/* 1. 基本設定とリセット */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: sans-serif;
    background: #f0f2f5;
    padding: 15px 8px;
    text-align: center;
    color: #333;
}

/* 2. レイアウトコンテナ */
.card {
    background: white;
    max-width: 720px;
    margin: 15px auto;
    padding: 20px 15px;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

/* 3. ボタン基本設定 */
.btn {
    padding: 13px 20px;
    font-size: 16px;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    transition: background 0.2s, transform 0.1s;
    font-weight: bold;
    -webkit-tap-highlight-color: transparent;
}

.btn:active {
    transform: scale(0.98);
}

/* 4. 〇✕ボタンの横並び（Flexbox） */
.answer-buttons {
    display: flex;
    justify-content: center;
    gap: 10px;
    flex-wrap: wrap;
    margin-top: 15px;
}

.answer-buttons .btn {
    flex: 1;
    min-width: 140px;
}

/* 5. ボタンの色バリエーション */
.btn-o { background: #ff4d4d; color: white; }
.btn-o:hover { background: #e63939; }

.btn-x { background: #3b82f6; color: white; }
.btn-x:hover { background: #2563eb; }

.btn-next {
    background: #10b981;
    color: white;
    width: 100%;
    margin-top: 15px;
}
.btn-next:hover { background: #059669; }

.btn-reset {
    background: #6b7280;
    color: white;
    width: 100%;
    max-width: 200px;
    margin: 10px auto 0;
    display: block;
}
.btn-reset:hover { background: #4b5563; }

.btn.m-top-30 {
    margin-top: 30px;
}

/* 6. テキスト・フィードバック領域 */
.feedback {
    padding: 15px;
    margin: 20px 0;
    border-radius: 5px;
    font-weight: bold;
    text-align: left;
    word-break: break-all;
}

.feedback.correct {
    background: #d1fae5;
    color: #065f46;
    border: 1px solid #10b981;
}

.feedback.incorrect {
    background: #fee2e2;
    color: #991b1b;
    border: 1px solid #ef4444;
}

.desc {
    font-weight: normal;
    margin-top: 10px;
    font-size: 15px;
    color: #4b5563;
    line-height: 1.6;
}

.question-text {
    font-size: 17px;
    font-weight: bold;
    line-height: 1.6;
    text-align: left;
    margin: 15px 0;
    word-break: break-all;
}

.result-score-text {
    font-size: 24px;
    font-weight: bold;
    color: #3b82f6;
    margin: 15px 0;
}

.result-notice {
    font-size: 14px;
    color: #6b7280;
    margin-bottom: 20px;
}

.hidden {
    display: none;
}