/* ============================================================
   common.css — 全站公共样式（所有页面共享）
   ============================================================ */

/* ===== CSS 变量 ===== */
:root {
    --bg: #f7f8fa;
    --surface: #ffffff;
    --text-primary: #1a1a1a;
    --text-secondary: #6b7280;
    --text-tertiary: #9ca3af;
    --accent: #111827;
    --accent-soft: #f3f4f6;
    --accent-blue: #2563eb;
    --accent-blue-soft: #eff6ff;
    --accent-purple: #7c3aed;
    --accent-purple-soft: #f5f3ff;
    --accent-orange: #ea580c;
    --accent-orange-soft: #fff7ed;
    --border: rgba(0, 0, 0, 0.06);
    --border-light: #f0f1f3;
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.04), 0 12px 32px rgba(0, 0, 0, 0.06);
    --shadow-hover: 0 1px 3px rgba(0, 0, 0, 0.04), 0 20px 48px rgba(0, 0, 0, 0.1);
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 12px 28px rgba(0, 0, 0, 0.08);
    --radius: 18px;
    --radius-sm: 12px;
    --radius-md: 12px;
    --radius-lg: 16px;
}

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

/* ===== Base ===== */
body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    background: var(--bg);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    /* 防意外内容（如未来新增的固定宽度元素）撑出整页横向滚动条 */
    overflow-x: hidden;
}

/* ===== 移动端全局增强 ===== */
/* 媒体元素自适应容器宽度，避免溢出（canvas 不强制 height: auto，尊重页面/JS 设定的高度） */
img, video, svg, iframe { max-width: 100%; }
canvas { max-width: 100%; }

/* 去除移动端 Webkit 点击高亮，触摸反馈交由 :hover/:active 样式控制 */
* { -webkit-tap-highlight-color: transparent; }

/* touch-action: manipulation 消除双击缩放 300ms 延迟，提升按钮/链接响应 */
button, a, input, select, textarea, label { touch-action: manipulation; }

/* iOS Safari 聚焦 input 时若字号 < 16px 会自动放大页面，这里把表单基础字号提到 16px */
@media (max-width: 768px) {
    select, input[type="text"], input[type="number"], input[type="email"],
    input[type="search"], input[type="url"], input[type="tel"], textarea {
        font-size: 16px;
    }
}

/* ===== Container（页面可覆盖 max-width / padding） ===== */
.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 48px 24px 80px;
}

/* ===== Back link ===== */
.back-link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9rem;
    margin-bottom: 24px;
    transition: color 0.2s ease;
}
.back-link:hover { color: var(--text-primary); }
.back-link svg { width: 18px; height: 18px; }

/* ===== Header ===== */
header { margin-bottom: 24px; }

h1 {
    font-size: 1.9rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: 6px;
}

.subtitle {
    color: var(--text-secondary);
    font-size: 1rem;
}

/* ===== Utilities ===== */
.hidden { display: none !important; }

/* ===== Common form controls ===== */
select,
input[type="number"],
input[type="text"],
input[type="text"]:focus,
textarea {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--border);
    border-radius: 10px;
    font-size: 0.9rem;
    font-family: inherit;
    background: var(--surface);
    color: var(--text-primary);
    outline: none;
    transition: border-color 0.2s ease;
}
select:focus,
input:focus,
textarea:focus { border-color: var(--accent); }
textarea { resize: vertical; }

/* ===== Slider ===== */
.slider-row {
    display: flex;
    align-items: center;
    gap: 10px;
}
.slider-row input[type="range"] {
    flex: 1;
    height: 4px;
    -webkit-appearance: none;
    appearance: none;
    background: var(--accent-soft);
    border-radius: 2px;
    outline: none;
}
.slider-row input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: var(--accent);
    cursor: pointer;
}
.slider-row input[type="range"]::-moz-range-thumb {
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: var(--accent);
    cursor: pointer;
    border: none;
}
.slider-value {
    font-size: 0.82rem;
    font-weight: 600;
    color: var(--text-primary);
    min-width: 44px;
    text-align: right;
}

/* ===== Color row ===== */
.color-row {
    display: flex;
    gap: 8px;
    align-items: center;
}
.color-row input[type="color"] {
    width: 38px;
    height: 38px;
    border: 1px solid var(--border);
    border-radius: 10px;
    cursor: pointer;
    padding: 2px;
    background: var(--surface);
}
.color-row input[type="text"] { flex: 1; }

