/* 基本的なスタイル */
body {
    font-family: Arial, sans-serif; /* フォントを指定 */
    margin: 0; /* マージンをリセット */
    padding: 0; /* パディングをリセット */
    background-color: #f4f4f4; /* 背景色 */
    color: #333; /* 文字色 */
}

/* ヘッダーのスタイル */
header {
    background-color: rgba(0, 0, 0, 0.8); /* 半透明の黒背景 */
    backdrop-filter: blur(20px); /* ぼかし効果 */
    color: #fff; /* 文字色 */
    padding: 0; /* パディングをリセット */
    text-align: center; /* 中央揃え */
    position: sticky; /* 画面上部に固定 */
    top: 0;
    z-index: 1000;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

header h1 {
    margin: 0;
    padding: 15px 0 5px 0;
    font-size: 1.8rem;
    font-weight: 600;
    letter-spacing: -0.5px;
}

/* ナビゲーションバーのスタイル */
.main-nav {
    margin: 0;
    padding: 8px 0 15px 0;
}

.main-nav ul {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 0;
    max-width: 980px;
    margin: 0 auto;
    padding: 0 20px;
}

.main-nav li {
    margin: 0;
}

.nav-link {
    display: inline-block;
    padding: 8px 16px;
    background-color: transparent;
    color: #f5f5f7; /* Apple風のライトグレー */
    text-decoration: none;
    border-radius: 0;
    transition: all 0.3s ease;
    font-size: 0.875rem;
    font-weight: 400;
    border: none;
    position: relative;
    letter-spacing: 0.011em;
}

.nav-link:hover {
    background-color: transparent;
    color: #fff;
    transform: none;
    box-shadow: none;
}

.nav-link.active {
    background-color: transparent;
    color: #fff;
    font-weight: 500;
}

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: -8px;
    left: 50%;
    transform: translateX(-50%);
    width: 4px;
    height: 4px;
    background-color: #007aff; /* Apple風のブルー */
    border-radius: 50%;
}

/* レスポンシブ対応 */
@media (max-width: 768px) {
    .main-nav ul {
        gap: 0;
        padding: 0 15px;
    }
    
    .nav-link {
        padding: 8px 12px;
        font-size: 0.8rem;
    }
    
    header h1 {
        font-size: 1.5rem;
    }
}

@media (max-width: 480px) {
    .main-nav ul {
        gap: 0;
        padding: 0 10px;
    }
    
    .nav-link {
        padding: 8px 8px;
        font-size: 0.75rem;
    }
    
    header h1 {
        font-size: 1.3rem;
        padding: 12px 0 5px 0;
    }
    
    .main-nav {
        padding: 5px 0 12px 0;
    }
}

/* メインコンテンツのスタイル */
main {
    padding: 40px 20px 20px 20px; /* 上部のパディングを増やして固定ヘッダーと重ならないように */
    max-width: 980px; /* Apple風の幅に調整 */
    margin: 0 auto; /* 中央揃え */
    background-color: #fff; /* 背景色 */
    min-height: calc(100vh - 200px); /* 最小高さを設定 */
}

section {
    margin-bottom: 20px; /* 下のマージン */
}

section h2 {
    color: #007bff; /* 文字色 */
}

ul {
    list-style-type: disc; /* リストのマーカー */
    margin-left: 20px; /* 左マージン */
}

/* プログラミングセクションのスタイル */
.programming-section {
    margin-top: 30px;
}

.programming-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
    margin-top: 20px;
}

.programming-card-link {
    text-decoration: none;
    color: inherit;
    display: block;
}

.programming-title-link {
    text-decoration: none;
    color: inherit;
}

.programming-title-link:hover h3 {
    text-decoration: underline;
}

.programming-card {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 25px;
    border-radius: 12px;
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
    color: white;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    position: relative;
    overflow: hidden;
    cursor: pointer;
}

.programming-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 35px rgba(0, 0, 0, 0.2);
}

.programming-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(255, 255, 255, 0.1);
    opacity: 0;
    transition: opacity 0.3s ease;
}

.programming-card:hover::before {
    opacity: 1;
}

.learn-more {
    margin-top: 15px;
    text-align: center;
    font-weight: bold;
    opacity: 0.8;
    transition: opacity 0.3s ease;
    color: white;
    text-decoration: none;
}

.programming-card-link:hover .learn-more {
    opacity: 1;
}

.programming-icon {
    font-size: 3rem;
    text-align: center;
    margin-bottom: 15px;
    height: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    width: 80px;
    margin: 0 auto 15px;
}

.programming-icon.python {
    background: linear-gradient(135deg, #3776ab, #ffd43b);
}

.programming-icon.c-lang {
    background: linear-gradient(135deg, #00599c, #004482);
}

.programming-icon.fortran {
    background: linear-gradient(135deg, #734f96, #b24592);
}

.programming-icon.stock {
    background: linear-gradient(135deg, #10b981, #059669);
}

.programming-icon.epub {
    background: linear-gradient(135deg, #8b5cf6, #7c3aed);
}

.programming-icon.git {
    background: linear-gradient(135deg, #f05032, #e44c2a);
}

.programming-card h3 {
    margin: 0 0 15px 0;
    font-size: 1.5rem;
    text-align: center;
}

.programming-card p {
    margin-bottom: 20px;
    line-height: 1.6;
    text-align: justify;
}

.programming-features {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    justify-content: center;
}

.feature-tag {
    background-color: rgba(255, 255, 255, 0.2);
    padding: 5px 12px;
    border-radius: 15px;
    font-size: 0.85rem;
    border: 1px solid rgba(255, 255, 255, 0.3);
    backdrop-filter: blur(10px);
}

