/* ============================================
   リセット
   ============================================ */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html,
body {
    margin: 0;
    padding: 0;
}

html {
    background-color: var(--color-bg);
}

/* ============================================
   CSS変数定義
   ============================================ */
/* Light Mode (デフォルト) */
:root {
    /* 色 */
    --color-primary: #0e288f;
    --color-transparent: rgba(209, 218, 253, 0.5);
    --color-header-footer-bg: #0e288f;
    --color-header-footer-text: #ffffff;
    --color-text: #000000;
    --color-text-inverse: #ffffff;
    --color-bg: #ffffff;
    --shadow-color: rgba(0, 0, 0, 0.7);

    /* フォント */
    --font-family-base: sans-serif;
    --font-family-heading: "Courier New", Courier, monospace;
    --font-family-default: "YuMincho", "Yu Mincho", YuMincho, "Hiragino Mincho ProN", "Hiragino Mincho Pro", "Hiragino Mincho", "Noto Serif JP", "Noto Serif CJK JP", serif;
}

/* Dark Mode */
[data-theme="dark"] {
    /* 色 */
    --color-primary: #4c8bff;
    --color-transparent: rgba(14, 40, 143, 0.5);
    --color-header-footer-bg: #0e288f;
    --color-header-footer-text: #ffffff;
    --color-text: #ffffff;
    --color-text-inverse: #000000;
    --color-bg: #1a1a1a;
    --shadow-color: rgba(136, 136, 136, 0.7);

    /* フォント */
    --font-family-base: sans-serif;/*"Courier New", Courier, monospace;*/
    --font-family-default: "YuMincho", "Yu Mincho", YuMincho, "Hiragino Mincho ProN", "Hiragino Mincho Pro", "Hiragino Mincho", "Noto Serif JP", "Noto Serif CJK JP", serif;
}

/* ============================================
   基本レイアウト
   ============================================ */
body {
    position: relative;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    background-color: transparent;
    color: var(--color-text);
    font-family: var(--font-family-default);
}

/* 擬似要素を使って固定背景を実装（iOS Safari対応） */
body::before {
    content: "";
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: var(--bg-image, none);
    background-repeat: no-repeat;
    background-position: center;
    background-size: 40vh;
    z-index: -1;
}

main {
    padding: 1em 5vw 1em 5vw;
    flex: 1;
}

/* ============================================
   Header
   ============================================ */
#header-top {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    align-items: center;
    padding: 2em 1em 0em 1em;
    position: relative;
}

.site-title {
    font-family: "Courier New";
    text-align: center;
    grid-column: 2;
    justify-self: center;
    color: var(--color-primary);
}

.site-title a {
    text-decoration: none;
    color: inherit;
}

.theme-toggle {
    grid-column: 3;
    justify-self: end;
    background: none;
    border: 2px solid var(--color-primary);
    color: var(--color-primary);
    width: 1.7em;
    height: 1.7em;
    padding: 0;
    cursor: pointer;
    font-size: 1.2em;
    border-radius: 50%;
    margin-left: auto;
    transition: all 0.3s ease;
    z-index: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.theme-toggle:hover {
    background-color: var(--color-primary);
    color: var(--color-text-inverse);
}

.theme-icon {
    display: block;
    width: 1em;
    height: 1em;
    fill: currentColor;
}

/* ============================================
   Navigation
   ============================================ */
#site-nav {
    padding: 0.5em;
    margin: 0em;
    background-color: var(--color-header-footer-bg);
    font-family: var(--font-family-heading);
    color: var(--color-header-footer-text);
}

#site-nav ul {
    list-style: none;
    display: flex;
    justify-content: center;
    gap: 1.5em;
    padding: 0;
    margin: 0;
}

#site-nav a {
    color: inherit;
    text-decoration: none;
    display: inline-flex;
    align-items: flex-end;
    gap: 0.3em;
    padding: 0.2em;
    border-bottom: 1px solid transparent;
    transition: border-bottom-color 0.3s ease;
}

#site-nav a:hover {
    border-bottom: 1px solid var(--color-header-footer-text);
}

