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

:root {
    --primary-color: #6366f1;
    --secondary-color: #8b5cf6;
    --dark-bg: #0f172a;
    --light-bg: #f8fafc;
    --card-bg: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;
    --gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
}

body {
    font-family: 'Noto Sans JP', 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
    background-attachment: fixed;
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
}

body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: 
        radial-gradient(circle at 20% 50%, rgba(255, 255, 255, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(255, 255, 255, 0.1) 0%, transparent 50%);
    pointer-events: none;
    z-index: 0;
}

header {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-lg);
    padding: 2rem 1rem;
    text-align: center;
    position: relative;
    z-index: 1;
    margin-bottom: 3rem;
}

header h1 {
    font-family: 'M PLUS Rounded 1c', 'Noto Sans JP', sans-serif;
    font-size: 2.5rem;
    font-weight: 500;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 0.5rem;
    letter-spacing: 0.03em;
    line-height: 1.4;
}


main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem 3rem;
    position: relative;
    z-index: 1;
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
    flex: 1;
}

section {
    background: var(--card-bg);
    border-radius: 1rem;
    padding: 2rem;
    box-shadow: var(--shadow-xl);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: var(--gradient);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.3s ease;
}

section:hover {
    transform: translateY(-5px);
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
}

section:hover::before {
    transform: scaleX(1);
}

section h2 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

section h2 a {
    color: var(--text-primary);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    transition: all 0.2s ease;
}

section h2 a:hover {
    color: var(--primary-color);
}

section h2 a .link-icon {
    font-size: 0.85rem;
    opacity: 0.7;
    margin-left: 0.25rem;
    transition: all 0.2s ease;
}

section h2 a:hover .link-icon {
    opacity: 1;
    transform: translate(2px, -2px);
}

section h2::before {
    content: '';
    width: 4px;
    height: 24px;
    background: var(--gradient);
    border-radius: 2px;
}

section p {
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 1rem;
}

section ul {
    list-style: none;
}


section a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    transition: all 0.2s ease;
    padding: 0.5rem 0;
    position: relative;
}

section a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient);
    transition: width 0.3s ease;
}

section a:hover {
    color: var(--secondary-color);
    transform: translateX(5px);
}

section a:hover::after {
    width: 100%;
}

section a i {
    font-size: 0.9rem;
    transition: transform 0.2s ease;
}

section a:hover i {
    transform: translateX(3px);
}

footer {
    background: rgba(15, 23, 42, 0.8);
    backdrop-filter: blur(10px);
    color: rgba(255, 255, 255, 0.9);
    text-align: center;
    padding: 2rem 1rem;
    margin-top: auto;
    position: relative;
    z-index: 1;
}

footer p {
    font-size: 0.9rem;
}

.footer-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: 0.75rem;
}

.footer-links {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    justify-content: center;
}

.footer-links a {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
    padding: 0.3rem 0.75rem;
    border-radius: 999px;
    border: 1px solid rgba(148, 163, 184, 0.6);
    color: rgba(226, 232, 240, 0.9);
    font-size: 0.85rem;
    text-decoration: none;
    transition: all 0.2s ease;
}

.footer-links a i {
    font-size: 0.8rem;
}

.footer-links a:hover {
    background: rgba(15, 23, 42, 0.9);
    border-color: rgba(129, 140, 248, 0.9);
    color: #e5e7eb;
}

/* アニメーション */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

section {
    animation: fadeInUp 0.6s ease-out backwards;
}

section:nth-child(1) {
    animation-delay: 0.1s;
}

section:nth-child(2) {
    animation-delay: 0.2s;
}

section:nth-child(3) {
    animation-delay: 0.3s;
}

section:nth-child(4) {
    animation-delay: 0.4s;
}

/* レスポンシブデザイン */
@media (max-width: 768px) {
    header h1 {
        font-size: 2rem;
    }

    header p {
        font-size: 1rem;
    }

    main {
        grid-template-columns: 1fr;
        padding: 0 1rem 2rem;
    }

    section {
        padding: 1.5rem;
    }
}

@media (max-width: 480px) {
    header {
        padding: 1.5rem 1rem;
    }

    header h1 {
        font-size: 1.75rem;
    }

    section h2 {
        font-size: 1.25rem;
    }
}

@media (min-width: 900px) {
    main {
        grid-template-columns: 1fr;
    }
    
    .article-columns {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* コンテンツカテゴリのスタイル */
.content-category {
    margin-bottom: 2.5rem;
    padding-bottom: 2rem;
    border-bottom: 2px solid var(--border-color);
}

.content-category:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}

.content-category h3 {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.content-category h3 a {
    color: var(--text-primary);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    transition: all 0.2s ease;
}

.content-category h3 a:hover {
    color: var(--primary-color);
}

.content-category h3 i {
    color: var(--primary-color);
    font-size: 1.2rem;
}

.content-category h3 a .link-icon {
    font-size: 0.9rem;
    opacity: 0.7;
    margin-left: 0.25rem;
    transition: all 0.2s ease;
}

.content-category h3 a:hover .link-icon {
    opacity: 1;
    transform: translate(2px, -2px);
}

.category-description {
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 1.5rem;
    padding-left: 1rem;
    border-left: 3px solid var(--primary-color);
}

/* セクション内の直接のcategory-description（ブログセクション用） */
section > .category-description {
    margin-top: 1rem;
}

section h3 {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-top: 1.5rem;
    margin-bottom: 1rem;
}

.article-columns {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
    margin-top: 1.5rem;
}

.article-column h4 {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-top: 0;
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--border-color);
}

.article-list {
    list-style: none;
    margin-top: 0;
}

.article-list li {
    margin-bottom: 1.25rem;
    padding: 1rem;
    background: var(--light-bg);
    border-radius: 0.5rem;
    transition: all 0.2s ease;
}

.article-list li:hover {
    background: rgba(99, 102, 241, 0.05);
    transform: translateX(5px);
}

.article-list li a {
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
    display: block;
}

.article-list li p {
    margin-top: 0.5rem;
    margin-bottom: 0;
    font-size: 0.9rem;
    color: var(--text-secondary);
    padding-left: 1.5rem;
}