/* 基本設定 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #2196F3;
    --primary-dark: #1976D2;
    --secondary-color: #4CAF50;
    --error-color: #f44336;
    --text-color: #333;
    --bg-color: #f5f5f5;
    --card-bg: #ffffff;
    --border-radius: 8px;
    --shadow: 0 2px 4px rgba(0,0,0,0.1);
    --shadow-hover: 0 4px 8px rgba(0,0,0,0.15);
}

html, body {
    height: 100%;
    overflow: hidden;
    position: fixed;
    width: 100%;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
        'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue',
        sans-serif;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    overscroll-behavior: none;
    touch-action: pan-y;
}

#app {
    max-width: 800px;
    margin: 0 auto;
    height: 100%;
    display: flex;
    flex-direction: column;
}

/* 画面管理 */
.screen {
    display: none;
    flex-direction: column;
    height: 100%;
    overflow: hidden;
}

.screen.active {
    display: flex;
}

/* ヘッダー */
header {
    background-color: var(--primary-color);
    color: white;
    padding: 1rem;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
}

header h1 {
    font-size: 1.5rem;
    text-align: center;
}

header h2 {
    font-size: 1.2rem;
    text-align: center;
}

.back-btn {
    background: transparent;
    border: none;
    color: white;
    font-size: 1rem;
    cursor: pointer;
    padding: 0.5rem;
    margin-bottom: 0.5rem;
}

.back-btn:hover {
    opacity: 0.8;
}

/* メイン */
main {
    flex: 1;
    padding: 1rem;
    overflow-y: auto;
    overflow-x: hidden;
    -webkit-overflow-scrolling: touch;
}

/* ボタン */
.menu-btn,
.mode-btn {
    background-color: var(--card-bg);
    border: 2px solid var(--primary-color);
    color: var(--primary-color);
    padding: 1rem 2rem;
    font-size: 1.1rem;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: all 0.3s;
    box-shadow: var(--shadow);
    width: 100%;
    max-width: 400px;
    margin: 0.5rem auto;
    display: block;
}

.menu-btn:hover,
.mode-btn:hover {
    background-color: var(--primary-color);
    color: white;
    box-shadow: var(--shadow-hover);
    transform: translateY(-2px);
}

.menu-btn:active,
.mode-btn:active {
    transform: translateY(0);
}

.mode-btn {
    text-align: left;
    padding: 1.5rem;
}

.mode-btn h3 {
    margin-bottom: 0.5rem;
    font-size: 1.2rem;
}

.mode-btn p {
    font-size: 0.9rem;
    opacity: 0.8;
}

/* セクションリスト */
.section-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.section-item {
    background-color: var(--card-bg);
    border: 2px solid var(--primary-color);
    color: var(--text-color);
    padding: 1rem;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: all 0.3s;
    box-shadow: var(--shadow);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.section-item:hover {
    background-color: var(--primary-color);
    color: white;
    box-shadow: var(--shadow-hover);
    transform: translateY(-2px);
}

.section-name {
    font-size: 1.1rem;
    font-weight: 500;
}

.section-status {
    font-size: 0.85rem;
    min-width: 120px;
    text-align: right;
    font-weight: 500;
}

/* 正答率別の色分け */
.section-item.score-perfect {
    background-color: #e8f5e9;
    border-color: #4CAF50;
}

.section-item.score-perfect:hover {
    background-color: #4CAF50;
    border-color: #4CAF50;
}

.section-item.score-high {
    background-color: #f1f8e9;
    border-color: #8BC34A;
}

.section-item.score-high:hover {
    background-color: #8BC34A;
    border-color: #8BC34A;
}

.section-item.score-medium {
    background-color: #fff9c4;
    border-color: #FFC107;
}

.section-item.score-medium:hover {
    background-color: #FFC107;
    border-color: #FFC107;
}

.section-item.score-low {
    background-color: #ffe0b2;
    border-color: #FF9800;
}

.section-item.score-low:hover {
    background-color: #FF9800;
    border-color: #FF9800;
}

.section-item.score-fail {
    background-color: #ffebee;
    border-color: #f44336;
}

.section-item.score-fail:hover {
    background-color: #f44336;
    border-color: #f44336;
}

/* プログレスバー */
.progress-bar {
    background-color: rgba(255, 255, 255, 0.3);
    height: 8px;
    border-radius: 4px;
    overflow: hidden;
    margin: 0.5rem 0;
}