#site-nav .nav-item.active>a {
    border-bottom: 1px solid var(--color-header-footer-text);
}

.nav-icon {
    height: 1em;
    width: auto;
    display: inline-block;
    align-self: flex-start;
    margin-bottom: -0.15em;
}

/* ============================================
   Footer
   ============================================ */
footer {
    background-color: var(--color-header-footer-bg);
    padding: 2em 1em 2em 1em;
    line-height: 1.5em;
    text-align: center;
    font-size: 0.9rem;
    color: var(--color-header-footer-text);
    font-family: var(--font-family-base);
}

footer a {
    color: inherit;
    text-decoration: none;
}

#sns-nav {
    display: flex;
    justify-content: center;
    gap: 1em;
    margin: 1em 0;
}

#sns-nav ul {
    list-style: none;
    display: flex;
    justify-content: center;
    gap: 1em;
    padding: 0;
    margin: 0;
}

.sns-icon {
    width: 1.5em;
    height: 1.5em;
    display: block;
}

/* ============================================
   タイポグラフィ
   ============================================ */
.site-title {
    font-family: var(--font-family-heading);
}

.site-title .initial {
    font-size: 2em;
    vertical-align: baseline;
    display: inline;
    color: transparent;
    -webkit-text-stroke: 0.05em var(--color-primary);
}

.section-title {
    font-family: var(--font-family-base);
    margin-bottom: 0.5em;
}

.section-title .initial {
    font-size: 1.5em;
    vertical-align: baseline;
    display: inline;
    color: var(--color-primary);
}

.page-title .initial {
    font-size: 1.5em;
    vertical-align: baseline;
    display: inline;
    color: var(--color-primary);
}

.article-title .initial {
    font-size: 1.5em;
    vertical-align: baseline;
    display: inline;
    color: var(--color-primary);
}

h1 .initial,
h2 .initial {
    font-size: 1.5em;
    vertical-align: baseline;
    display: inline;
    color: var(--color-primary);
}

/* ============================================
   Components: content-block (共通構造)
   ============================================ */
.content-block {
    margin-bottom: 2em;
}

.content-block-title {
    font-family: var(--font-family-base);
    font-size: 1.3em;
    margin-bottom: 1em;
    color: var(--color-text);
}

.content-block-title .initial {
    font-size: 1.5em;
    vertical-align: baseline;
    display: inline;
    color: var(--color-primary);
}

.content-block-body {
    padding: 0em 0em 0em 1em;
}

/* ============================================
   Components: btn-outline (共通ボタンスタイル)
   ============================================ */
.btn-outline {
    color: var(--color-primary);
    text-decoration: none;
    padding: 0.5em 1em;
    border: 2px solid var(--color-primary);
    border-radius: 0.4em;
    transition: all 0.3s ease;
    display: inline-block;
}

.btn-outline:hover {
    background-color: var(--color-primary);
    color: var(--color-text-inverse);
    text-decoration: none;
}

/* ============================================
   Components: page-item / page-list
   ============================================ */
.page-list {
    list-style: none;
}

.page-item {
    background-color: var(--color-transparent);
    color: var(--color-text);
    margin: 1em auto;
    padding: 0.8em 1.5em 0.8em 1.5em;
    box-shadow: 0.1em 0.1em 0.2em var(--shadow-color);
    border-radius: 0.1em;
    text-shadow: none;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.page-item:hover {
    transform: translateY(-0.3em);
    box-shadow: 0.2em 0.3em 0.4em var(--shadow-color);
}

.page-item .page-link {
    text-decoration: none;
    color: var(--color-text);
    font-family: var(--font-family-base);
}

.page-item hr {
    border: 0.8px solid var(--color-text);
    margin: 0.2em 0em 0.5em 0em;
}

.page-header {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    flex-wrap: wrap;
    gap: 0.4em 1em;
    margin-bottom: 0em;
}

.page-title {
    font-family: var(--font-family-base);
    margin: 0;
    flex: 1 1 auto;
    min-width: 0;
    overflow-wrap: anywhere;
    word-break: break-word;
}