/* ===== Button ===== */
.btn {
    padding: 10px 16px;
    border: none;
    border-radius: 12px;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: opacity 0.2s ease, background 0.2s ease;
    font-family: inherit;
}
.btn:disabled { opacity: 0.4; cursor: not-allowed; }
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover:not(:disabled) { opacity: 0.85; }
.btn-secondary { background: var(--accent-soft); color: var(--text-primary); }
.btn-secondary:hover:not(:disabled) { background: var(--border); }

/* ===== Section title ===== */
.section-title {
    font-size: 0.82rem;
    font-weight: 600;
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.06em;
    margin-bottom: 12px;
    display: flex;
    align-items: center;
    gap: 8px;
}
.section-title .dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--accent);
}

/* ===== Section divider ===== */
.section-divider {
    border: none;
    border-top: 1px solid var(--border);
    margin: 20px 0;
}

/* ===== Checkbox row ===== */
.checkbox-row {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.88rem;
    font-weight: 500;
    cursor: pointer;
    user-select: none;
}
.checkbox-row input[type="checkbox"] {
    width: 18px;
    height: 18px;
    accent-color: var(--accent);
    cursor: pointer;
    flex-shrink: 0;
}

/* ===== Control group ===== */
.control-group { margin-bottom: 16px; }
.control-group label {
    display: block;
    font-size: 0.82rem;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 6px;
}

/* ===== Info chip ===== */
.info-chip {
    background: var(--accent-soft);
    border-radius: 8px;
    padding: 4px 12px;
    font-size: 0.78rem;
    color: var(--text-secondary);
}

/* ===== Hint ===== */
.hint {
    font-size: 0.8rem;
    color: var(--text-tertiary);
    line-height: 1.5;
}

/* ===== Error box（公共基础样式，页面可覆盖） ===== */
.error-box {
    padding: 16px 18px; border-radius: 12px;
    background: #fef2f2; color: #991b1b;
    border: 1px solid #fecaca; font-size: 0.88rem; line-height: 1.6;
    white-space: pre-wrap; word-break: break-all;
}

/* ===== Disabled sub-options ===== */
.sub-options.is-disabled {
    opacity: 0.4;
    pointer-events: none;
    filter: grayscale(0.3);
}

/* ============================================================
   深色主题（所有变量都只在 [data-theme="dark"] 下覆盖，页面默认浅色）
   ============================================================ */
:root {
    color-scheme: light;
}
[data-theme="dark"] {
    color-scheme: dark;
    --bg: #0b0d12;
    --surface: #141821;
    --text-primary: #e5e7eb;
    --text-secondary: #9aa3b2;
    --text-tertiary: #8b95a5;
    --accent: #a5b4fc;
    --accent-soft: #1f2333;
    --accent-blue: #60a5fa;
    --accent-blue-soft: #1e293b;
    --accent-purple: #c4b5fd;
    --accent-purple-soft: #2a2238;
    --accent-orange: #fb923c;
    --accent-orange-soft: #2a1c12;
    --border: rgba(255, 255, 255, 0.08);
    --border-light: rgba(255, 255, 255, 0.04);
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.4), 0 12px 32px rgba(0, 0, 0, 0.35);
    --shadow-hover: 0 1px 3px rgba(0, 0, 0, 0.5), 0 20px 48px rgba(0, 0, 0, 0.45);
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.35);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.35);
    --shadow-lg: 0 12px 28px rgba(0, 0, 0, 0.45);
}

[data-theme="dark"] img { filter: brightness(0.92) contrast(1.02); }

[data-theme="dark"] ::selection { background: #3730a3; color: #e5e7eb; }

[data-theme="dark"] .card,
[data-theme="dark"] .tool-card,
[data-theme="dark"] .code-item,
[data-theme="dark"] .swatch,
[data-theme="dark"] .history-chip,
[data-theme="dark"] .chip,
[data-theme="dark"] .text-input,
[data-theme="dark"] .textarea,
[data-theme="dark"] .picker-preview,
[data-theme="dark"] .btn,
[data-theme="dark"] .export-preview-header,
[data-theme="dark"] .canvas-box,
[data-theme="dark"] .category-tab,
[data-theme="dark"] select,
[data-theme="dark"] input[type="text"],
[data-theme="dark"] input[type="number"],
[data-theme="dark"] textarea {
    background-color: var(--surface);
}

