/* ===========================================
   ナレッジカテゴリ - デジタルライブラリ/マガジン風デザイン
   図書館のカード目録や洗練された雑誌記事のような
   エレガントで温かみのあるレイアウト
   =========================================== */

:root {
    --kn-bg: #faf7f2;
    --kn-bg-hero: #2c2417;
    --kn-bg-hero-surface: #3d3225;
    --kn-bg-content: #ffffff;
    --kn-bg-sidebar: #faf7f2;
    --kn-bg-warm: #fef9ef;
    --kn-border: #e8dcc8;
    --kn-border-light: #f0e6d2;
    --kn-border-hero: #5c4f3d;
    --kn-text: #2c2417;
    --kn-text-secondary: #5c4f3d;
    --kn-text-muted: #9c8e7a;
    --kn-text-hero: #f5efe6;
    --kn-text-hero-muted: #b8a98e;
    --kn-amber: #d4a020;
    --kn-amber-light: #f5e6b8;
    --kn-amber-subtle: rgba(212, 160, 32, 0.1);
    --kn-amber-dark: #b8860b;
    --kn-green: #10b981;
    --kn-green-light: #ecfdf5;
    --kn-rust: #c4704b;
    --kn-rust-light: #fdf2ec;
    --kn-navy: #3b5998;
}

/* ===== ヒーローセクション ===== */
.knowledge-hero {
    background: var(--kn-bg-hero);
    padding: 0 0 56px;
    position: relative;
    overflow: hidden;
}

.knowledge-hero::before {
    content: '';
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse 60% 50% at 20% 80%, rgba(212, 160, 32, 0.08), transparent),
        radial-gradient(ellipse 50% 40% at 80% 20%, rgba(196, 112, 75, 0.06), transparent);
    pointer-events: none;
}

.knowledge-hero__container {
    max-width: 800px;
    margin: 0 auto;
    padding: 0 24px;
    position: relative;
    z-index: 1;
}

/* アクセントライン */
.knowledge-hero__accent-line {
    height: 4px;
    background: linear-gradient(90deg,
        var(--kn-amber),
        var(--kn-rust),
        var(--kn-amber));
    margin-bottom: 0;
}

/* トップバー */
.knowledge-hero__topbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 24px 0 20px;
    border-bottom: 1px solid var(--kn-border-hero);
    margin-bottom: 40px;
}

.knowledge-hero__category-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.knowledge-hero__category-icon {
    display: inline-flex;
    color: var(--kn-amber);
}

.knowledge-hero__category-icon svg {
    stroke: var(--kn-amber);
}

.knowledge-hero__cat-link {
    font-family: 'Noto Sans JP', sans-serif;
    font-size: 12px;
    font-weight: 600;
    color: var(--kn-amber);
    text-decoration: none;
    padding: 4px 14px;
    background: rgba(212, 160, 32, 0.1);
    border: 1px solid rgba(212, 160, 32, 0.25);
    border-radius: 20px;
    transition: all 0.2s;
    letter-spacing: 0.03em;
}

.knowledge-hero__cat-link:hover {
    background: var(--kn-amber);
    border-color: var(--kn-amber);
    color: #ffffff;
}

.knowledge-hero__reading-time {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 12px;
    color: var(--kn-text-hero-muted);
}

.knowledge-hero__reading-time svg {
    stroke: var(--kn-text-hero-muted);
}

/* タイトルブロック */
.knowledge-hero__title-block {
    margin-bottom: 36px;
    text-align: center;
}

.knowledge-hero__title {
    font-family: 'Noto Sans JP', serif;
    font-size: 34px;
    font-weight: 800;
    color: var(--kn-text-hero);
    line-height: 1.5;
    margin: 0 0 24px;
    letter-spacing: 0.02em;
}

.knowledge-hero__subtitle-line {
    width: 60px;
    height: 3px;
    background: linear-gradient(90deg, var(--kn-amber), var(--kn-rust));
    margin: 0 auto;
    border-radius: 2px;
}

/* 著者・日付カード */
.knowledge-hero__info-card {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 24px 28px;
    background: var(--kn-bg-hero-surface);
    border: 1px solid var(--kn-border-hero);
    border-radius: 16px;
    margin-bottom: 24px;
}

.knowledge-hero__author {
    display: flex;
    align-items: center;
    gap: 14px;
}

.knowledge-hero__author-avatar img {
    width: 52px;
    height: 52px;
    border-radius: 50%;
    border: 3px solid var(--kn-border-hero);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

.knowledge-hero__author-detail {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.knowledge-hero__author-label {
    font-size: 10px;
    font-weight: 600;
    color: var(--kn-text-hero-muted);
    text-transform: uppercase;
    letter-spacing: 0.1em;
}

