/* ===================================
   精密光學篩選管理系統 - 使用指南樣式
   GitBook 風格
   =================================== */

:root {
    --primary-color: #3182f6;
    --primary-dark: #1a73e8;
    --sidebar-bg: #f8f9fa;
    --sidebar-width: 280px;
    --toc-width: 220px;
    --header-height: 60px;
    --border-color: #e9ecef;
    --text-color: #333;
    --text-muted: #6c757d;
    --code-bg: #f4f4f4;
    --highlight-bg: #fff3cd;
}

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

body {
    font-family: "Microsoft JhengHei", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    line-height: 1.7;
    color: var(--text-color);
    background-color: #fff;
}

/* ===== 頂部導航 ===== */
.top-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    background: #fff;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 20px;
    z-index: 1000;
}

.header-left {
    display: flex;
    align-items: center;
    gap: 15px;
}

.sidebar-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 20px;
    color: var(--text-muted);
    cursor: pointer;
    padding: 8px;
}

.sidebar-toggle:hover {
    color: var(--primary-color);
}

.back-link {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 14px;
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    border-radius: 4px;
    transition: all 0.2s;
}

.back-link:hover {
    background: var(--sidebar-bg);
    color: var(--primary-color);
}

.site-title {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-color);
}

.header-right {
    display: flex;
    align-items: center;
}

.search-box {
    position: relative;
    width: 280px;
}

.search-box i {
    position: absolute;
    left: 12px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
}

.search-box input {
    width: 100%;
    padding: 10px 12px 10px 38px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 14px;
    transition: all 0.2s;
}

.search-box input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(49, 130, 246, 0.1);
}

/* ===== 主要佈局 ===== */
.main-container {
    display: flex;
    margin-top: var(--header-height);
    min-height: calc(100vh - var(--header-height));
}

/* ===== 側邊欄 ===== */
.sidebar {
    position: fixed;
    top: var(--header-height);
    left: 0;
    width: var(--sidebar-width);
    height: calc(100vh - var(--header-height));
    background: var(--sidebar-bg);
    border-right: 1px solid var(--border-color);
    overflow-y: auto;
    padding: 20px 0;
    transition: transform 0.3s ease;
    z-index: 900;
}

.sidebar.collapsed {
    transform: translateX(-100%);
}

.sidebar-nav {
    padding: 0 15px;
}

.nav-group {
    margin-bottom: 8px;
}

.nav-group-title {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
    font-weight: 600;
    color: var(--text-color);
    padding: 10px 12px;
    cursor: pointer;
    border-radius: 4px;
    transition: all 0.2s;
    user-select: none;
}

.nav-group-title:hover {
    background: rgba(49, 130, 246, 0.1);
}

.nav-group-title i {
    font-size: 10px;
    transition: transform 0.2s;
}

.nav-group.expanded .nav-group-title i {
    transform: rotate(90deg);
}

.nav-group-items {
    display: none;
    list-style: none;
    padding: 0;
    margin: 0 0 10px 0;
}

.nav-group.expanded .nav-group-items {
    display: block;
}

.nav-group-items li {
    margin: 0;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 8px 12px 8px 28px;
    color: var(--text-color);
    text-decoration: none;
    font-size: 14px;
    border-radius: 4px;
    transition: all 0.2s;
    cursor: pointer;
}

.nav-item i {
    width: 18px;
    text-align: center;
    color: var(--text-muted);
    font-size: 13px;
}

.nav-item:hover {
    background: rgba(49, 130, 246, 0.1);
    color: var(--primary-color);
}

.nav-item:hover i {
    color: var(--primary-color);
}

.nav-item.active {
    background: var(--primary-color);
    color: #fff;
}

.nav-item.active i {
    color: #fff;
}

/* ===== 主內容區 ===== */
.main-content {
    flex: 1;
    margin-left: var(--sidebar-width);
    margin-right: var(--toc-width);
    padding: 40px 60px;
    max-width: 100%;
    min-height: calc(100vh - var(--header-height));
    overflow-y: auto;
}

.content-area {
    max-width: 850px;
    margin: 0 auto;
}

/* ===== 文章內容樣式 ===== */
.content-area h1 {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 20px;
    padding-bottom: 15px;
    border-bottom: 2px solid var(--border-color);
}

.content-area h2 {
    font-size: 24px;
    font-weight: 600;
    margin-top: 40px;
    margin-bottom: 15px;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--border-color);
}

.content-area h3 {
    font-size: 20px;
    font-weight: 600;
    margin-top: 30px;
    margin-bottom: 12px;
}

.content-area h4 {
    font-size: 16px;
    font-weight: 600;
    margin-top: 25px;
    margin-bottom: 10px;
}

.content-area p {
    margin-bottom: 16px;
}

.content-area ul, .content-area ol {
    margin-bottom: 16px;
    padding-left: 25px;
}

.content-area li {
    margin-bottom: 8px;
}

.content-area li > ul, .content-area li > ol {
    margin-top: 8px;
    margin-bottom: 0;
}

