body {
    background: #f0f2f5;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", sans-serif;
    -webkit-font-smoothing: antialiased;
}
.navbar-brand {
    font-weight: 700;
    font-size: 1.2rem;
}
.card {
    border: none;
    border-radius: 12px;
    box-shadow: 0 2px 12px rgba(0,0,0,0.08);
}
.card:hover {
    box-shadow: 0 4px 20px rgba(0,0,0,0.12);
}
.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border: none;
    border-radius: 8px;
}
.btn-primary:hover {
    background: linear-gradient(135deg, #5a6fd6 0%, #6a4190 100%);
}
.quiz-option {
    display: block;
    padding: 14px 20px;
    margin: 8px 0;
    border: 2px solid #e0e0e0;
    border-radius: 10px;
    cursor: pointer;
    transition: all 0.2s;
    background: #fff;
    font-size: 1rem;
    -webkit-tap-highlight-color: transparent;
}
.quiz-option:hover {
    border-color: #667eea;
    background: #f8f0ff;
}
.quiz-option.selected {
    border-color: #667eea;
    background: #f0ebff;
}
.quiz-option input {
    margin-right: 10px;
}
.progress-bar-custom {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}
.stat-card {
    text-align: center;
    padding: 16px;
}
.stat-card .stat-number {
    font-size: 2rem;
    font-weight: 700;
    color: #667eea;
    line-height: 1.2;
}
.stat-card .stat-label {
    color: #888;
    font-size: 0.85rem;
}
.correct { color: #28a745; }
.wrong { color: #dc3545; }
.answer-box {
    padding: 12px 16px;
    border-radius: 8px;
    margin: 6px 0;
}
.answer-correct {
    background: #d4edda;
    border-left: 4px solid #28a745;
}
.answer-wrong {
    background: #f8d7da;
    border-left: 4px solid #dc3545;
}
.quiz-type-badge {
    font-size: 0.75rem;
    padding: 3px 8px;
    border-radius: 12px;
}
.auth-container {
    max-width: 420px;
    margin: 80px auto;
}

/* Quick action cards */
.quick-action-card {
    display: flex;
    align-items: center;
    padding: 16px;
    background: #fff;
    border-radius: 12px;
    box-shadow: 0 2px 12px rgba(0,0,0,0.08);
    text-decoration: none;
    color: inherit;
    transition: all 0.2s;
    -webkit-tap-highlight-color: transparent;
}
.quick-action-card:hover {
    box-shadow: 0 4px 20px rgba(0,0,0,0.14);
    transform: translateY(-2px);
    color: inherit;
}
.quick-action-card:active {
    transform: translateY(0);
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}
.qa-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}
.qa-text {
    margin-left: 14px;
}
.qa-title {
    font-size: 0.95rem;
    font-weight: 600;
    color: #333;
}
.qa-desc {
    font-size: 0.78rem;
    color: #999;
    margin-top: 2px;
}

/* Mobile responsive */
@media (max-width: 576px) {
    .container {
        padding-left: 12px;
        padding-right: 12px;
    }
    .card {
        border-radius: 10px;
    }
    .stat-card {
        padding: 12px;
    }
    .stat-card .stat-number {
        font-size: 1.6rem;
    }
    .stat-card .stat-label {
        font-size: 0.75rem;
    }
    .quiz-option {
        padding: 12px 16px;
        margin: 6px 0;
        font-size: 0.95rem;
    }
    .btn {
        font-size: 0.95rem;
    }
    .btn-lg {
        font-size: 1.1rem;
        padding: 12px;
    }
    .navbar-brand {
        font-size: 1rem;
    }
    h4 { font-size: 1.3rem; }
    h5 { font-size: 1.1rem; }
    h6 { font-size: 1rem; }
    .table {
        font-size: 0.85rem;
    }
    .table .btn-sm {
        font-size: 0.75rem;
        padding: 2px 6px;
    }
    .qa-icon {
        width: 40px;
        height: 40px;
        border-radius: 10px;
    }
    .qa-icon svg {
        width: 22px;
        height: 22px;
    }
    .qa-text {
        margin-left: 10px;
    }
    .qa-title {
        font-size: 0.88rem;
    }
    .qa-desc {
        font-size: 0.72rem;
    }
}