* { 
    box-sizing: border-box; 
}

body {
    font-family: 'Poppins', sans-serif;
    background: linear-gradient(135deg, #74ebd5 0%, #9face6 100%);
    margin: 0;
    color: #333;
}

h1, h2, h3, h4, h5, h6 { 
    font-weight: 700; 
}

.btn-option {
    width: 100%;
    text-align: left;
    padding: 16px 20px;
    margin: 8px 0;
    border: 2px solid #edf2f7;
    border-radius: 12px;
    background: #fff;
    font-size: 16px;
    font-weight: 600;
    color: #4a5568;
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn-option:hover:not(:disabled) {
    background: #edf2f7;
    border-color: #cbd5e0;
    transform: translateY(-2px);
}

.btn-option.correct {
    background: #27ae60 !important;
    border-color: #27ae60 !important;
    color: #fff !important;
}

.btn-option.wrong {
    background: #e74c3c !important;
    border-color: #e74c3c !important;
    color: #fff !important;
}

.btn-option:disabled { 
    cursor: not-allowed; 
    opacity: 0.9; 
}

.progress-bar {
    background: linear-gradient(90deg, #6a11cb, #2575fc);
    transition: width 0.4s ease;
}