.content-area a {
    color: var(--primary-color);
    text-decoration: none;
}

.content-area a:hover {
    text-decoration: underline;
}

.content-area code {
    background: var(--code-bg);
    padding: 2px 6px;
    border-radius: 3px;
    font-family: 'Consolas', 'Monaco', monospace;
    font-size: 14px;
}

.content-area pre {
    background: #2d2d2d;
    color: #f8f8f2;
    padding: 20px;
    border-radius: 8px;
    overflow-x: auto;
    margin-bottom: 20px;
}

.content-area pre code {
    background: none;
    padding: 0;
    color: inherit;
}

.content-area blockquote {
    border-left: 4px solid var(--primary-color);
    background: var(--sidebar-bg);
    padding: 15px 20px;
    margin: 20px 0;
    border-radius: 0 8px 8px 0;
}

.content-area blockquote p:last-child {
    margin-bottom: 0;
}

.content-area table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
}

.content-area table th,
.content-area table td {
    padding: 12px 15px;
    border: 1px solid var(--border-color);
    text-align: left;
}

.content-area table th {
    background: var(--sidebar-bg);
    font-weight: 600;
}

.content-area table tr:hover {
    background: #fafafa;
}

.content-area img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    margin: 20px 0;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

/* 提示框 */
.tip, .warning, .danger, .info {
    padding: 15px 20px;
    border-radius: 8px;
    margin: 20px 0;
    display: flex;
    gap: 12px;
}

.tip::before, .warning::before, .danger::before, .info::before {
    font-family: 'Font Awesome 6 Free';
    font-weight: 900;
    font-size: 18px;
}

.tip {
    background: #d4edda;
    border-left: 4px solid #28a745;
    color: #155724;
}

.tip::before {
    content: '\f058';
    color: #28a745;
}

.warning {
    background: #fff3cd;
    border-left: 4px solid #ffc107;
    color: #856404;
}

.warning::before {
    content: '\f071';
    color: #ffc107;
}

.danger {
    background: #f8d7da;
    border-left: 4px solid #dc3545;
    color: #721c24;
}

.danger::before {
    content: '\f06a';
    color: #dc3545;
}

.info {
    background: #d1ecf1;
    border-left: 4px solid #17a2b8;
    color: #0c5460;
}

.info::before {
    content: '\f05a';
    color: #17a2b8;
}

/* 步驟列表 */
.steps {
    counter-reset: step;
    list-style: none;
    padding-left: 0;
}

.steps > li {
    position: relative;
    padding-left: 50px;
    margin-bottom: 20px;
}

.steps > li::before {
    counter-increment: step;
    content: counter(step);
    position: absolute;
    left: 0;
    top: 0;
    width: 32px;
    height: 32px;
    background: var(--primary-color);
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 14px;
}

/* 字母標示步驟（A, B, C...），用於多階層清單的外層 */
.steps-alpha {
    counter-reset: step-alpha;
    list-style: none;
    padding-left: 0;
}

.steps-alpha > li {
    position: relative;
    padding-left: 50px;
    margin-bottom: 24px;
}

.steps-alpha > li::before {
    counter-increment: step-alpha;
    content: counter(step-alpha, upper-alpha);
    position: absolute;
    left: 0;
    top: 0;
    width: 32px;
    height: 32px;
    background: var(--primary-color);
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 14px;
}

/* 數字子步驟（1, 2, 3...），用於多階層清單的內層 */
.steps-sub {
    counter-reset: step-sub;
    list-style: none;
    padding-left: 0;
    margin-top: 10px;
}

.steps-sub > li {
    position: relative;
    padding-left: 38px;
    margin-bottom: 8px;
}

.steps-sub > li::before {
    counter-increment: step-sub;
    content: counter(step-sub);
    position: absolute;
    left: 0;
    top: 1px;
    width: 24px;
    height: 24px;
    background: rgba(74, 144, 226, 0.55);
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 12px;
}

/* 鍵盤快捷鍵 */
kbd {
    background: linear-gradient(180deg, #f8f9fa, #e9ecef);
    border: 1px solid #ced4da;
    border-radius: 4px;
    padding: 2px 6px;
    font-family: 'Consolas', monospace;
    font-size: 13px;
    box-shadow: 0 1px 2px rgba(0,0,0,0.1);
}

/* ===== 右側目錄 ===== */
.toc-sidebar {
    position: fixed;
    top: var(--header-height);
    right: 0;
    width: var(--toc-width);
    height: calc(100vh - var(--header-height));
    padding: 30px 20px;
    overflow-y: auto;
    border-left: 1px solid var(--border-color);
    background: #fff;
}

.toc-title {
    font-size: 12px;
    font-weight: 700;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 15px;
}

.toc-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.toc-list li {
    margin: 0;
}

.toc-list a {
    display: block;
    padding: 6px 0;
    color: var(--text-muted);
    text-decoration: none;
    font-size: 13px;
    border-left: 2px solid transparent;
    padding-left: 12px;
    margin-left: -2px;
    transition: all 0.2s;
}