[data-theme="dark"] .toast {
    background: rgba(229, 231, 235, 0.95);
    color: #0b0d12;
    box-shadow: 0 8px 28px rgba(0, 0, 0, 0.55);
}

/* ============================================================
   深色主题：修复各工具页面硬编码颜色（文字可读性）
   ============================================================ */

/* 错误提示框 */
[data-theme="dark"] .error-box,
[data-theme="dark"] .error-state,
[data-theme="dark"] .error-msg,
[data-theme="dark"] .error-toast {
    background: rgba(239, 68, 68, 0.12);
    color: #f87171;
    border-color: rgba(239, 68, 68, 0.25);
}
[data-theme="dark"] .error-state p { color: #f87171; }

/* 警告提示框 */
[data-theme="dark"] .warn-box,
[data-theme="dark"] .limit-tip {
    background: rgba(249, 115, 22, 0.12);
    color: #fb923c;
    border-color: rgba(249, 115, 22, 0.25);
}
[data-theme="dark"] .limit-tip strong { color: #fdba74; }

/* 成功 / 警告 徽章 */
[data-theme="dark"] .badge.yes,
[data-theme="dark"] .format-badge.supported {
    background: rgba(34, 197, 94, 0.12);
    color: #4ade80;
    border-color: rgba(34, 197, 94, 0.25);
}
[data-theme="dark"] .badge.no,
[data-theme="dark"] .format-badge.unsupported {
    background: rgba(249, 115, 22, 0.12);
    color: #fb923c;
    border-color: rgba(249, 115, 22, 0.25);
}

/* 压缩率标签 */
[data-theme="dark"] .save-rate {
    background: rgba(34, 197, 94, 0.12);
    color: #4ade80;
}
[data-theme="dark"] .save-rate.increased {
    background: rgba(239, 68, 68, 0.12);
    color: #f87171;
}

/* PDF 压缩预览面板白色背景 */
[data-theme="dark"] .preview-badge,
[data-theme="dark"] .preview-item {
    background: var(--accent-soft);
}
[data-theme="dark"] .preview-badge.ready {
    color: #4ade80;
    background: rgba(34, 197, 94, 0.12);
}
[data-theme="dark"] .preview-badge.calc {
    color: #60a5fa;
    background: rgba(37, 99, 235, 0.12);
}
[data-theme="dark"] .preview-value-comp { color: #60a5fa; }
[data-theme="dark"] .preview-value-ratio { color: #4ade80; }
[data-theme="dark"] .preview-value-ratio.bad { color: #f87171; }

/* 3D 模型预览器浮层按钮 */
[data-theme="dark"] .viewer-btn {
    background: rgba(20, 24, 33, 0.9);
    color: var(--text-primary);
}
[data-theme="dark"] .viewer-btn:hover { background: rgba(30, 35, 48, 0.95); }
[data-theme="dark"] .viewer-stats {
    background: rgba(20, 24, 33, 0.9);
    color: var(--text-secondary);
}
[data-theme="dark"] .viewer-stats strong { color: var(--text-primary); }
[data-theme="dark"] .loading-overlay { background: rgba(11, 13, 18, 0.7); }

/* 思维导图画布 & 编辑框 */
[data-theme="dark"] .canvas-wrap {
    background: #0f1219;
    background-image: radial-gradient(circle, rgba(255, 255, 255, 0.06) 1px, transparent 1px);
    background-size: 24px 24px;
}
[data-theme="dark"] .node-text-edit {
    background: var(--surface);
    color: var(--text-primary);
}
[data-theme="dark"] .hint-bar {
    background: rgba(20, 24, 33, 0.9);
    color: var(--text-secondary);
}

/* 危险操作按钮 */
[data-theme="dark"] .tool-btn.danger,
[data-theme="dark"] .ctx-item.danger { color: #f87171; border-color: rgba(239, 68, 68, 0.25); }
[data-theme="dark"] .tool-btn.danger:hover,
[data-theme="dark"] .ctx-item.danger:hover { background: rgba(239, 68, 68, 0.12); }

/* 图片滤镜替换按钮 */
[data-theme="dark"] .replace-btn {
    background: rgba(20, 24, 33, 0.92);
    color: var(--text-secondary);
}
[data-theme="dark"] .replace-btn:hover {
    background: var(--surface);
    color: var(--text-primary);
}

/* 取色器色值标注 */
[data-theme="dark"] .swatch-caption {
    background: rgba(20, 24, 33, 0.92);
    color: var(--text-primary);
}

