*{box-sizing:border-box;margin:0;padding:0}:root{--primary: #2563eb;--primary-dark: #1d4ed8;--secondary: #7c3aed;--success: #16a34a;--warning: #d97706;--danger: #dc2626;--bg: #f8fafc;--card-bg: #ffffff;--text: #1e293b;--text-light: #64748b;--border: #e2e8f0;--radius: 12px;--shadow: 0 1px 3px rgba(0,0,0,.1), 0 1px 2px rgba(0,0,0,.06);--shadow-md: 0 4px 6px rgba(0,0,0,.07), 0 2px 4px rgba(0,0,0,.06);--shadow-lg: 0 10px 15px rgba(0,0,0,.1), 0 4px 6px rgba(0,0,0,.05)}body{font-family:Inter,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;background:var(--bg);color:var(--text);min-height:100vh;line-height:1.6}a{text-decoration:none;color:inherit}button{cursor:pointer;border:none;font-family:inherit}.container{max-width:1100px;margin:0 auto;padding:0 1.5rem}.page-content{padding:2rem 0 4rem}.page-header{margin-bottom:2rem}.page-header h1{font-size:2rem;font-weight:700;color:var(--text)}.page-header p{margin-top:.5rem;color:var(--text-light);font-size:1.05rem}.card{background:var(--card-bg);border-radius:var(--radius);box-shadow:var(--shadow);border:1px solid var(--border);padding:1.5rem}.badge{display:inline-block;padding:.2rem .6rem;border-radius:9999px;font-size:.75rem;font-weight:600}.badge.badge-blue{background:#dbeafe;color:#1d4ed8}.badge.badge-purple{background:#ede9fe;color:#6d28d9}.badge.badge-green{background:#dcfce7;color:#15803d}.badge.badge-orange{background:#ffedd5;color:#c2410c}.btn{display:inline-flex;align-items:center;gap:.4rem;padding:.6rem 1.2rem;border-radius:8px;font-size:.9rem;font-weight:500;transition:all .15s}.btn.btn-primary{background:var(--primary);color:#fff}.btn.btn-primary:hover{background:var(--primary-dark)}.btn.btn-outline{background:transparent;border:1.5px solid var(--border);color:var(--text)}.btn.btn-outline:hover{background:var(--bg);border-color:var(--primary);color:var(--primary)}.btn.btn-success{background:var(--success);color:#fff}.btn.btn-success:hover{background:#15803d}.btn.btn-danger{background:var(--danger);color:#fff}.btn.btn-danger:hover{background:#b91c1c}.btn:disabled{opacity:.5;cursor:not-allowed}.grid-2{display:grid;grid-template-columns:repeat(2,1fr);gap:1.5rem}@media(max-width:700px){.grid-2{grid-template-columns:1fr}}.grid-3{display:grid;grid-template-columns:repeat(3,1fr);gap:1.5rem}@media(max-width:900px){.grid-3{grid-template-columns:repeat(2,1fr)}}@media(max-width:600px){.grid-3{grid-template-columns:1fr}}.section-title{font-size:1.3rem;font-weight:600;margin-bottom:1rem;display:flex;align-items:center;gap:.5rem}.section-title:before{content:"";display:inline-block;width:4px;height:1.2em;background:var(--primary);border-radius:2px}.progress-bar{height:8px;background:var(--border);border-radius:9999px;overflow:hidden}.progress-bar .progress-fill{height:100%;background:var(--primary);border-radius:9999px;transition:width .4s ease}.correct{color:var(--success)}.incorrect{color:var(--danger)}