.progress-fill {
    background-color: white;
    height: 100%;
    transition: width 0.3s;
    width: 0%;
}

.progress-text {
    text-align: center;
    font-size: 0.9rem;
    margin-top: 0.25rem;
}

/* 4択モード */
.quiz-container {
    max-width: 600px;
    margin: 0 auto;
}

.question-text {
    background-color: var(--card-bg);
    padding: 1.5rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    font-size: 1.2rem;
    margin-bottom: 1.5rem;
    line-height: 1.8;
}

.options-container {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.option-btn {
    background-color: var(--card-bg);
    border: 2px solid #ddd;
    color: var(--text-color);
    padding: 1rem;
    font-size: 1rem;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: all 0.3s;
    box-shadow: var(--shadow);
    text-align: left;
}

.option-btn:hover:not(:disabled) {
    border-color: var(--primary-color);
    box-shadow: var(--shadow-hover);
    transform: translateY(-2px);
}

.option-btn.correct {
    background-color: var(--secondary-color);
    border-color: var(--secondary-color);
    color: white;
}

.option-btn.incorrect {
    background-color: var(--error-color);
    border-color: var(--error-color);
    color: white;
}

.option-btn:disabled {
    cursor: not-allowed;
    opacity: 0.7;
}

.result-message {
    text-align: center;
    font-size: 1.5rem;
    font-weight: bold;
    margin: 1rem 0;
    min-height: 2rem;
}

.result-message.correct {
    color: var(--secondary-color);
}

.result-message.incorrect {
    color: var(--error-color);
}

.next-btn {
    background-color: var(--primary-color);
    border: none;
    color: white;
    padding: 1rem 2rem;
    font-size: 1.1rem;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: all 0.3s;
    box-shadow: var(--shadow);
    width: 100%;
    margin-top: 1rem;
}

.next-btn:hover {
    background-color: var(--primary-dark);
    box-shadow: var(--shadow-hover);
}

/* カードモード */
.card-container {
    max-width: 600px;
    margin: 0 auto;
}

.card-content {
    background-color: var(--card-bg);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    padding: 2rem;
    min-height: 300px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    transition: transform 0.3s;
    margin-bottom: 1.5rem;
}

.card-content:hover {
    transform: scale(1.02);
    box-shadow: var(--shadow-hover);
}

.card-question {
    font-size: 1.3rem;
    line-height: 1.8;
    text-align: center;
    margin-bottom: 1rem;
}

.card-answer {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
    text-align: center;
    margin-top: 1.5rem;
    padding-top: 1.5rem;
    border-top: 2px solid var(--primary-color);
}

.tap-hint {
    color: #999;
    font-size: 0.9rem;
    text-align: center;
    margin-top: 1rem;
}

.card-buttons {
    display: flex;
    gap: 1rem;
    justify-content: space-between;
}

.card-nav-btn {
    background-color: var(--primary-color);
    border: none;
    color: white;
    padding: 1rem 2rem;
    font-size: 1rem;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: all 0.3s;
    box-shadow: var(--shadow);
    flex: 1;
}

.card-nav-btn:hover:not(:disabled) {
    background-color: var(--primary-dark);
    box-shadow: var(--shadow-hover);
}

.card-nav-btn:disabled {
    background-color: #ccc;
    cursor: not-allowed;
}

/* 統計情報 */
.stats-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1rem;
    max-width: 600px;
    margin: 0 auto;
}

.stat-card {
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    text-align: center;
}

.stat-card h3 {
    font-size: 1.1rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.stat-value {
    font-size: 2.5rem;
    font-weight: bold;
    color: var(--text-color);
}

/* 結果画面 */
.result-container {
    max-width: 600px;
    margin: 0 auto;
    text-align: center;
}

.result-container h3 {
    font-size: 1.8rem;
    margin-bottom: 2rem;
    color: var(--primary-color);
}

.result-stats {
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    margin-bottom: 2rem;
}

.result-stats p {
    font-size: 1.3rem;
    margin: 1rem 0;
}

.result-stats span {
    font-weight: bold;
    color: var(--primary-color);
}

.result-buttons {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

/* レスポンシブ */
@media (max-width: 600px) {
    header h1 {
        font-size: 1.2rem;
    }

    .question-text {
        font-size: 1rem;
        padding: 1rem;
    }

    .card-question {
        font-size: 1.1rem;
    }

    .card-answer {
        font-size: 1.3rem;
    }

    .stat-value {
        font-size: 2rem;
    }
}