body {
    margin: 0;
    padding: 20px;
    font-family: 'Helvetica Neue', Arial, 'Hiragino Kaku Gothic ProN', 'Hiragino Sans', Meiryo, sans-serif;
    background: #fdf2f2;
    color: #333;
}

.container {
    max-width: 600px;
    margin: 0 auto;
    padding: 20px;
    background: white;
    border-radius: 15px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    text-align: center;
}

h1 {
    color: #ff0000;
    margin-bottom: 20px;
}

.btn {
    background: #ff0000;
    color: white;
    border: none;
    padding: 12px 25px;
    font-size: 18px;
    border-radius: 25px;
    cursor: pointer;
    transition: transform 0.2s, background 0.2s;
    margin-top: 15px;
    font-weight: bold;
}

.btn:hover {
    background: #cc0000;
    transform: scale(1.05);
}

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

.choice-btn {
    background: #f8f8f8;
    border: 2px solid #ddd;
    padding: 15px;
    border-radius: 10px;
    cursor: pointer;
    font-size: 16px;
    text-align: left;
    transition: all 0.2s;
}

.choice-btn:hover:not(:disabled) {
    background: #fff5f5;
    border-color: #ff0000;
}

.choice-btn:disabled {
    cursor: default;
}

.quiz-header {
    display: flex;
    justify-content: space-between;
    margin-bottom: 20px;
    font-weight: bold;
    color: #666;
}

.question-text {
    font-size: 20px;
    font-weight: bold;
    margin-bottom: 20px;
    line-height: 1.4;
}

.feedback {
    padding: 15px;
    border-radius: 10px;
    margin-top: 20px;
    animation: fadeIn 0.3s;
}

.correct-feedback {
    background: #e6ffed;
    border: 2px solid #28a745;
    color: #28a745;
}

.incorrect-feedback {
    background: #ffeef0;
    border: 2px solid #dc3545;
    color: #dc3545;
}

.score-circle {
    font-size: 48px;
    font-weight: bold;
    color: #ff0000;
    margin: 20px 0;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}