* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    overflow-y: scroll;
}

:root {
    --primary: #087b8a;
    --secondary: #024450;
    --accent: #3ba3c5;
    --dark: #012a35;
    --light: #7eb3bf;
    --emphasis: #036982;
    --text-dark: #1a1a1a;
    --text-light: #6c757d;
    --bg-light: #f5f7f9;
    --white: #ffffff;
    --border: #dde2e6;
    --focus-outline: 2px solid var(--accent);
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.8;
    color: var(--text-dark);
    background-color: var(--bg-light);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

header {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: var(--white);
    padding: 1.5rem 0;
    text-align: center;
    box-shadow: 0 2px 8px rgba(8, 123, 138, 0.2);
}

header h1 {
    margin-bottom: 0.8rem;
    font-size: 1.8rem;
}

header h1 a {
    color: var(--white);
    text-decoration: none;
    transition: opacity 0.3s;
}

header h1 a:hover,
header h1 a:focus {
    opacity: 0.9;
    outline: none;
}

nav ul {
    list-style: none;
    display: flex;
    justify-content: center;
    gap: 2rem;
    font-size: 0.95rem;
}

nav a {
    color: var(--white);
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
    padding: 0.3rem 0;
    border-bottom: 2px solid transparent;
}

nav a:hover,
nav a:focus {
    border-bottom-color: var(--white);
    opacity: 0.9;
    outline: none;
}

main {
    flex: 1;
    width: 100%;
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem 1.5rem;
    background: var(--white);
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.05);
}

section {
    margin-bottom: 3rem;
}

section h2 {
    color: var(--dark);
    margin-bottom: 1rem;
    font-size: 1.75rem;
    border-bottom: 3px solid var(--accent);
    padding-bottom: 0.5rem;
    position: relative;
}

section h2::before {
    content: '';
    position: absolute;
    bottom: -3px;
    left: 0;
    width: 60px;
    height: 3px;
    background: var(--primary);
}

section p {
    margin-bottom: 1rem;
}

/* 投稿記事用のスタイル */
.post {
    max-width: 800px;
    margin: 0 auto;
}

.post-header {
    padding: 2rem 1.5rem 1.5rem;
    border-bottom: 3px solid var(--primary);
    margin: -2rem -1.5rem 2rem;
    background: var(--white);
}

.post-title {
    font-size: 2.25rem;
    margin-bottom: 0.75rem;
    font-weight: 700;
    color: var(--emphasis);
    line-height: 1.3;
    text-align: left;
}

.post-meta {
    font-size: 0.9rem;
    color: var(--text-light);
    display: flex;
    gap: 1rem;
    align-items: center;
}

.post-meta time {
    color: var(--secondary);
    font-weight: 500;
}

.post-author {
    color: var(--text-light);
}

.post-content {
    font-size: 1rem;
    line-height: 1.8;
}

.post-content h1 {
    font-size: 1.75rem;
    margin: 2rem 0 1rem;
    color: var(--dark);
}

.post-content h2 {
    font-size: 1.5rem;
    margin: 1.75rem 0 0.75rem;
    color: var(--dark);
    border-bottom: 2px solid var(--border);
    padding-bottom: 0.3rem;
    border-left: 4px solid var(--accent);
    padding-left: 0.75rem;
}

.post-content h3 {
    font-size: 1.25rem;
    margin: 1.5rem 0 0.5rem;
    color: var(--secondary);
}

.post-content ul, .post-content ol {
    margin-left: 2rem;
    margin-bottom: 1rem;
}

.post-content li {
    margin-bottom: 0.5rem;
}

.post-tags {
    display: flex;
    gap: 0.5rem;
    align-items: center;
}

.post .post-tags {
    margin-top: 2.5rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border);
}

.tag {
    display: inline-block;
    background: var(--light);
    padding: 0.2rem 0.6rem;
    border-radius: 4px;
    font-size: 0.75rem;
    margin-right: 0.5rem;
    color: var(--white);
    transition: all 0.3s ease;
}

.tag:hover {
    background: var(--primary);
    transform: translateY(-2px);
}

/* 投稿ナビゲーション */
.post-navigation {
    display: flex;
    justify-content: space-between;
    margin-top: 3rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border);
}

.post-navigation a {
    color: var(--accent);
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
}

.post-navigation a:hover {
    color: var(--primary);
    transform: translateX(5px);
}

