:root{--primary:#4318ff;--primary-hover:#31c;--primary-light:#eff4fb;--primary-subtle:#e9edf7;--secondary:#2b3674;--text-dark:#1b2559;--text-muted:#707eae;--text-light:#a3aed0;--bg-page:#f4f7fe;--bg-card:#fff;--bg-hover:#f8fafc;--success:#05cd99;--success-light:#e6fbf5;--success-border:#a7f3d0;--danger:#ee5d50;--danger-light:#feeceb;--danger-border:#fecaca;--warning:#ffb547;--warning-light:#fff7eb;--info:#0075ff;--info-light:#ebf5ff;--subject-maths:#4318ff;--subject-english:#05cd99;--subject-vr:#ffb547;--subject-nvr:#805ad5;--radius-sm:8px;--radius-md:14px;--radius-lg:20px;--radius-xl:28px;--shadow-sm:0 2px 6px #707eae14;--shadow-md:0 8px 24px #707eae1f;--shadow-lg:0 16px 40px #707eae2e;--shadow-glow:0 6px 20px #4318ff59;--font-family:"Plus Jakarta Sans", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;--transition:all .22s cubic-bezier(.4, 0, .2, 1)}*{box-sizing:border-box;-webkit-tap-highlight-color:transparent;margin:0;padding:0}body{font-family:var(--font-family);background-color:var(--bg-page);color:var(--text-dark);-webkit-user-select:none;user-select:none;flex-direction:column;min-height:100vh;font-size:16px;line-height:1.5;display:flex;overflow-x:hidden}button,input,select{font-family:inherit}.app-container{flex-direction:column;flex:1;width:100%;max-width:1100px;margin:0 auto;padding:16px 20px 48px;display:flex}.top-navbar{background:var(--bg-card);border-radius:var(--radius-xl);box-shadow:var(--shadow-sm);z-index:40;border:1px solid #e2e8f0cc;justify-content:space-between;align-items:center;margin-bottom:24px;padding:12px 24px;display:flex;position:sticky;top:12px}.brand-wrapper{cursor:pointer;align-items:center;gap:12px;display:flex}.brand-icon{background:linear-gradient(135deg, var(--primary) 0%, #2b3674 100%);color:#fff;width:44px;height:44px;box-shadow:var(--shadow-glow);border-radius:12px;flex-shrink:0;justify-content:center;align-items:center;font-size:19px;font-weight:900;display:flex}.brand-text h1{letter-spacing:-.02em;color:var(--secondary);font-size:19px;font-weight:800;line-height:1.15}.brand-text .subtext{color:var(--text-muted);letter-spacing:.04em;text-transform:uppercase;font-size:11px;font-weight:700}.nav-actions{align-items:center;gap:10px;display:flex}.pill-badge{background:var(--primary-light);color:var(--primary);border:1px solid var(--primary-subtle);border-radius:9999px;align-items:center;gap:6px;padding:6px 14px;font-size:13px;font-weight:700;display:inline-flex}.pill-badge.streak{background:var(--warning-light);color:#d97706;border-color:#fde68a}.pill-badge.offline-status{background:var(--success-light);color:#047857;border-color:var(--success-border)}.pill-badge.offline-status.is-offline{background:var(--warning-light);color:#b45309;border-color:#fcd34d}.status-dot{background-color:var(--success);border-radius:50%;width:8px;height:8px}.is-offline .status-dot{background-color:var(--warning);animation:1.6s infinite pulseDot}@keyframes pulseDot{0%,to{opacity:1}50%{opacity:.4}}.icon-btn{background:var(--bg-page);cursor:pointer;width:40px;height:40px;color:var(--text-dark);transition:var(--transition);border:1px solid #e2e8f0;border-radius:50%;justify-content:center;align-items:center;font-size:16px;display:flex}.icon-btn:hover{background:#e2e8f0;transform:translateY(-1px)}.btn-install-pwa{background:var(--primary);color:#fff;cursor:pointer;transition:var(--transition);border:none;border-radius:9999px;align-items:center;gap:8px;padding:8px 16px;font-size:13px;font-weight:700;display:none;box-shadow:0 4px 12px #4318ff40}.btn-install-pwa:hover{background:var(--primary-hover);transform:translateY(-1px)}.view-section{animation:.25s ease-out forwards fadeIn;display:none}.view-section.active{display:block}@keyframes fadeIn{0%{opacity:0;transform:translateY(6px)}to{opacity:1;transform:translateY(0)}}.hero-banner{border-radius:var(--radius-xl);color:#fff;box-shadow:var(--shadow-md);background:linear-gradient(135deg,#1b2559 0%,#2b3674 50%,#4318ff 100%);justify-content:space-between;align-items:center;margin-bottom:28px;padding:32px 36px;display:flex;position:relative;overflow:hidden}.hero-banner:after{content:"";pointer-events:none;background:radial-gradient(circle,#ffffff1f 0%,#fff0 