/* 桌面便签删除按钮 hover */
[data-theme="dark"] .note-remove:hover {
    background: rgba(239, 68, 68, 0.15);
    color: #f87171;
    border-color: rgba(239, 68, 68, 0.3);
}

/* 下拉框箭头颜色（水印/视频水印/图片滤镜页面） */
[data-theme="dark"] .font-select-wrap select,
[data-theme="dark"] .form-group select {
    background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%239aa3b2' stroke-width='2.2' stroke-linecap='round' stroke-linejoin='round'><polyline points='6 9 12 15 18 9'/></svg>");
}

/* 浅色 hover 背景修复（避免浅色 bg + 浅色文字） */
[data-theme="dark"] .format-chip:hover { background: var(--accent-soft); color: var(--text-primary); }
[data-theme="dark"] .btn-secondary:hover { background: var(--accent-soft); }

/* 思维导图导出弹窗：滑块与确认按钮（近黑色在深色背景上看不清） */
[data-theme="dark"] .size-row input[type="range"] { accent-color: #60a5fa; }
[data-theme="dark"] .modal-actions #imgSizeConfirm {
    background: #2563eb; color: #fff; border-color: #2563eb;
}

/* ============================================================
   固定侧边栏 + has-sidebar 布局
   ============================================================ */
body.has-sidebar {
    padding-left: 0;
}
@media (min-width: 1081px) {
    body.has-sidebar {
        padding-left: 260px;
    }
}

/* 侧边栏容器 */
.sidebar {
    position: fixed;
    top: 0;
    left: 0;
    width: 260px;
    height: 100vh;
    background: var(--surface);
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    z-index: 60;
    box-shadow: 2px 0 24px rgba(0, 0, 0, 0.03);
    transform: translateX(0);
    transition: transform 0.28s cubic-bezier(.2,.9,.3,1);
}
[data-theme="dark"] .sidebar {
    box-shadow: 2px 0 24px rgba(0, 0, 0, 0.35);
    background: #0f1219;
}
/* 移动端默认收起 */
@media (max-width: 1080px) {
    .sidebar {
        transform: translateX(-100%);
        width: min(300px, 86vw);
    }
    .sidebar.show { transform: translateX(0); }
    .sidebar-backdrop {
        position: fixed; inset: 0;
        background: rgba(15, 18, 25, 0.45);
        backdrop-filter: blur(2px);
        z-index: 55;
        opacity: 0; pointer-events: none;
        transition: opacity 0.25s ease;
    }
    .sidebar-backdrop.show { opacity: 1; pointer-events: auto; }
    body.sidebar-locked { overflow: hidden; }
}

/* 侧边栏头部 */
.sidebar-header {
    display: flex; align-items: center; justify-content: space-between;
    padding: 18px 18px 14px;
    border-bottom: 1px solid var(--border);
}
.sidebar-brand {
    display: flex; align-items: center; gap: 10px;
    text-decoration: none; color: inherit;
}
.sidebar-logo {
    width: 36px; height: 36px; border-radius: 10px;
    background: var(--accent);
    color: #fff;
    display: inline-flex; align-items: center; justify-content: center;
    font-weight: 700; font-size: 1.05rem;
    flex-shrink: 0;
    box-shadow: 0 4px 10px rgba(99, 102, 241, 0.35);
}
.sidebar-brand-title {
    font-weight: 700; font-size: 0.95rem; letter-spacing: -0.01em;
    white-space: nowrap;
}
.sidebar-close {
    width: 32px; height: 32px; border-radius: 8px;
    background: transparent; border: 1px solid transparent;
    color: var(--text-secondary);
    cursor: pointer;
    display: inline-flex; align-items: center; justify-content: center;
    transition: all 0.18s ease;
}
.sidebar-close:hover {
    color: var(--text-primary);
    background: var(--accent-soft);
    border-color: var(--border);
}
.sidebar-close svg { width: 16px; height: 16px; }
@media (min-width: 1081px) { .sidebar-close { display: none; } }

/* 收起侧边栏按钮（桌面端显示，移动端隐藏） */
.sidebar-collapse {
    width: 32px; height: 32px; border-radius: 8px;
    background: transparent; border: 1px solid transparent;
    color: var(--text-secondary);
    cursor: pointer;
    display: inline-flex; align-items: center; justify-content: center;
    transition: all 0.18s ease;
}
.sidebar-collapse:hover {
    color: var(--text-primary);
    background: var(--accent-soft);
    border-color: var(--border);
}
.sidebar-collapse svg { width: 16px; height: 16px; }
@media (max-width: 1080px) { .sidebar-collapse { display: none; } }