.post-navigation .prev:hover {
    transform: translateX(-5px);
}

/* ブログ一覧 */
.post-list {
    list-style: none;
    margin-left: 0;
}

.post-list li {
    margin-bottom: 1rem;
    padding: 0.75rem 1rem;
    background: #f8fafa;
    border-radius: 6px;
    border-left: 3px solid var(--accent);
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
    transition: all 0.3s ease;
}

.post-list li:hover {
    transform: translateY(-2px);
    box-shadow: 0 3px 10px rgba(8, 123, 138, 0.12);
    background: #ffffff;
}

.post-date {
    color: var(--text-light);
    font-size: 0.85rem;
    font-weight: 500;
}

.post-list li a {
    color: var(--dark);
    text-decoration: none;
    font-size: 1rem;
    font-weight: 500;
    transition: color 0.3s ease;
}

.post-list li a:hover {
    color: var(--accent);
}

.view-all-posts {
    margin-top: 1.25rem;
    text-align: center;
}

.view-all-link {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
    color: var(--white);
    text-decoration: none;
    border-radius: 6px;
    font-weight: 500;
    font-size: 0.95rem;
    transition: all 0.3s ease;
    box-shadow: 0 2px 8px rgba(8, 123, 138, 0.2);
}

.view-all-link:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(8, 123, 138, 0.3);
}

.post-preview {
    margin-bottom: 1.5rem;
    padding: 1rem 1.25rem;
    background: #f8fafa;
    border-radius: 8px;
    border-left: 4px solid var(--accent);
    transition: all 0.3s ease;
}

.post-preview:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(8, 123, 138, 0.15);
    background: #ffffff;
}

.post-preview h2 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.post-preview h2 a {
    color: var(--dark);
    text-decoration: none;
    transition: color 0.3s ease;
}

.post-preview h2 a:hover {
    color: var(--accent);
}

.post-excerpt {
    display: none;
}

.read-more {
    color: var(--accent);
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
    display: inline-block;
}

.read-more:hover {
    color: var(--primary);
    transform: translateX(5px);
}

footer {
    background: linear-gradient(135deg, var(--secondary) 0%, var(--emphasis) 100%);
    color: var(--white);
    text-align: center;
    padding: 2rem 0;
    margin-top: 3rem;
    box-shadow: 0 -2px 8px rgba(8, 123, 138, 0.1);
}

footer a {
    color: var(--light);
    text-decoration: none;
    transition: all 0.3s ease;
}

footer a:hover {
    color: var(--white);
    text-decoration: underline;
}

footer p {
    margin-bottom: 0.5rem;
}

/* Aboutセクション */
.about-intro {
    font-size: 1.1rem;
    color: var(--text-dark);
    margin-bottom: 2rem;
    text-align: left;
}

.about-features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.feature-item {
    padding: 1rem 1.25rem;
    background: var(--bg-light);
    border-radius: 0.5rem;
    border-left: 4px solid var(--accent);
    transition: all 0.3s ease;
}

.feature-item:hover {
    transform: translateY(-4px);
    box-shadow: 0 6px 16px rgba(8, 123, 138, 0.15);
    border-left-color: var(--primary);
}

.feature-item h3 {
    font-size: 1.1rem;
    color: var(--dark);
    margin-bottom: 0.5rem;
}

.feature-item p {
    font-size: 0.95rem;
    color: var(--text-light);
    line-height: 1.5;
    margin-bottom: 0;
}

/* プロフィールセクション */
.profile-top {
    display: flex;
    align-items: flex-start;
    gap: 1.5rem;
}

.profile-avatar {
    flex: 0 0 auto;
    width: 140px;
    display: flex;
    flex-direction: column;
    align-items: flex-end;
}

.profile-avatar img {
    width: 140px;
    height: 140px;
    border-radius: 50%;
    object-fit: cover;
    background: var(--white);
    border: 3px solid var(--white);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.08);
    display: block;
}

.profile-illustration-credit {
    margin-top: 0.45rem;
    font-size: 0.75rem;
    line-height: 1.2;
    color: var(--text-light);
    text-align: right;
    white-space: nowrap;
}

.profile-illustration-credit a {
    color: inherit;
    text-decoration: none;
    border-bottom: 1px dotted var(--border);
}

.profile-illustration-credit a:hover,
.profile-illustration-credit a:focus {
    color: var(--primary);
    border-bottom-color: var(--primary);
    outline: none;
}

.profile-body {
    flex: 1;
    min-width: 0;
}

.profile-content h3 {
    color: var(--primary);
    font-size: 1.5rem;
    margin-bottom: 0.75rem;
}