70%);border-radius:50%;width:240px;height:240px;position:absolute;bottom:-60px;right:-60px}.hero-content{z-index:1;max-width:580px}.hero-tag{-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);letter-spacing:.05em;text-transform:uppercase;color:#ffce20;background:#ffffff29;border-radius:9999px;margin-bottom:12px;padding:4px 12px;font-size:12px;font-weight:800;display:inline-block}.hero-title{letter-spacing:-.02em;margin-bottom:10px;font-size:28px;font-weight:800;line-height:1.25}.hero-description{color:#ffffffd1;margin-bottom:20px;font-size:15px;line-height:1.5}.hero-actions{flex-wrap:wrap;gap:12px;display:flex}.hero-illustration{z-index:1;justify-content:center;align-items:center;padding-left:16px;display:flex}.overall-accuracy-ring{-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);border-radius:var(--radius-lg);text-align:center;background:#ffffff1a;border:1px solid #fff3;min-width:150px;padding:20px}.accuracy-val{color:#ffce20;font-size:38px;font-weight:900;line-height:1}.accuracy-label{text-transform:uppercase;color:#ffffffd9;letter-spacing:.05em;margin-top:6px;font-size:12px;font-weight:700}.btn{border-radius:var(--radius-md);cursor:pointer;transition:var(--transition);border:none;justify-content:center;align-items:center;gap:8px;padding:12px 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#e2e8f0}.btn-outline:hover{background:#f1f5f9;border-color:#cbd5e1}.btn:disabled{opacity:.45;cursor:not-allowed;box-shadow:none!important;transform:none!important}.stats-grid{grid-template-columns:repeat(auto-fit,minmax(210px,1fr));gap:18px;margin-bottom:32px;display:grid}.stat-card{background:var(--bg-card);border-radius:var(--radius-lg);box-shadow:var(--shadow-sm);transition:var(--transition);border:1px solid #e2e8f0cc;align-items:center;gap:16px;padding:20px;display:flex}.stat-card:hover{box-shadow:var(--shadow-md);transform:translateY(-3px)}.stat-icon{border-radius:14px;flex-shrink:0;justify-content:center;align-items:center;width:52px;height:52px;font-size:24px;display:flex}.stat-icon.blue{background:var(--primary-light);color:var(--primary)}.stat-icon.green{background:var(--success-light);color:var(--success)}.stat-icon.amber{background:var(--warning-light);color:#d97706}.stat-icon.purple{color:#7e22ce;background:#f3e8ff}.stat-info .stat-value{color:var(--secondary);font-size:24px;font-weight:800;line-height:1.1}.stat-info .stat-label{color:var(--text-muted);margin-top:4px;font-size:13px;font-weight:600}.section-header{justify-content:space-between;align-items:center;margin-bottom:18px;display:flex}.section-title{color:var(--secondary);letter-spacing:-.02em;font-size:21px;font-weight:800}.section-subtitle{color:var(--text-muted);font-size:13px}.subject-grid{grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:20px;margin-bottom:36px;display:grid}.subject-card{background:var(--bg-card);border-radius:var(--radius-xl);box-shadow:var(--shadow-sm);transition:var(--transition);border:1px solid #e2e8f0cc;flex-direction:column;padding:24px;display:flex;position:relative;overflow:hidden}.subject-card:hover{box-shadow:var(--shadow-md);transform:translateY(-4px)}.subject-card:before{content:"";height:6px;position:absolute;top:0;left:0;right:0}.subject-card.maths:before{background:var(--subject-maths)}.subject-card.english:before{background:var(--subject-english)}.subject-card.vr:before{background:var(--subject-vr)}.subject-card.nvr:before{background:var(--subject-nvr)}.subject-header{justify-content:space-between;align-items:center;margin-bottom:14px;display:flex}.subject-badge{font-size:28px}.subject-tag{letter-spacing:.04em;text-transform:uppercase;border-radius:9999px;padding:4px 10px;font-size:11px;font-weight:800}.maths .subject-tag{color:var(--subject-maths);background:#eef2ff}.english .subject-tag{color:var(--subject-english);background:#ecfdf5}.vr .subject-tag{color:#d97706;background:#fffbeb}.nvr 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0%,#7033ff 100%);justify-content:space-between;align-items:center;margin-bottom:36px;padding:24px 32px;display:flex;position:relative;overflow:hidden}.mock-banner-info h3{margin-bottom:6px;font-size:20px;font-weight:800}.mock-banner-info p{color:#ffffffd9;max-width:600px;font-size:14px}.mock-banner-tags{gap:8px;margin-top:10px;display:flex}.mock-tag{background:#fff3;border-radius:9999px;padding:4px 10px;font-size:11px;font-weight:700}.history-card{background:var(--bg-card);border-radius:var(--radius-xl);box-shadow:var(--shadow-sm);border:1px