grotesque',sans-serif;font-weight:700;font-size:15px;color:var(--text);flex:1;min-width:0;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.topbar-progress{display:flex;align-items:center;gap:10px;flex-shrink:0}.topbar-pct{font-size:13px;font-weight:700;color:var(--text-secondary);min-width:32px;text-align:right;font-variant-numeric:tabular-nums}.topbar-bar-track{width:110px;height:5px;background:var(--border);border-radius:999px;overflow:hidden}.topbar-bar-fill{height:100%;background:var(--accent);border-radius:999px;transition:width .5s cubic-bezier(.4, 0, .2, 1);width:0%}#app-layout{display:flex;height:100%;padding-top:58px}#sidebar{width:270px;flex-shrink:0;height:100%;overflow-y:auto;background:var(--bg-secondary);border-right:1px solid var(--border);padding:28px 12px 40px}.sidebar-course-title{font-family:'Bricolage Grotesque',sans-serif;font-size:16px;font-weight:700;color:var(--text);margin:0 12px 4px}.sidebar-course-desc,.sidebar-course-points{font-size:12.5px;color:var(--muted);line-height:1.5;margin:0 12px}.sidebar-course-points{margin-top:8px}.sidebar-divider{height:1px;background:var(--border);margin:20px 12px 16px}.lessons-label{font-size:12.5px;font-weight:600;color:var(--muted);margin:0 12px 8px}.lesson-row{display:flex;align-items:flex-start;gap:12px;padding:10px 12px;border-radius:10px;cursor:pointer;transition:background-color .15s,color .15s;margin-bottom:2px}.lesson-row:hover{background:rgba(255,255,255,.05)}.lesson-num{width:22px;height:22px;border-radius:50%;border:1px solid var(--border-strong);display:flex;align-items:center;justify-content:center;font-size:11px;font-weight:700;color:var(--muted);flex-shrink:0;margin-top:1px}.lesson-row.completed .lesson-num{border-color:var(--success);color:var(--success)}.lesson-row.active .lesson-num{border-color:var(--accent);color:var(--accent)}.lesson-row-title{font-size:13.5px;line-height:1.45;color:var(--text-secondary)}.lesson-row.active .lesson-row-title{color:var(--text);font-weight:600}.lesson-row.completed .lesson-row-title{color:var(--muted)}.lesson-row.quiz-row{margin-top:8px}#content-area{flex:1;height:100%;overflow-y:auto;padding:52px 60px 80px}#content-area>*{max-width:680px;margin-left:auto;margin-right:auto}#quiz-view,#results-view{display:none}.lesson-title{font-family:'Bricolage Grotesque',sans-serif;font-size:32px;font-weight:800;color:var(--text);line-height:1.2;margin-bottom:28px}.lesson-body{font-size:16px;line-height:1.75;color:var(--text-secondary);margin-bottom:40px}.lesson-body p{margin-bottom:18px}.lesson-body p:last-child{margin-bottom:0}.lesson-body strong{color:var(--text);font-weight:700}.lesson-body h3{font-family:'Bricolage Grotesque',sans-serif;font-size:18px;font-weight:700;color:var(--text);line-height:1.35;margin:32px 0 10px}.lesson-body ol,.lesson-body ul{padding-left:22px;margin-bottom:18px}.lesson-body li{margin-bottom:8px}.lesson-body code{background:rgba(255,255,255,.08);padding:2px 6px;border-radius:4px;font-size:.9em}.pw-lex{margin-bottom:40px;padding:24px;background:var(--card);border:1px solid var(--border);border-radius:16px}.pw-lex-subhead{font-family:'Bricolage Grotesque',sans-serif;font-size:16px;font-weight:700;color:var(--text);margin:24px 0 14px}.pw-lex-subhead:first-child{margin-top:0}.pw-lex-grid{display:grid;grid-template-columns:1fr 1fr;gap:14px;margin-bottom:18px}.pw-lex-field label{display:block;font-size:12.5px;font-weight:600;color:var(--text-secondary);margin-bottom:6px}.pw-lex-field input{width:100%;background:var(--bg-secondary);border:1px solid var(--border);border-radius:10px;padding:10px 12px;color:var(--text);font-family:inherit;font-size:14px;transition:border-color .15s,box-shadow .15s}.pw-lex-field input:focus{outline:0;border-color:var(--accent);box-shadow:0 0 0 3px rgba(var(--accent-rgb),.25)}.pw-lex-results{display:flex;flex-direction:column;gap:8px;padding-top:14px;border-top:1px solid var(--border)}.pw-lex-row{display:flex;justify-content:space-between;align-items:baseline;font-size:14px;color:var(--text-secondary)}.pw-lex-row strong{color:var(--text);font-size:15px;font-weight:700;font-variant-numeric:tabular-nums}.pw-lex-row-total