/* 株のシミュレーション用スタイル */
.chart-container {
    background: white;
    border-radius: 10px;
    padding: 20px;
    margin: 20px 0;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    position: relative;
    height: 400px;
}

.chart-controls {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin: 20px 0;
}

.chart-btn {
    background: #e5e7eb;
    border: none;
    padding: 8px 16px;
    border-radius: 20px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: all 0.3s ease;
}

.chart-btn:hover {
    background: #d1d5db;
}

.chart-btn.active {
    background: #2563eb;
    color: white;
}

.stock-info {
    margin: 30px 0;
}

.stock-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin: 20px 0;
}

.stock-card {
    background: white;
    border-radius: 10px;
    padding: 20px;
    text-align: center;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
}

.stock-card:hover {
    transform: translateY(-2px);
}

.stock-card h4 {
    margin: 0 0 10px 0;
    color: #6b7280;
    font-size: 0.9rem;
    font-weight: 600;
}

.stock-price {
    font-size: 1.5rem;
    font-weight: bold;
    color: #1f2937;
    margin: 5px 0;
}

.stock-change {
    font-size: 0.9rem;
    font-weight: 600;
}

.stock-change.positive {
    color: #10b981;
}

.stock-change.negative {
    color: #ef4444;
}

.simulation-section {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-radius: 10px;
    padding: 30px;
    margin: 30px 0;
}

.coming-soon {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    padding: 20px;
    margin-top: 20px;
    backdrop-filter: blur(10px);
}

.coming-soon h4 {
    margin: 0 0 15px 0;
    color: #e0e7ff;
}

.coming-soon ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.coming-soon li {
    padding: 8px 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    position: relative;
    padding-left: 20px;
}

.coming-soon li:before {
    content: '▶';
    position: absolute;
    left: 0;
    color: #a5b4fc;
}

/* Git記事ページのスタイル */
.error-overview .code-block {
    background: #2d1b69;
    color: #fff;
    padding: 20px;
    border-radius: 8px;
    margin: 15px 0;
    border-left: 4px solid #f05032;
}

.error-overview .code-block pre {
    margin: 0;
    font-family: 'Courier New', monospace;
    font-size: 0.9rem;
    line-height: 1.4;
    white-space: pre-wrap;
    word-wrap: break-word;
}

.cause-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
    margin: 20px 0;
}

.cause-card {
    background: #fff;
    padding: 20px;
    border-radius: 10px;
    border-left: 4px solid #f05032;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.cause-card h3 {
    color: #f05032;
    margin-bottom: 10px;
}

.step-card {
    background: #fff;
    margin: 20px 0;
    padding: 25px;
    border-radius: 10px;
    border-left: 4px solid #10b981;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.step-card h3 {
    color: #10b981;
    margin-bottom: 15px;
}

.step-card .code-block {
    background: #f8f9fa;
    padding: 15px;
    border-radius: 6px;
    margin: 10px 0;
    border: 1px solid #e9ecef;
}

.step-card .code-block pre {
    margin: 0;
    font-family: 'Courier New', monospace;
    color: #333;
}

.prevention-grid, .best-practice-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
    margin: 20px 0;
}

.prevention-card, .practice-card {
    background: #fff;
    padding: 20px;
    border-radius: 10px;
    border-left: 4px solid #3b82f6;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.prevention-card h3, .practice-card h3 {
    color: #3b82f6;
    margin-bottom: 15px;
}

.trouble-card {
    background: #fff;
    margin: 20px 0;
    padding: 25px;
    border-radius: 10px;
    border-left: 4px solid #f59e0b;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.trouble-card h3 {
    color: #f59e0b;
    margin-bottom: 15px;
}

.trouble-solution h4 {
    color: #6b7280;
    margin: 20px 0 10px 0;
}

.case-timeline {
    margin: 20px 0;
}

.timeline-item {
    display: flex;
    align-items: flex-start;
    margin: 15px 0;
    padding: 15px;
    background: #fff;
    border-radius: 10px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.timeline-marker {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: 15px;
    flex-shrink: 0;
    font-size: 1.2rem;
}

.timeline-marker.error {
    background: #fef2f2;
    color: #dc2626;
}

.timeline-marker.action {
    background: #fef3c7;
    color: #f59e0b;
}

.timeline-marker.check {
    background: #d1fae5;
    color: #10b981;
}

.timeline-marker.success {
    background: #e0e7ff;
    color: #3b82f6;
}

.timeline-content h4 {
    margin: 0 0 5px 0;
    color: #374151;
}

.timeline-content p {
    margin: 0;
    color: #6b7280;
    font-size: 0.9rem;
}

.summary-section {
    background: #f0f9ff;
    padding: 30px;
    border-radius: 15px;
    border-left: 4px solid #0ea5e9;
    margin: 30px 0;
}

.resources-section a {
    color: #3b82f6;
    text-decoration: none;
    font-weight: 500;
}

.resources-section a:hover {
    text-decoration: underline;
}

/* レスポンシブデザイン */
@media (max-width: 768px) {
    .programming-grid {
        grid-template-columns: 1fr;
        gap: 15px;
    }
    
    .programming-card {
        padding: 20px;
    }
    
    main {
        margin: 10px;
        padding: 15px;
    }
    
    .cause-grid, .prevention-grid, .best-practice-grid {
        grid-template-columns: 1fr;
    }
    
    .timeline-item {
        flex-direction: column;
        text-align: center;
    }
    
    .timeline-marker {
        margin: 0 0 10px 0;
    }
}

/* フッターのスタイル */
footer {
    text-align: center; /* 中央揃え */
    padding: 1rem 0; /* 上下のパディング */
    background-color: #333; /* 背景色 */
    color: #fff; /* 文字色 */
    position: relative; /* 必要に応じて位置を調整 */
    bottom: 0;
    width: 100%;
}