.page-date {
    flex: 0 0 auto;
    margin-left: auto;
    font-family: var(--font-family-base);
    font-size: 0.9em;
}

.page-description {
    font-family: var(--font-family-default);
}

/* ============================================
   Components: suggest-section
   ============================================ */
.suggest-section {
    margin-bottom: 2rem;
    width: 100%;
    max-width: 600px;
}

.suggest-label {
    font-size: 0.9em;
    margin-bottom: 1rem;
    opacity: 0.8;
}

.suggest-links {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1em;
}

.suggest-link {
    display: grid;
    align-items: center;
    font-size: 0.9em;
    padding: 0.8em 1em;
}

.suggest-link-content {
    display: grid;
    grid-template-rows: auto 1fr;
    height: 100%;
    justify-items: center;
}

.suggest-link-title {
    display: flex;
    align-items: center;
    font-size: 1em;
}

.suggest-link-label {
    font-size: 0.8em;
    opacity: 0.8;
    margin-bottom: 0.5em;
}

/* ============================================
   Components: pdf-view
   ============================================ */
.pdf-view-container {
    margin: 2em 0;
}

/* ============================================
   Components: pdf-embed
   ============================================ */
.pdf-embed-container {
    margin: 1em 0;
    width: 100%;
    position: relative;
    overflow: hidden;
}

.pdf-embed {
    width: 100%;
    height: 800px;
    display: block;
}

/* ============================================
   Components: pdf-link
   ============================================ */
.pdf-link-container {
    font-family: var(--font-family-base);
    margin: 1em 0;
}

.pdf-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5em;
    padding: 0.2em 1em;
    border: 1px solid var(--color-text);
    border-radius: 0.4em;
    text-decoration: none !important;
    color: var(--color-text);
    transition: all 0.3s ease;
    background-color: var(--color-bg);
    width: 100%;
    min-height: 4em;
}

.pdf-link:link,
.pdf-link:visited,
.pdf-link:active {
    text-decoration: none !important;
    color: var(--color-text);
}

.pdf-link:hover {
    background-color: var(--color-text);
    color: var(--color-text-inverse) !important;
    text-decoration: none !important;
}

/* ダークモードでもホバー時に色が変わるように */
[data-theme="dark"] .pdf-link:hover {
    background-color: var(--color-text);
    color: var(--color-text-inverse);
}

/* ホバー時にアイコンを逆の色に変更 */
/* ライトモード: 黒 → 白 */
.pdf-link:hover .pdf-link-icon {
    filter: brightness(0) invert(1);
}

/* ダークモード: 白 → 黒 */
[data-theme="dark"] .pdf-link:hover .pdf-link-icon {
    filter: brightness(0);
}

.pdf-link-icon {
    width: 16px;
    height: 16px;
    flex-shrink: 0;
    transition: filter 0.3s ease;
    filter: brightness(0);
}

[data-theme="dark"] .pdf-link-icon {
    filter: brightness(0) invert(1);
}

.pdf-link-filename {
    font-size: 0.9em;
    flex: 1;
    text-align: left;
}

.pdf-link-download {
    font-size: 0.85em;
    padding: 0.4em 0.8em;
    border-radius: 0.3em;
    background-color: var(--color-text);
    color: var(--color-text-inverse);
    transition: background-color 0.3s ease, color 0.3s ease;
    white-space: nowrap;
}

.pdf-link:hover .pdf-link-download {
    background-color: var(--color-text-inverse);
    color: var(--color-text);
}

/* ============================================
   Components: youtube-embed
   ============================================ */
.youtube-embed-container {
    margin: 1em 0;
    position: relative;
    width: 100%;
    aspect-ratio: 16 / 9;
}

.youtube-embed {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    border: 0;
    display: block;
}

/* ============================================
   Components: link
   ============================================ */
.link-container {
    font-family: var(--font-family-base);
    margin: 1em 0;
}

.link {
    display: inline-flex;
    align-items: center;
    gap: 0.5em;
    padding: 0.2em 1em;
    border: 1px solid var(--color-text);
    border-radius: 0.4em;
    text-decoration: none !important;
    color: var(--color-text);
    transition: all 0.3s ease;
    background-color: var(--color-bg);
    width: 100%;
    min-height: 4em;
}

