:root {
    --primary: #007bff;
    --success: #28a745;
    --danger: #dc3545;
    --light: #f8f9fa;
}

body {
    font-family: 'Segoe UI', sans-serif;
    background-color: #e9ecef;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
}

.quiz-box {
    background: white;
    width: 90%;
    max-width: 500px;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
}

.quiz-header {
    display: flex;
    justify-content: space-between;
    margin-bottom: 1.5rem;
    font-weight: bold;
    color: #555;
}

.options-grid {
    display: grid;
    gap: 10px;
    margin: 20px 0;
}

button {
    padding: 12px;
    border: 2px solid var(--primary);
    background: white;
    color: var(--primary);
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
    transition: 0.3s;
}

button:hover:not([disabled]) {
    background: var(--primary);
    color: white;
}

button:disabled { cursor: not-allowed; }

#next-btn {
    width: 100%;
    background: var(--primary);
    color: white;
}

.hidden { display: none; }

/* Feedback Classes */
.correct { background-color: var(--success) !important; color: white !important; border-color: var(--success) !important; }
.wrong { background-color: var(--danger) !important; color: white !important; border-color: var(--danger) !important; }