strong{font-size:18px}.pw-lex-note{font-size:12.5px;color:var(--muted);line-height:1.5;margin-top:12px}.action-footer{display:flex;align-items:stretch;gap:12px;padding-top:32px;border-top:1px solid var(--border);flex-wrap:wrap}.action-footer-meta{align-self:center;margin-left:auto;font-size:12.5px;color:var(--muted)}.quiz-intro{font-size:15px;color:var(--text-secondary);margin-bottom:32px;line-height:1.7}.quiz-q{margin-bottom:32px}.quiz-q-text{font-family:'Bricolage Grotesque',sans-serif;font-size:16px;font-weight:700;color:var(--text);line-height:1.4;margin-bottom:12px}.quiz-opt{display:flex;align-items:center;gap:12px;width:100%;text-align:left;margin:8px 0;padding:12px 16px;border:1px solid var(--border);border-radius:10px;background:var(--card);color:var(--text-secondary);cursor:pointer;font:inherit;font-size:14px;transition:border-color .15s,background-color .15s,color .15s}.quiz-opt:hover{border-color:rgba(121,184,255,.28);color:var(--text)}.quiz-opt.selected{border-color:var(--accent);background:rgba(var(--accent-rgb),.08);color:var(--text)}.quiz-opt-letter{width:22px;height:22px;border-radius:50%;border:1px solid var(--border-strong);flex-shrink:0;display:flex;align-items:center;justify-content:center;font-size:11px;font-weight:700;color:var(--muted)}.quiz-opt.selected .quiz-opt-letter{border-color:var(--accent);color:var(--accent)}.results-hero{margin-bottom:24px;padding:28px 24px;background:var(--card);border:1px solid var(--border);border-radius:16px;text-align:center}.results-score{font-family:'Bricolage Grotesque',sans-serif;font-size:40px;font-weight:800;line-height:1.1;margin-bottom:8px;font-variant-numeric:tabular-nums}.results-label{font-size:15px;font-weight:600;color:var(--text-secondary)}.results-review-item{margin-bottom:12px;padding:20px 24px;border-radius:16px;border:1px solid var(--border);background:var(--card)}.results-review-q{font-weight:700;color:var(--text);margin-bottom:8px;font-size:14px;line-height:1.45}.results-review-your{font-size:13.5px;margin-bottom:4px}.results-review-your.correct{color:var(--success)}.results-review-your.wrong{color:var(--danger)}.results-review-correct{font-size:13.5px;color:var(--success);margin-bottom:8px}.results-review-explain{font-size:13.5px;color:var(--text-secondary);line-height:1.6}#results-view .action-footer{margin-top:32px}#course-complete-screen{display:none;flex-direction:column;align-items:center;justify-content:center;text-align:center;height:100%;padding:48px 0;animation:.5s fadeUp}@keyframes fadeUp{from{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}.complete-trophy{display:flex;align-items:center;justify-content:center;margin-bottom:20px;color:var(--accent)}.complete-title{font-family:'Bricolage Grotesque',sans-serif;font-size:32px;font-weight:800;color:var(--text);line-height:1.2;margin-bottom:10px}.complete-points,.complete-subtitle{font-size:15px;color:var(--text-secondary);max-width:440px;line-height:1.6}.complete-points{margin-top:4px}#course-complete-screen .btn-primary{margin-top:32px}#error-screen{display:none;flex-direction:column;align-items:center;justify-content:center;text-align:center;height:100%;padding:48px 0}.error-icon{color:var(--muted);margin-bottom:16px;opacity:.25}.error-title{font-family:'Bricolage Grotesque',sans-serif;font-size:18px;font-weight:700;color:var(--text);margin-bottom:8px}.error-msg{font-size:14px;color:var(--muted);max-width:400px;line-height:1.6;margin-bottom:28px}::-webkit-scrollbar{width:12px;height:12px}::-webkit-scrollbar-track{background:var(--bg);border-radius:10px}::-webkit-scrollbar-thumb{background:var(--bg-secondary);border-radius:10px;border:3px solid var(--bg)}::-webkit-scrollbar-thumb:hover{background:var(--border)}@media (max-width:768px){#topbar{padding:0 12px;gap:8px}.topbar-course-name{font-size:13px}.topbar-bar-track{width:60px}body,html{overflow:auto;height:auto}#app-layout{flex-direction:column}#content-area{order:1;padding:28px 16px 48px;height:auto;overflow-y:visible}#sidebar{order:2;width:100%;height:auto;border-right:none;border-top:1px solid var(--border);padding:24px 4px 40px}.lesson-title{font-size:26px;margin-bottom:20px}.lesson-body{font-size:15px}.pw-lex{padding:20px}.pw-lex-grid{grid-template-columns:1fr}.action-footer .btn-primary{order:3;flex:1 1 100%}}