.link:link,
.link:visited,
.link:active {
    text-decoration: none !important;
    color: var(--color-text);
}

.link:hover {
    background-color: var(--color-text);
    color: var(--color-text-inverse) !important;
    text-decoration: none !important;
}

/* ダークモードでもホバー時に色が変わるように */
[data-theme="dark"] .link:hover {
    background-color: var(--color-text);
    color: var(--color-text-inverse);
}

/* ホバー時にアイコンを逆の色に変更 */
/* ライトモード: 黒 → 白 */
.link:hover .link-icon {
    filter: brightness(0) invert(1);
}

/* ダークモード: 白 → 黒 */
[data-theme="dark"] .link:hover .link-icon {
    filter: brightness(0);
}

.link-icon {
    width: 16px;
    height: 16px;
    flex-shrink: 0;
    transition: filter 0.3s ease;
    filter: brightness(0);
}

[data-theme="dark"] .link-icon {
    filter: brightness(0) invert(1);
}

.link-filename {
    font-size: 0.9em;
    flex: 1;
    text-align: left;
}

.link-open {
    font-size: 0.85em;
    padding: 0.4em 0.8em;
    border-radius: 0.3em;
    background-color: var(--color-text);
    color: var(--color-text-inverse);
    transition: background-color 0.3s ease, color 0.3s ease;
    white-space: nowrap;
    text-align: center;
}

.link:hover .link-open {
    background-color: var(--color-text-inverse);
    color: var(--color-text);
}

/* ============================================
   Components: image-figure
   ============================================ */
.image-figure {
    margin: 1.5rem 0;
    text-align: center;
}

.image-figure img {
    max-width: 100%;
    height: auto;
}

.image-figure figcaption {
    margin-top: 0.5rem;
    font-size: 0.9em;
    color: var(--color-text);
    opacity: 0.8;
}

/* ============================================
   Home Page Styles
   ============================================ */
.home {
    max-width: 800px;
    margin: 0 auto;
    padding: 1em;
}

   .home-header {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    gap: 1em;
}

.home-lastmod {
    font-family: var(--font-family-base);
    font-size: 0.9em;
    color: var(--color-text);
    opacity: 0.7;
    flex-shrink: 0;
}

.home-lastmod time {
    font-family: var(--font-family-base);
}

/* ============================================
   Markdown Content Styles
   ============================================ */
/* 本文内で横幅を超える長い語を強制的に折り返す */
.article-content,
.markdown-content {
    overflow-wrap: anywhere;
    word-break: break-word;
}

/* 子要素にも折り返しを適用 */
.article-content *,
.markdown-content * {
    overflow-wrap: anywhere;
    word-break: break-word;
}

/* 箇条書きの直前のpタグのmargin-bottomを削除 */
.article-content p:has(+ ul),
.article-content p:has(+ ol),
.markdown-content p:has(+ ul),
.markdown-content p:has(+ ol) {
    margin-bottom: 0;
}

/* 見出しのスタイル */
.article-content h1,
.article-content h2,
.markdown-content h1,
.markdown-content h2 {
    font-family: var(--font-family-base);
}

.article-content h3,
.markdown-content h3 {
    margin-top: 0.5em;
}

/* リンクのスタイル */
.article-content a,
.markdown-content a {
    color: #777;
    text-decoration: underline;
}

.article-content a:hover,
.markdown-content a:hover {
    color: #666;
}

/* 引用のスタイル */
.article-content blockquote,
.markdown-content blockquote {
    margin: 1em 0;
    padding: 0.5em 1em;
    border-radius: 0.5em;
    background-color: rgba(178, 178, 178, 0.2);
}

/* 引用内の最後のpタグのmargin-bottomを削除 */
.article-content blockquote p:last-child,
.markdown-content blockquote p:last-child {
    margin-bottom: 0;
}

/* 画像のスタイル */
.article-content img,
.markdown-content img {
    display: block;
    margin: 1em auto;
    max-width: 50%;
    height: auto;
}