.toc-list a:hover {
    color: var(--primary-color);
}

.toc-list a.active {
    color: var(--primary-color);
    border-left-color: var(--primary-color);
}

.toc-list li.toc-h3 a {
    padding-left: 24px;
    font-size: 12px;
}

/* ===== 頁面導航 ===== */
.page-nav {
    display: flex;
    justify-content: space-between;
    margin-top: 60px;
    padding-top: 30px;
    border-top: 1px solid var(--border-color);
}

.page-nav a {
    display: flex;
    flex-direction: column;
    padding: 15px 20px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    text-decoration: none;
    color: var(--text-color);
    max-width: 45%;
    transition: all 0.2s;
}

.page-nav a:hover {
    border-color: var(--primary-color);
    box-shadow: 0 2px 8px rgba(49, 130, 246, 0.15);
}

.page-nav .nav-label {
    font-size: 12px;
    color: var(--text-muted);
    margin-bottom: 4px;
}

.page-nav .nav-title {
    font-size: 14px;
    font-weight: 600;
    color: var(--primary-color);
}

.page-nav .prev-page {
    align-items: flex-start;
}

.page-nav .next-page {
    align-items: flex-end;
    margin-left: auto;
}

.page-nav i {
    color: var(--primary-color);
    margin-bottom: 5px;
}

/* ===== 搜尋彈窗 ===== */
.search-modal {
    position: fixed;
    inset: 0;
    background: rgba(33, 37, 41, 0.55);
    display: none;
    align-items: center;
    justify-content: center;
    padding: 20px;
    z-index: 2000;
}

.search-modal.open {
    display: flex;
}

.search-modal-content {
    position: relative;
    background: #fff;
    width: 600px;
    max-width: 90%;
    max-height: 80vh;
    border-radius: 0;
    padding: 20px;
    box-shadow: 0 20px 45px rgba(0, 0, 0, 0.2);
    display: flex;
    flex-direction: column;
    animation: modalFadeIn 0.2s ease;
}

@keyframes modalFadeIn {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.search-modal-content h3 {
    margin-bottom: 18px;
    color: #2f3b4c;
}

.search-modal-header {
    margin-bottom: 15px;
}

.search-modal-header input {
    width: 100%;
    padding: 8px 10px;
    border: 1px solid #ced4da;
    border-radius: 0;
    font-size: 14px;
    transition: border-color 0.2s ease;
}

.search-modal-header input:focus {
    border-color: #4CAF50;
    outline: none;
    box-shadow: 0 0 0 3px rgba(76, 175, 80, 0.1);
}

.modal-close {
    position: absolute;
    top: 15px;
    right: 15px;
    background: none;
    border: none;
    font-size: 24px;
    color: #6c757d;
    cursor: pointer;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 4px;
    transition: all 0.2s ease;
    z-index: 10;
}

.modal-close:hover {
    background-color: #f8f9fa;
    color: #495057;
}

.modal-close:active {
    transform: scale(0.95);
}

.search-results {
    overflow-y: auto;
    flex: 1;
}

.search-result-item {
    padding: 12px 15px;
    border-radius: 6px;
    cursor: pointer;
    transition: background 0.2s;
}

.search-result-item:hover {
    background: var(--sidebar-bg);
}

.search-result-title {
    font-weight: 600;
    margin-bottom: 4px;
    color: var(--primary-color);
}

.search-result-excerpt {
    font-size: 13px;
    color: var(--text-muted);
}

.search-result-excerpt mark {
    background: var(--highlight-bg);
    padding: 0 2px;
}

.no-results {
    text-align: center;
    padding: 40px;
    color: var(--text-muted);
}

/* ===== 響應式 ===== */
@media (max-width: 1200px) {
    .toc-sidebar {
        display: none;
    }

    .content-area {
        margin-right: 0;
    }
}

@media (max-width: 768px) {
    .sidebar-toggle {
        display: block;
    }

    .site-title {
        font-size: 14px;
    }

    .search-box {
        width: 180px;
    }

    .sidebar {
        transform: translateX(-100%);
    }

    .sidebar.show {
        transform: translateX(0);
    }

    .main-content {
        margin-left: 0;
        margin-right: 0;
        padding: 30px 20px;
    }

    .toc-sidebar {
        display: none;
    }

    .content-area h1 {
        font-size: 26px;
    }

    .content-area h2 {
        font-size: 20px;
    }

    .page-nav {
        flex-direction: column;
        gap: 15px;
    }

    .page-nav a {
        max-width: 100%;
    }
}

/* ===== 列印樣式 ===== */
@media print {
    .top-header,
    .sidebar,
    .toc-sidebar,
    .page-nav {
        display: none !important;
    }

    .content-area {
        margin: 0;
        padding: 20px;
    }
}

/* ===== 回到頂部按鈕 ===== */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 44px;
    height: 44px;
    background: var(--primary-color);
    color: #fff;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    font-size: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    z-index: 1000;
}

.back-to-top:hover {
    background: var(--primary-dark);
    transform: translateY(-3px);
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}