.knowledge-hero__author-name {
    font-family: 'Noto Sans JP', sans-serif;
    font-size: 15px;
    font-weight: 700;
    color: var(--kn-text-hero);
}

.knowledge-hero__dates {
    display: flex;
    gap: 28px;
}

.knowledge-hero__date-item {
    display: flex;
    flex-direction: column;
    gap: 3px;
    text-align: right;
}

.knowledge-hero__date-label {
    font-size: 10px;
    font-weight: 600;
    color: var(--kn-text-hero-muted);
    text-transform: uppercase;
    letter-spacing: 0.08em;
}

.knowledge-hero__date-value {
    font-size: 13px;
    color: var(--kn-text-hero);
    font-weight: 500;
}

/* タグ */
.knowledge-hero__tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    justify-content: center;
}

.knowledge-hero__tag {
    font-size: 12px;
    color: var(--kn-text-hero-muted);
    text-decoration: none;
    padding: 4px 14px;
    border: 1px solid var(--kn-border-hero);
    border-radius: 20px;
    transition: all 0.2s;
}

.knowledge-hero__tag:hover {
    color: var(--kn-amber);
    border-color: var(--kn-amber);
    background: rgba(212, 160, 32, 0.1);
}

/* ===== ページ全体の背景 ===== */
.single-wrapper--knowledge {
    background: var(--kn-bg);
}

/* ===== レイアウト ===== */
.article-main--knowledge {
    max-width: 1440px;
    margin: 0 auto;
    padding: 0 24px 48px;
}

.article-body--knowledge {
    background: var(--kn-bg-content);
    border: 1px solid var(--kn-border);
    border-radius: 16px;
    box-shadow:
        0 1px 3px rgba(44, 36, 23, 0.04),
        0 8px 32px rgba(44, 36, 23, 0.06);
    max-width: 820px;
    padding: 0;
    overflow: hidden;
    position: relative;
}

.article-body--knowledge::before {
    content: '';
    display: block;
    height: 5px;
    background: linear-gradient(90deg,
        var(--kn-amber),
        var(--kn-rust),
        var(--kn-amber));
}

.article-body--knowledge .article-content {
    padding: clamp(26px, 3.2vw, 44px);
}

/* ===== 記事本文カスタマイズ ===== */
.single-wrapper--knowledge .article-content h2 {
    font-family: 'Noto Sans JP', serif;
    font-size: 24px;
    font-weight: 800;
    color: var(--kn-text);
    margin-top: 56px;
    margin-bottom: 24px;
    padding: 20px 24px;
    background: var(--kn-bg-warm);
    border-radius: 12px;
    position: relative;
    line-height: 1.5;
}

.single-wrapper--knowledge .article-content h2::before {
    content: '';
    position: absolute;
    left: 0;
    top: 12px;
    bottom: 12px;
    width: 5px;
    background: linear-gradient(180deg, var(--kn-amber), var(--kn-rust));
    border-radius: 0 3px 3px 0;
}

.single-wrapper--knowledge .article-content h3 {
    font-family: 'Noto Sans JP', serif;
    font-size: 19px;
    font-weight: 700;
    color: var(--kn-text);
    margin-top: 40px;
    margin-bottom: 16px;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--kn-border);
    position: relative;
}

.single-wrapper--knowledge .article-content h3::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 40px;
    height: 2px;
    background: var(--kn-amber);
}

.single-wrapper--knowledge .article-content h4 {
    font-family: 'Noto Sans JP', sans-serif;
    font-size: 16px;
    font-weight: 700;
    color: var(--kn-text-secondary);
    margin-top: 32px;
    margin-bottom: 12px;
    padding-left: 14px;
    border-left: 3px solid var(--kn-amber-light);
}

.single-wrapper--knowledge .article-content p {
    color: var(--kn-text-secondary);
    line-height: 2;
    font-size: 15.5px;
    font-family: 'Noto Sans JP', sans-serif;
}

.single-wrapper--knowledge .article-content a {
    color: var(--kn-rust);
    text-decoration: none;
    border-bottom: 1px solid rgba(196, 112, 75, 0.3);
    transition: all 0.2s;
    font-weight: 500;
}

.single-wrapper--knowledge .article-content a:hover {
    color: var(--kn-amber-dark);
    border-bottom-color: var(--kn-amber-dark);
}

.single-wrapper--knowledge .article-content strong {
    color: var(--kn-text);
    font-weight: 700;
    background: linear-gradient(transparent 60%, var(--kn-amber-light) 60%);
}

.single-wrapper--knowledge .article-content code {
    font-family: 'JetBrains Mono', ui-monospace, monospace;
    background: var(--kn-bg-warm);
    border: 1px solid var(--kn-border);
    border-radius: 5px;
    padding: 2px 7px;
    font-size: 0.85em;
    color: var(--kn-rust);
}