/* リストのスタイル */
.article-content ul,
.article-content ol,
.markdown-content ul,
.markdown-content ol {
    padding-left: 2em;
}

.article-content li,
.markdown-content li {
    margin-left: 0.5em;
}

/* 水平線のスタイル */
.article-content hr,
.markdown-content hr {
    margin: 1em 0;
    border: 0.5px solid var(--color-text);
}

/* ============================================
   Section(List) Page Styles
   ============================================ */
.section-container {
    max-width: 800px;
    margin: 0 auto;
    padding: 1em;
}

/* ============================================
   Single Page Styles
   ============================================ */
/* コンテナ */
.single {
    max-width: 800px;
    margin: 0 auto;
    padding: 1em;
}

/* 戻りリンク */
.article-back-nav {
    margin-bottom: 1em;
}

.back-link {
    font-size: 0.9em;
    font-family: var(--font-family-base);
}

/* ヘッダー */
.article-header {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    flex-wrap: wrap;
    gap: 0.5em 1em;
    margin-bottom: 1em;
    padding-bottom: 0.5em;
    border-bottom: 1px solid var(--color-text);
}

.article-title {
    font-family: var(--font-family-base);
    margin: 0;
    flex: 1 1 auto;
    min-width: 0;
}

.article-date {
    flex: 0 0 auto;
    font-family: var(--font-family-base);
    font-size: 0.9em;
    color: var(--color-text);
}

/* コンテンツコンテナ */
.article-content {
    font-family: var(--font-family-default);
    line-height: 1.8;
    color: var(--color-text);
}

.article-content p {
    margin-bottom: 1em;
}

/* ナビゲーション */
.article-nav {
    margin-top: 1em;
    padding-top: 1.5em;
    border-top: 1px solid var(--color-text);
}

.article-nav-links {
    display: grid;
    grid-template-columns: 1fr 1fr;
    align-items: stretch;
    gap: 1em;
}

/* ナビゲーションリンク共通 */
.article-nav .nav-link {
    font-size: 0.9em;
    display: grid;
    align-items: center;
    min-height: 100%;
    box-sizing: border-box;
}

/* 前の記事 */
.article-nav .prev-link {
    grid-column: 1;
    justify-self: start;
    grid-template-columns: auto 1fr;
    gap: 0.5em;
}

.article-nav .prev-arrow {
    grid-column: 1;
    align-self: center;
    padding-right: 0.7em;
}

.article-nav .prev-content {
    grid-column: 2;
    display: flex;
    flex-direction: column;
    gap: 0.2em;
}

.article-nav .prev-label {
    font-size: 0.8em;
}

.article-nav .prev-title {
    font-size: 1em;
}

/* 次の記事 */
.article-nav .next-link {
    grid-column: 2;
    justify-self: end;
    grid-template-columns: 1fr auto;
    gap: 0.5em;
}

.article-nav .next-content {
    grid-column: 1;
    display: flex;
    flex-direction: column;
    gap: 0.2em;
    text-align: right;
}

.article-nav .next-label {
    font-size: 0.8em;
}

.article-nav .next-title {
    font-size: 1em;
}

.article-nav .next-arrow {
    grid-column: 2;
    align-self: center;
    padding-left: 0.7em;
}

/* 記事ページ: おすすめセクション */
.article-suggest {
    margin-top: 1.5rem;
}

.article-suggest .suggest-label {
    text-align: center;
    margin-bottom: 1rem;
}

.article-suggest .suggest-links {
    max-width: 100%;
}

/* ============================================
   Pagination Styles
   ============================================ */
.pagination {
    margin: 2em auto;
    padding: 1em 0;
    text-align: center;
}

.pagination-links {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 1.5em;
    font-family: var(--font-family-base);
}

.pagination-link {
    display: flex;
    align-items: center;
    gap: 0.5em;
}

.pagination-link.disabled {
    color: var(--color-text);
    border-color: var(--color-text);
    opacity: 0.5;
    cursor: not-allowed;
    pointer-events: none;
}

