body {
    font-family: 'Hiragino Sans', 'Hiragino Kaku Gothic ProN', Meiryo, sans-serif;
    margin: 20px;
    line-height: 1.6;
    color: #333;
    background-color: #f9f9f9;
}
.container {
    max-width: 900px;
    margin: 0 auto;
    background-color: #fff;
    padding: 20px;
    border-radius: 5px;
    box-shadow: 0 1px 5px rgba(0,0,0,0.05);
}
h1 {
    color: #333;
    border-bottom: 1px solid #eee;
    padding-bottom: 10px;
    font-size: 22px;
}
.back-link {
    margin-bottom: 20px;
}
.back-link a {
    color: #0066cc;
    text-decoration: none;
}
.back-link a:hover {
    text-decoration: underline;
}
.sitemap-section {
    margin-bottom: 25px;
}
.sitemap-section h2 {
    color: #444;
    font-size: 18px;
    margin-bottom: 10px;
    padding-bottom: 5px;
    border-bottom: 1px solid #eee;
}
.sitemap-list {
    list-style-type: none;
    padding-left: 0;
}
.sitemap-list ul {
    list-style-type: none;
    padding-left: 20px;
}
.sitemap-list li {
    margin: 5px 0;
}
.sitemap-list a {
    text-decoration: none;
    color: #0066cc;
}
.sitemap-list a:hover {
    text-decoration: underline;
}
.sitemap-list .folder::before {
    content: "📁 ";
}
.sitemap-list .file::before {
    content: "📄 ";
}
.sitemap-list .external::before {
    content: "🔗 ";
}
.sitemap-list .category-button {
    display: inline-block;
    background-color: #f0f5ff;
    border: 1px solid #d0e0ff;
    border-radius: 3px;
    padding: 2px 8px;
    margin: 2px 5px 2px 0;
    color: #0055cc;
}
.sitemap-list .category-button:hover {
    background-color: #e0ecff;
}
footer {
    margin-top: 20px;
    text-align: center;
    font-size: 13px;
    color: #777;
    padding-top: 15px;
    border-top: 1px solid #eee;
}

/* Java コンテンツ表のスタイル */
.java-content-table {
    width: 100%;
    border-collapse: collapse;
    margin: 15px 0;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}
.java-content-table th {
    background-color: #f5f5f5;
    padding: 10px;
    text-align: left;
    border-bottom: 2px solid #ddd;
}
.java-content-table td {
    padding: 12px 10px;
    border-bottom: 1px solid #eee;
}
.java-content-table tr:hover {
    background-color: #f9f9f9;
}
.java-content-cell {
    position: relative;
    z-index: 1;
}
.java-content-cell a {
    font-weight: bold;
}
.java-content-cell p {
    margin: 5px 0 0 0;
    font-size: 0.9em;
    color: #555;
}

/* モバイル用スタイル */
@media screen and (max-width: 768px) {
    /* モバイル用フッタースタイル */
    footer p {
        display: flex;
        flex-direction: column;
        align-items: center;
        line-height: 2.5;
    }
    
    footer a {
        padding: 8px 16px;
        display: block;
        font-size: 16px;
    }
    
    .separator {
        display: none;
    }
}

/* 背景SVGパターン */
.java-syntax-bg {
    position: relative;
    overflow: hidden;
}
.java-syntax-bg::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='100' height='100' viewBox='0 0 100 100'%3E%3Cpath fill='none' stroke='%23f0f0f0' stroke-width='2' d='M10,10 L90,10 L90,90 L10,90 L10,10 M30,10 L30,90 M50,10 L50,90 M70,10 L70,90 M10,30 L90,30 M10,50 L90,50 M10,70 L90,70'/%3E%3C/svg%3E");
    background-size: 50px 50px;
    opacity: 0.3;
    z-index: 0;
}

.java-oop-bg {
    position: relative;
    overflow: hidden;
}
.java-oop-bg::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='100' height='100' viewBox='0 0 100 100'%3E%3Ccircle cx='25' cy='25' r='15' fill='none' stroke='%23e0e0ff' stroke-width='2'/%3E%3Ccircle cx='75' cy='25' r='15' fill='none' stroke='%23e0e0ff' stroke-width='2'/%3E%3Ccircle cx='25' cy='75' r='15' fill='none' stroke='%23e0e0ff' stroke-width='2'/%3E%3Ccircle cx='75' cy='75' r='15' fill='none' stroke='%23e0e0ff' stroke-width='2'/%3E%3Cpath fill='none' stroke='%23e0e0ff' stroke-width='2' d='M40,25 L60,25 M25,40 L25,60 M75,40 L75,60 M40,75 L60,75'/%3E%3C/svg%3E");
    background-size: 50px 50px;
    opacity: 0.3;
    z-index: 0;
}

.java-collections-bg {
    position: relative;
    overflow: hidden;
}
.java-collections-bg::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='100' height='100' viewBox='0 0 100 100'%3E%3Crect x='10' y='10' width='20' height='20' fill='none' stroke='%23e0f0e0' stroke-width='2'/%3E%3Crect x='40' y='10' width='20' height='20' fill='none' stroke='%23e0f0e0' stroke-width='2'/%3E%3Crect x='70' y='10' width='20' height='20' fill='none' stroke='%23e0f0e0' stroke-width='2'/%3E%3Crect x='10' y='40' width='20' height='20' fill='none' stroke='%23e0f0e0' stroke-width='2'/%3E%3Crect x='40' y='40' width='20' height='20' fill='none' stroke='%23e0f0e0' stroke-width='2'/%3E%3Crect x='70' y='40' width='20' height='20' fill='none' stroke='%23e0f0e0' stroke-width='2'/%3E%3Cpath fill='none' stroke='%23e0f0e0' stroke-width='2' d='M30,20 L40,20 M60,20 L70,20 M20,30 L20,40 M50,30 L50,40 M80,30 L80,40'/%3E%3C/svg%3E");
    background-size: 50px 50px;
    opacity: 0.3;
    z-index: 0;
}

.java-patterns-bg {
    position: relative;
    overflow: hidden;
}
.java-patterns-bg::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='100' height='100' viewBox='0 0 100 100'%3E%3Cpolygon points='25,10 40,30 10,30' fill='none' stroke='%23f0e0e0' stroke-width='2'/%3E%3Cpolygon points='75,10 90,30 60,30' fill='none' stroke='%23f0e0e0' stroke-width='2'/%3E%3Cpolygon points='25,60 40,80 10,80' fill='none' stroke='%23f0e0e0' stroke-width='2'/%3E%3Cpolygon points='75,60 90,80 60,80' fill='none' stroke='%23f0e0e0' stroke-width='2'/%3E%3Cpath fill='none' stroke='%23f0e0e0' stroke-width='2' d='M25,30 L25,60 M75,30 L75,60 M40,30 L60,30 M40,80 L60,80'/%3E%3C/svg%3E");
    background-size: 50px 50px;
    opacity: 0.3;
    z-index: 0;
}