.profile-intro {
    background: var(--bg-light);
    padding: 1rem;
    border-left: 4px solid var(--accent);
    margin: 1rem 0;
}

.profile-content h4 {
    color: var(--dark);
    font-size: 1.15rem;
    margin-top: 1.5rem;
    margin-bottom: 0.75rem;
    border-bottom: 2px solid var(--border);
    padding-bottom: 0.3rem;
}

.profile-content ul {
    list-style: none;
    padding-left: 0;
}

.profile-content ul li {
    padding-left: 1.5rem;
    position: relative;
    margin-bottom: 0.5rem;
}

.interest-list li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--accent);
    font-weight: bold;
}

.hobby-list li {
    padding-left: 2rem;
}

.hobby-list li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--accent);
    font-weight: bold;
}

.profile-links {
    margin-top: 1.5rem;
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.profile-links a {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.6rem 1.5rem;
    background: var(--accent);
    color: var(--white);
    text-decoration: none;
    border-radius: 0.5rem;
    font-weight: 500;
    transition: all 0.3s ease;
}

.profile-links a svg {
    flex-shrink: 0;
}

.profile-links a:hover {
    background: var(--primary);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(8, 123, 138, 0.3);
}

/* プロジェクトセクション */
.projects-content {
    padding: 1.5rem 0 2rem;
}

.projects-intro {
    text-align: center;
    margin-bottom: 1rem;
    color: var(--text-light);
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1rem;
    margin: 1.25rem 0 1.5rem;
}

.project-card {
    text-align: left;
    padding: 1rem 1.1rem;
    background: var(--bg-light);
    border-radius: 0.75rem;
    border: 1px solid var(--border);
    transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
}

.project-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 18px rgba(8, 123, 138, 0.12);
    border-color: rgba(8, 123, 138, 0.25);
}

.project-title {
    margin-bottom: 0.5rem;
    font-size: 1.05rem;
    line-height: 1.3;
}

.project-title a {
    color: var(--dark);
    text-decoration: none;
}

.project-title a:hover,
.project-title a:focus {
    color: var(--primary);
    outline: none;
}

.project-description {
    margin-bottom: 0.75rem;
    color: var(--text-light);
    font-size: 0.95rem;
    line-height: 1.55;
}

.project-link {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
    color: var(--primary);
    text-decoration: none;
    font-weight: 600;
}

.project-link:hover,
.project-link:focus {
    text-decoration: underline;
    outline: none;
}

.projects-extras {
    margin-top: 1.25rem;
}

.projects-contributions {
    background: var(--bg-light);
    border: 1px solid var(--border);
    border-radius: 0.75rem;
    padding: 0.9rem 1rem 1rem;
}

.projects-subtitle {
    font-size: 0.95rem;
    color: var(--dark);
    margin-bottom: 0.6rem;
}

.contributions-image {
    width: 100%;
    height: auto;
    display: block;
}

.projects-actions {
    margin-top: 1rem;
    text-align: center;
}

.projects-content p {
    margin-bottom: 0.75rem;
    color: var(--text-light);
}

.github-link {
    display: inline-block;
    margin-top: 1rem;
    padding: 0.75rem 2rem;
    background: var(--dark);
    color: var(--white);
    text-decoration: none;
    border-radius: 0.5rem;
    font-weight: 500;
    transition: all 0.3s ease;
}

.github-link:hover {
    background: var(--primary);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(8, 123, 138, 0.3);
}

/* コンタクトセクション */
.contact-list {
    list-style: none;
    padding-left: 0;
}

.contact-list li {
    padding: 0.75rem 0;
    border-bottom: 1px solid var(--border);
    font-size: 1rem;
}

.contact-list li:last-child {
    border-bottom: none;
}

.contact-list a {
    color: var(--accent);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

.contact-list a:hover {
    color: var(--primary);
    text-decoration: underline;
}

/* レスポンシブ対応 */
@media (max-width: 768px) {
    /* ヘッダー */
    header {
        padding: 1rem 0;
    }
    
    header h1 {
        font-size: 1.5rem;
    }
    
    nav ul {
        gap: 0.5rem;
    }
    
    nav a {
        font-size: 0.9rem;
        padding: 0.3rem 0.5rem;
    }
    
    /* メインコンテンツ */
    main {
        padding: 1rem 0.75rem;
        font-size: 0.9rem;
    }
    
    section {
        margin-bottom: 1.5rem;
    }
    
    section h2 {
        font-size: 1.3rem;
        margin-bottom: 0.75rem;
    }
    
    section p {
        font-size: 0.9rem;
        margin-bottom: 0.75rem;
    }
    
    /* Recent Posts */
    .post-list li {
        padding: 0.6rem 0.75rem;
        margin-bottom: 0.75rem;
    }
    