.pagination-arrow {
    font-size: 1em;
}

.pagination-label {
    font-size: 0.9em;
}

.pagination-info {
    display: flex;
    align-items: center;
    gap: 0.3em;
    color: var(--color-text);
    font-size: 0.9em;
}

.pagination-current {
    font-weight: bold;
    color: var(--color-primary);
}

.pagination-separator {
    opacity: 0.5;
}

.pagination-total {
    opacity: 0.7;
}

/* ============================================
   404 Page Styles
   ============================================ */
.error-page {
    min-height: calc(100vh - 200px);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding: 2rem;
}

.error-page h1 {
    font-size: 2.5rem;
    margin-bottom: 0;
}

.error-page hr {
    width: 100%;
    max-width: 300px;
    margin: 0.5rem 0 1.5rem 0;
    border: none;
    border-top: 1px solid var(--color-text);
}

.error-page .error-message {
    margin-bottom: 6rem;
}

.error-page .suggest-section {
    max-width: 600px;
}

/* ============================================
   Responsive Styles (Mobile)
   ============================================ */
@media (max-width: 768px) {

    /* 基本レイアウト */
    main {
        padding: 1em 6vw 0em 6vw;
    }

    /* ヘッダー */
    #header-top {
        grid-template-columns: 1fr auto 1fr;
        padding: 1.5em 0.5em 0em 0.5em;
    }

    .site-title {
        font-size: 1.2em;
    }

    /* ナビゲーション */
    #site-nav ul {
        flex-direction: column;
        align-items: center;
        gap: 0.8em;
        font-size: 0.9em;
    }

    /* Single Page */
    .single {
        padding: 0.5em 0.5em 1.5em 0.5em;
    }

    .article-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.5em;
    }

    /* 記事ナビゲーション - モバイルでは縦並び */
    .article-nav-links {
        grid-template-columns: 1fr;
        gap: 0.8em;
    }

    .article-nav .prev-link {
        grid-column: 1;
        justify-self: stretch;
    }

    .article-nav .next-link {
        grid-column: 1;
        justify-self: stretch;
    }

    /* ページネーション */
    .pagination-links {
        flex-wrap: wrap;
        gap: 1em;
        font-size: 0.9em;
    }

    .pagination-link {
        padding: 0.4em 0.8em;
        font-size: 0.9em;
    }

    /* ページアイテム */
    .page-item {
        margin: 0.8em auto;
        padding: 0.6em 1em;
    }

    .page-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.3em;
    }

    .page-title {
        font-size: 0.9em;
    }

    .page-date {
        font-size: 0.85em;
    }

    /* 画像のスタイル - モバイルでは100% */
    .article-content img,
    .content-block-body img {
        max-width: 100%;
    }

    /* タイトル */
    .section-title .initial {
        font-size: 1.3em;
    }

    .page-title .initial {
        font-size: 1.3em;
    }

    .article-title .initial {
        font-size: 1.3em;
    }

    h1 .initial,
    h2 .initial,
    h3 .initial,
    h4 .initial,
    h5 .initial,
    h6 .initial {
        font-size: 1.3em;
    }

    .site-title .initial {
        font-size: 1.7em;
    }

    /* テーマ切り替えトグルボタン */
    .theme-toggle {
        width: 1.5em;
        height: 1.5em;
        font-size: 1.2em;
    }

    /* PDF埋め込み - モバイルでは高さを調整 */
    .pdf-embed {
        height: 500px;
        min-height: 400px;
    }

    /* モバイルではPDF埋め込みがうまく動作しない場合があるため、
       ダウンロードリンクを強調表示 */
    .pdf-embed-container {
        margin-bottom: 1.5em;
    }

    /* Suggest Section - モバイルでは縦並び */
    .suggest-links {
        grid-template-columns: 1fr;
    }

    /* コンテントブロック */
    .content-block-title {
        margin-bottom: 0.5em;
    }

    .content-block-body {
        padding: 0em 0em 0em 0em;
    }

    .pdf-view-container {
        margin: 0;
    }

    .pdf-embed-container {
        display: none;
    }
}