solid #e2e8f0cc;padding:24px}.history-header{justify-content:space-between;align-items:center;margin-bottom:16px;display:flex}.empty-history-state{text-align:center;color:var(--text-muted);padding:40px 20px}.empty-history-icon{margin-bottom:8px;font-size:44px}.history-list{flex-direction:column;gap:10px;display:flex}.history-item{background:var(--bg-page);border-radius:var(--radius-md);transition:var(--transition);border:1px solid 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strong{color:var(--secondary)}.results-card{background:var(--bg-card);border-radius:var(--radius-xl);box-shadow:var(--shadow-lg);text-align:center;border:1px solid #e2e8f0cc;max-width:760px;margin:0 auto 32px;padding:40px}.results-trophy{margin-bottom:12px;font-size:64px;animation:1s ease-in-out infinite alternate bounceTrophy;display:inline-block}@keyframes bounceTrophy{0%{transform:translateY(0)}to{transform:translateY(-8px)}}.results-title{color:var(--secondary);margin-bottom:8px;font-size:30px;font-weight:900}.results-subtitle{color:var(--text-muted);margin-bottom:28px;font-size:15px}.score-display-box{background:var(--bg-page);border-radius:var(--radius-xl);border:1px solid #e2e8f0;justify-content:space-around;align-items:center;margin-bottom:28px;padding:24px;display:flex}.score-stat-col{text-align:center}.score-stat-big{color:var(--primary);font-size:42px;font-weight:900;line-height:1}.score-stat-text{text-transform:uppercase;color:var(--text-muted);letter-spacing:.04em;margin-top:6px;font-size:12px;font-weight:700}.results-breakdown-box{border-radius:var(--radius-lg);text-align:left;background:#f8fafc;margin-bottom:28px;padding:20px}.results-breakdown-title{color:var(--secondary);margin-bottom:12px;font-size:15px;font-weight:800}.results-breakdown-grid{grid-template-columns:repeat(auto-fit,minmax(140px,1fr));gap:12px;display:grid}.breakdown-item{border-radius:var(--radius-md);text-align:center;background:#fff;border:1px solid #e2e8f0;padding:12px}.breakdown-subj{color:var(--text-muted);margin-bottom:4px;font-size:12px;font-weight:700}.breakdown-score{color:var(--secondary);font-size:18px;font-weight:800}.results-actions{flex-wrap:wrap;justify-content:center;gap:12px;display:flex}.review-container{text-align:left;flex-direction:column;gap:18px;margin-top:24px;display:flex}.review-item-card{border-radius:var(--radius-lg);background:#f8fafc;border:1px solid #e2e8f0;padding:20px}.review-item-header{justify-content:space-between;align-items:center;margin-bottom:10px;display:flex}.review-q-num{color:var(--secondary);font-size:14px;font-weight:800}.review-badge{border-radius:9999px;padding:3px 8px;font-size:11px;font-weight:700}.review-badge.pass{background:var(--success-light);color:var(--success)}.review-badge.fail{background:var(--danger-light);color:var(--danger)}.modal-overlay{-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px);z-index:100;background:#0f172aa6;justify-content:center;align-items:center;padding:20px;display:none;position:fixed;inset:0}.modal-overlay.open{animation:.2s ease-out fadeIn;display:flex}.modal-card{background:var(--bg-card);border-radius:var(--radius-xl);width:100%;max-width:460px;box-shadow:var(--shadow-lg);border:1px solid #e2e8f0cc;padding:32px;position:relative}.modal-title{color:var(--secondary);margin-bottom:12px;font-size:20px;font-weight:800}.modal-body{color:var(--text-dark);margin-bottom:24px;font-size:14px;line-height:1.6}.ios-step{align-items:flex-start;gap:12px;margin-bottom:14px;display:flex}.ios-step-num{background:var(--primary-light);width:26px;height:26px;color:var(--primary);border-radius:50%;flex-shrink:0;justify-content:center;align-items:center;margin-top:2px;font-size:13px;font-weight:800;display:flex}.btn-close-modal{cursor:pointer;color:var(--text-muted);background:0 0;border:none;font-size:20px;position:absolute;top:18px;right:18px}.offline-banner{color:#fff;box-shadow:var(--shadow-lg);z-index:90;background:#1e293b;border:1px solid #ffffff26;border-radius:9999px;align-items:center;gap:8px;padding:10px 20px;font-size:13px;font-weight:600;display:none;position:fixed;bottom:20px;left:50%;transform:translate(-50%)}.offline-banner.active{display:inline-flex}@media 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