.single-wrapper--knowledge .article-content pre {
    background: var(--kn-bg-hero) !important;
    border: 1px solid var(--kn-border);
    border-radius: 12px;
    position: relative;
    box-shadow: 0 4px 12px rgba(44, 36, 23, 0.08);
}

.single-wrapper--knowledge .article-content pre::before {
    content: '';
    display: block;
    height: 36px;
    background: var(--kn-bg-hero-surface);
    border-bottom: 1px solid var(--kn-border-hero);
    border-radius: 12px 12px 0 0;
    margin: -16px -16px 16px;
    padding: 0 16px;
    background-image:
        radial-gradient(circle at 20px 50%, #c4704b 4px, transparent 4px),
        radial-gradient(circle at 38px 50%, #d4a020 4px, transparent 4px),
        radial-gradient(circle at 56px 50%, #10b981 4px, transparent 4px);
    background-repeat: no-repeat;
}

.single-wrapper--knowledge .article-content pre code {
    background: transparent;
    border: none;
    padding: 0;
    color: #e8dcc8;
}

.single-wrapper--knowledge .article-content blockquote {
    border: none;
    background: var(--kn-bg-warm);
    padding: 24px 28px 24px 56px;
    margin: 32px 0;
    border-radius: 12px;
    color: var(--kn-text-secondary);
    font-style: italic;
    line-height: 1.9;
    position: relative;
    box-shadow: inset 0 0 0 1px var(--kn-border);
}

.single-wrapper--knowledge .article-content blockquote::before {
    content: '\201C';
    position: absolute;
    left: 18px;
    top: 8px;
    font-size: 48px;
    font-family: Georgia, 'Times New Roman', serif;
    color: var(--kn-amber);
    line-height: 1;
    opacity: 0.5;
}

.single-wrapper--knowledge .article-content ul,
.single-wrapper--knowledge .article-content ol {
    padding-left: 24px;
}

.single-wrapper--knowledge .article-content li {
    line-height: 2;
    color: var(--kn-text-secondary);
    margin-bottom: 4px;
}

.single-wrapper--knowledge .article-content li::marker {
    color: var(--kn-amber);
}

.single-wrapper--knowledge .article-content table {
    width: 100%;
    border-collapse: collapse;
    margin: 28px 0;
    font-size: 14px;
    border-radius: 8px;
    overflow: hidden;
    border: 1px solid var(--kn-border);
}

.single-wrapper--knowledge .article-content table th {
    background: var(--kn-bg-hero);
    color: var(--kn-text-hero);
    font-weight: 600;
    text-align: left;
    padding: 12px 16px;
    font-size: 13px;
    border-bottom: 2px solid var(--kn-amber);
}

.single-wrapper--knowledge .article-content table td {
    padding: 12px 16px;
    border-bottom: 1px solid var(--kn-border);
    color: var(--kn-text-secondary);
}

.single-wrapper--knowledge .article-content table tr:hover td {
    background: var(--kn-bg-warm);
}

.single-wrapper--knowledge .article-content img {
    border-radius: 12px;
    border: 1px solid var(--kn-border);
    box-shadow: 0 4px 16px rgba(44, 36, 23, 0.08);
}

.single-wrapper--knowledge .article-content hr {
    border: none;
    height: 1px;
    background: var(--kn-border);
    margin: 48px 0;
    position: relative;
}

.single-wrapper--knowledge .article-content hr::before {
    content: '***';
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
    background: var(--kn-bg-content);
    padding: 0 16px;
    color: var(--kn-text-muted);
    letter-spacing: 0.3em;
    font-size: 14px;
}

/* ===== サイドバー ===== */
.article-sidebar--knowledge {
    background: transparent;
    position: sticky;
    top: 100px;
    align-self: start;
    max-height: calc(100vh - 120px);
    overflow-y: auto;
    scrollbar-width: thin;
    scrollbar-color: var(--kn-border) transparent;
}

/* サイドバーセクション */
.knowledge-sidebar__section {
    margin-top: 24px;
    background: var(--kn-bg-content);
    border: 1px solid var(--kn-border);
    border-radius: 16px;
    padding: 20px;
    box-shadow: 0 2px 8px rgba(44, 36, 23, 0.04);
}

.knowledge-sidebar__section-title {
    display: flex;
    align-items: center;
    gap: 8px;
    font-family: 'Noto Sans JP', sans-serif;
    font-size: 12px;
    font-weight: 700;
    color: var(--kn-text-muted);
    letter-spacing: 0.05em;
    margin: 0 0 14px;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--kn-border-light);
}