    .post-date {
        font-size: 0.75rem;
    }
    
    .post-list li a {
        font-size: 0.9rem;
    }
    
    .view-all-link {
        padding: 0.65rem 1.25rem;
        font-size: 0.85rem;
    }
    
    /* About セクション */
    .about-intro {
        font-size: 0.95rem;
        margin-bottom: 1.25rem;
    }
    
    .about-features {
        grid-template-columns: 1fr;
        gap: 0.75rem;
    }
    
    .feature-item h3 {
        font-size: 1rem;
        margin-bottom: 0.4rem;
    }
    
    .feature-item p {
        font-size: 0.85rem;
    }
    
    /* Profile */
    .profile-top {
        flex-direction: column;
        align-items: center;
        gap: 1rem;
    }

    .profile-avatar img {
        width: 100%;
        height: 100%;
    }

    .profile-avatar {
        width: 120px;
    }

    .profile-avatar img {
        width: 120px;
        height: 120px;
    }

    .profile-illustration-credit {
        font-size: 0.7rem;
    }

    .profile-body {
        width: 100%;
    }

    .profile-content h3 {
        font-size: 1.1rem;
    }
    
    .profile-intro {
        font-size: 0.85rem;
        line-height: 1.6;
    }
    
    .profile-content h4 {
        font-size: 0.95rem;
        margin-top: 1rem;
    }
    
    .interest-list li,
    .hobby-list li {
        font-size: 0.85rem;
        padding-left: 1.5rem;
    }
    
    .profile-links {
        flex-direction: column;
        gap: 0.6rem;
    }
    
    .profile-links a {
        width: 100%;
        justify-content: center;
        font-size: 0.9rem;
        padding: 0.6rem 1rem;
    }
    
    /* Projects & Contact */
    .projects-content p,
    .contact-list li {
        font-size: 0.85rem;
    }

    /* Projects */
    .projects-grid {
        grid-template-columns: 1fr;
        gap: 0.75rem;
        margin: 1rem 0 1.25rem;
    }

    .project-card {
        padding: 0.85rem 0.95rem;
    }

    .project-title {
        font-size: 1rem;
    }

    .project-description {
        font-size: 0.85rem;
    }

    .projects-extras {
        margin-top: 1rem;
    }

    .projects-contributions {
        padding: 0.8rem 0.9rem 0.95rem;
    }

    .github-link {
        width: 100%;
        text-align: center;
    }
    
    /* ブログ一覧 */
    .blog-list h1 {
        font-size: 1.3rem;
        margin-bottom: 0.8rem;
    }
    
    .post-preview {
        padding: 0.6rem 0.75rem;
        margin-bottom: 0.8rem;
    }
    
    .post-preview h2 {
        font-size: 1rem;
        margin-bottom: 0.3rem;
    }
    
    .post-meta {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.3rem;
        font-size: 0.75rem;
    }
    
    .post-tags {
        flex-wrap: wrap;
        gap: 0.25rem;
    }
    
    .tag {
        font-size: 0.6rem;
        padding: 0.12rem 0.4rem;
        margin-right: 0;
    }
    
    /* 記事ページ */
    .post-title {
        font-size: 1.4rem;
        line-height: 1.4;
    }
    
    .post-header {
        padding: 1.25rem 1rem 1rem;
        margin: -1rem -0.75rem 1.5rem;
    }
    
    .post-meta time {
        font-size: 0.75rem;
    }
    
    .post-author {
        font-size: 0.75rem;
    }
    
    .post-content {
        font-size: 0.9rem;
        line-height: 1.7;
    }
    
    .post-content h1,
    .post-content h2 {
        font-size: 1.15rem;
        margin: 1.25rem 0 0.6rem;
    }
    
    .post-content h3 {
        font-size: 1rem;
        margin: 1rem 0 0.5rem;
    }
    
    .post-content ul,
    .post-content ol {
        margin-left: 1.5rem;
        margin-bottom: 0.75rem;
    }
    
    .post-content li {
        font-size: 0.85rem;
        margin-bottom: 0.4rem;
    }
    
    .post .post-tags {
        margin-top: 1.75rem;
        padding-top: 1rem;
    }
}