*{margin:0;padding:0;box-sizing:border-box}:root{--aws-orange: #FF9900;--aws-dark: #232F3E;--aws-light: #31C5F0;--bg-primary: #ffffff;--bg-secondary: #f5f7fa;--text-primary: #1a1a1a;--text-secondary: #666666;--border-color: #e0e0e0;--success: #4caf50;--error: #f44336;--warning: #ff9800}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Fira Sans,Droid Sans,Helvetica Neue,sans-serif;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;background-color:var(--bg-secondary);color:var(--text-primary);line-height:1.6}.app{min-height:100vh;padding:20px}.container{max-width:900px;margin:0 auto}.auth-panel{margin:0 0 28px;padding:18px 20px;border:1px solid var(--border-color);border-radius:8px;background:var(--bg-primary)}.auth-form{display:grid;gap:10px;max-width:620px;margin:0 auto}.auth-heading,.auth-signed-in{display:flex;align-items:center;justify-content:space-between;gap:16px}.auth-heading h2{font-size:1.05rem}.auth-form input{width:100%;padding:10px 12px;border:1px solid var(--border-color);border-radius:6px;font:inherit}.auth-switch{border:0;background:transparent;color:#1565c0;cursor:pointer;font:inherit}.auth-message{color:var(--text-secondary);font-size:.9rem}.auth-actions{display:flex;flex-wrap:wrap;gap:8px;justify-content:flex-end}.progress-page{padding:28px;border:1px solid var(--border-color);border-radius:8px;background:var(--bg-primary)}.progress-page-header{display:flex;align-items:flex-start;justify-content:space-between;gap:18px;margin-bottom:28px}.progress-page-header h1{margin-top:4px;font-size:2rem}.progress-page-header p,.progress-stat span,.progress-attempt span{color:var(--text-secondary)}.progress-stats-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:12px}.progress-stat{display:grid;gap:4px;padding:16px;border:1px solid var(--border-color);border-radius:6px}.progress-stat strong{color:var(--aws-orange);font-size:1.6rem}.progress-stat span,.progress-attempt span{font-size:.84rem}.progress-history{display:grid;gap:8px}.progress-attempt{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:14px 16px;border:1px solid var(--border-color);border-radius:6px}.progress-attempt div{display:grid;gap:3px}@media (max-width: 600px){.auth-heading,.auth-signed-in{align-items:flex-start;flex-direction:column}}.version-badge{display:flex;align-items:center;gap:10px;width:fit-content;max-width:100%;margin:0 0 18px auto;padding:8px 12px;border:1px solid rgba(35,47,62,.18);border-radius:8px;background:#fff;box-shadow:0 2px 8px #232f3e14;color:var(--aws-dark);font-size:.82rem;line-height:1.2}.version-badge-main{padding:4px 8px;border-radius:6px;background:var(--aws-dark);color:#fff;font-weight:800;letter-spacing:0}.version-badge-detail{font-weight:700}.version-badge-stack{color:var(--text-secondary)}.header{text-align:center;margin-bottom:40px;padding:30px;background:linear-gradient(135deg,var(--aws-orange) 0%,var(--aws-dark) 100%);color:#fff;border-radius:12px;box-shadow:0 4px 6px #0000001a}.header h1{font-size:2.5rem;margin-bottom:10px}.subtitle{font-size:1.1rem;opacity:.9;margin-bottom:20px}.progress{display:flex;justify-content:space-between;max-width:400px;margin:0 auto;padding:10px 20px;background:#fff3;border-radius:20px;font-size:.95rem}.question-card{background:var(--bg-primary);padding:40px;border-radius:12px;box-shadow:0 2px 8px #0000001a;margin-bottom:30px}.question-meta{display:flex;gap:10px;margin-bottom:20px}.badge{padding:6px 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a{color:var(--aws-light);text-decoration:none;font-weight:500}.references a:hover{text-decoration:underline}.actions{display:flex;justify-content:center;margin-top:30px}.btn{padding:14px 32px;font-size:1rem;font-weight:600;border:none;border-radius:8px;cursor:pointer;transition:all .2s ease;font-family:inherit}.btn-primary{background:var(--aws-orange);color:#fff}.btn-primary:hover:not(:disabled){background:#e68a00;transform:translateY(-2px);box-shadow:0 