.knowledge-sidebar__section-title svg {
    stroke: var(--kn-text-muted);
}

/* チップ */
.knowledge-sidebar__chips {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.knowledge-sidebar__chip {
    font-size: 12px;
    color: var(--kn-text-secondary);
    text-decoration: none;
    padding: 4px 12px;
    border: 1px solid var(--kn-border);
    border-radius: 20px;
    transition: all 0.2s;
}

.knowledge-sidebar__chip:hover {
    color: var(--kn-amber-dark);
    border-color: var(--kn-amber);
    background: var(--kn-amber-subtle);
}

.knowledge-sidebar__chip--category {
    color: var(--kn-amber-dark);
    background: var(--kn-amber-subtle);
    border-color: rgba(212, 160, 32, 0.25);
    font-weight: 600;
}

.knowledge-sidebar__chip--category:hover {
    background: var(--kn-amber);
    border-color: var(--kn-amber);
    color: #ffffff;
}

.knowledge-sidebar__empty {
    font-size: 12px;
    color: var(--kn-text-muted);
    font-style: italic;
}

/* 関連ナレッジ */
.knowledge-sidebar__related-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.knowledge-sidebar__related-item {
    border-bottom: 1px solid var(--kn-border-light);
}

.knowledge-sidebar__related-item:last-child {
    border-bottom: none;
}

.knowledge-sidebar__related-link {
    display: flex;
    flex-direction: column;
    gap: 4px;
    padding: 12px 4px;
    text-decoration: none;
    transition: all 0.2s;
    border-radius: 8px;
}

.knowledge-sidebar__related-link:hover {
    background: var(--kn-amber-subtle);
    padding-left: 12px;
}

.knowledge-sidebar__related-title {
    font-size: 13px;
    color: var(--kn-text);
    line-height: 1.5;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    font-weight: 500;
}

.knowledge-sidebar__related-link:hover .knowledge-sidebar__related-title {
    color: var(--kn-amber-dark);
}

.knowledge-sidebar__related-date {
    font-size: 11px;
    color: var(--kn-text-muted);
}

/* ===== ナビゲーション ===== */
.post-navigation--knowledge {
    background: var(--kn-bg-hero);
    border-top: none;
    padding-top: 56px;
    padding-bottom: 72px;
    position: relative;
}

.post-navigation--knowledge::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg,
        var(--kn-amber),
        var(--kn-rust),
        var(--kn-amber));
}

.post-navigation--knowledge .post-navigation__container {
    position: relative;
    z-index: 1;
}

.post-navigation--knowledge .post-navigation__item {
    border: 1px solid var(--kn-border-hero);
    background: var(--kn-bg-hero-surface);
    padding: 24px;
    border-radius: 16px;
    transition: all 0.3s;
}

.post-navigation--knowledge .post-navigation__item:hover {
    border-color: var(--kn-amber);
    background: rgba(212, 160, 32, 0.08);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
}

.post-navigation--knowledge .post-navigation__direction {
    color: var(--kn-text-hero-muted);
    font-size: 11px;
    letter-spacing: 0.03em;
}

.post-navigation--knowledge .post-navigation__title {
    color: var(--kn-text-hero);
}

.post-navigation--knowledge .post-navigation__item:hover .post-navigation__title {
    color: var(--kn-amber);
}

.post-navigation--knowledge .post-navigation__arrow svg {
    stroke: var(--kn-text-hero-muted);
}

.post-navigation--knowledge .post-navigation__item:hover .post-navigation__arrow svg {
    stroke: var(--kn-amber);
}

/* ===== レスポンシブ ===== */
@media (max-width: 960px) {
    .article-main--knowledge {
        padding: 32px 20px;
    }

    .article-sidebar--knowledge {
        position: static;
        max-height: none;
    }
}

@media (max-width: 768px) {
    .knowledge-hero__title {
        font-size: 26px;
    }

    .knowledge-hero__info-card {
        flex-direction: column;
        gap: 20px;
        align-items: flex-start;
        padding: 20px;
    }

    .knowledge-hero__dates {
        gap: 20px;
    }

    .knowledge-hero__date-item {
        text-align: left;
    }

    .knowledge-hero__topbar {
        flex-direction: column;
        gap: 12px;
        align-items: flex-start;
    }

    .article-body--knowledge .article-content {
        padding: clamp(16px, 3vw, 28px);
    }

    .post-navigation--knowledge {
        padding-top: 40px;
        padding-bottom: 56px;
    }

    .post-navigation--knowledge .post-navigation__item {
        padding: 20px;
    }
}

@media (max-width: 480px) {
    .knowledge-hero__title {
        font-size: 22px;
    }

    .knowledge-hero__dates {
        flex-direction: column;
        gap: 12px;
    }

    .article-body--knowledge .article-content {
        padding: clamp(14px, 2.5vw, 20px);
    }

    .knowledge-hero__tags {
        justify-content: flex-start;
    }
}