4px 12px #ff99004d}.btn-primary:disabled{background:#ccc;cursor:not-allowed;opacity:.6}.quiz-complete{text-align:center;padding:60px 40px;background:var(--bg-primary);border-radius:12px;box-shadow:0 2px 8px #0000001a}.quiz-complete h1{font-size:2.5rem;margin-bottom:30px;color:var(--aws-orange)}.score-card{background:linear-gradient(135deg,var(--aws-orange) 0%,var(--aws-dark) 100%);color:#fff;padding:40px;border-radius:12px;margin:30px 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h2{font-size:1.5rem;margin-bottom:20px;color:var(--text-primary);display:flex;align-items:center;gap:10px}.option-cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:20px;margin-bottom:20px}.option-card{padding:25px;border:2px solid var(--border-color);border-radius:12px;cursor:pointer;transition:all .3s ease;background:var(--bg-primary)}.option-card:hover{border-color:var(--aws-orange);transform:translateY(-2px);box-shadow:0 4px 12px #f903}.option-card.selected{border-color:var(--aws-orange);background:#fff8f0;box-shadow:0 4px 12px #ff99004d}.option-card-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:15px}.option-card h3{font-size:1.3rem;color:var(--text-primary);margin:0}.question-count{background:var(--aws-orange);color:#fff;padding:4px 12px;border-radius:20px;font-size:.85rem;font-weight:600}.option-card p{color:var(--text-secondary);margin-bottom:15px;line-height:1.5}.option-features{list-style:none;padding:0;margin:0}.option-features li{padding:6px 0;color:var(--text-secondary);font-size:.95rem}.domain-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(250px,1fr));gap:15px}.domain-card{padding:20px;border:2px solid var(--border-color);border-radius:10px;cursor:pointer;transition:all .2s ease;background:var(--bg-primary)}.domain-card:hover{border-color:var(--aws-light);transform:translateY(-2px);box-shadow:0 3px 10px #31c5f033}.domain-card.selected{border-color:var(--aws-light);background:#f0faff;box-shadow:0 3px 10px #31c5f04d}.domain-card-content h3{font-size:1.1rem;color:var(--text-primary);margin-bottom:10px}.domain-meta{display:flex;justify-content:space-between;align-items:center;font-size:.9rem}.domain-weight{background:var(--bg-secondary);padding:3px 10px;border-radius:12px;font-weight:600;color:var(--text-secondary)}.domain-questions{color:var(--aws-light);font-weight:600}.count-options{display:flex;gap:15px;justify-content:center;flex-wrap:wrap}.count-btn{padding:15px 30px;font-size:1.1rem;font-weight:600;border:2px solid var(--border-color);border-radius:10px;background:var(--bg-primary);color:var(--text-primary);cursor:pointer;transition:all .2s ease;font-family:inherit;min-width:140px}.count-btn:hover{border-color:var(--aws-orange);transform:translateY(-2px);box-shadow:0 3px 10px #f903}.count-btn.selected{border-color:var(--aws-orange);background:var(--aws-orange);color:#fff;box-shadow:0 3px 10px #f906}.start-section{text-align:center;padding:30px;background:var(--bg-secondary);border-radius:10px;margin-top:40px}.quiz-summary{margin-bottom:25px;font-size:1.1rem;color:var(--text-primary)}.quiz-summary p{margin:8px 0}.quiz-count{font-size:1.3rem;color:var(--aws-orange)}.btn-large{padding:16px 48px;font-size:1.2rem;min-width:200px}.btn-primary:disabled{background:#ccc;cursor:not-allowed;opacity:.6;transform:none}@media (max-width: 768px){.progress-page-header{display:grid}.progress-stats-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.header h1{font-size:2rem}.version-badge{align-items:flex-start;flex-direction:column;margin-right:auto}.question-card{padding:25px}.question-text{font-size:1.1rem}.option{padding:15px}.score-number,.welcome-header h1{font-size:2.5rem}.welcome-subtitle{font-size:1.1rem}.quiz-options{padding:25px}.option-cards,.domain-grid{grid-template-columns:1fr}.btn-large{padding:14px 32px;font-size:1.1rem;width:100%}.count-options{flex-direction:column}.count-btn{width:100%}}