/* 桌面端侧边栏收起：侧边栏滑出，内容占满整行 */
body.sidebar-collapsed { padding-left: 0 !important; }
body.sidebar-collapsed .sidebar { transform: translateX(-100%); }

/* 桌面端收起后，显示左上角展开按钮（更明显、符合点左边展开的直觉） */
@media (min-width: 1081px) {
    body.sidebar-collapsed .sidebar-open {
        display: inline-flex;
        top: 14px;
        left: 14px;   /* 移到左上角（侧边栏原位置） */
        right: auto;
        background: var(--accent);
        color: #fff;
        border-color: var(--accent);
        box-shadow: 0 6px 20px rgba(0, 0, 0, 0.22);
    }
    body.sidebar-collapsed .sidebar-open:hover {
        background: var(--accent);
        opacity: 0.88;
        box-shadow: 0 8px 24px rgba(0, 0, 0, 0.28);
    }
}

/* 侧边栏顶部工具区（主题切换 + 搜索） */
.sidebar-tools {
    padding: 12px 14px 8px;
    display: flex; flex-direction: column; gap: 10px;
    border-bottom: 1px solid var(--border);
}
.theme-toggle {
    width: 100%;
    display: inline-flex; align-items: center; justify-content: flex-start; gap: 10px;
    padding: 10px 12px;
    border-radius: 10px;
    background: var(--accent-soft);
    border: 1px solid var(--border);
    color: var(--text-primary);
    cursor: pointer;
    font-family: inherit;
    font-size: 0.86rem; font-weight: 600;
    text-align: left;
    transition: all 0.18s ease;
    position: relative;
}
.theme-toggle:hover {
    border-color: rgba(99, 102, 241, 0.45);
    transform: translateY(-1px);
}
.theme-toggle .theme-icon {
    width: 16px; height: 16px;
    display: inline-flex; align-items: center; justify-content: center;
    transition: transform 0.3s ease, opacity 0.2s ease;
}
.theme-toggle .theme-icon svg { width: 16px; height: 16px; }
.theme-toggle .theme-icon.sun   { opacity: 1; transform: rotate(0); margin-left: 2px; }
.theme-toggle .theme-icon.moon  { position: absolute; left: 14px; opacity: 0; transform: rotate(-25deg); }
.theme-toggle[data-now="dark"] .theme-icon.sun   { opacity: 0; transform: rotate(25deg); }
.theme-toggle[data-now="dark"] .theme-icon.moon  { opacity: 1; transform: rotate(0); }
.theme-toggle .theme-label {
    text-align: left;
    line-height: 1.4;
}
.theme-toggle[data-now="dark"] .theme-label::before { content: '当前：深色模式'; display: block; }
.theme-toggle:not([data-now="dark"]) .theme-label::before { content: '当前：浅色模式'; display: block; }

/* 搜索框 */
.nav-search {
    position: relative;
}
.nav-search-icon {
    position: absolute;
    left: 11px; top: 50%; transform: translateY(-50%);
    color: var(--text-tertiary);
    display: inline-flex; align-items: center; justify-content: center;
    pointer-events: none;
}
.nav-search-icon svg { width: 15px; height: 15px; }
.nav-search input {
    width: 100%;
    padding: 10px 12px 10px 34px;
    border-radius: 10px;
    border: 1px solid var(--border);
    background: var(--bg);
    color: var(--text-primary);
    font-family: inherit;
    font-size: 0.84rem;
    outline: none;
    transition: border-color 0.18s ease, background 0.18s ease;
}
.nav-search input::placeholder { color: var(--text-tertiary); }
.nav-search input:focus { border-color: var(--accent); background: var(--surface); }

/* 导航分组 */
.sidebar > .nav-section {
    padding: 8px 10px;
}
.nav-category {
    padding: 10px 10px 6px;
    font-size: 0.7rem;
    font-weight: 700;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--text-tertiary);
}
.nav-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 9px 12px;
    border-radius: 10px;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.88rem;
    font-weight: 500;
    margin-bottom: 2px;
    position: relative;
    transition: all 0.16s ease;
    white-space: nowrap;
}
.nav-item:hover {
    color: var(--text-primary);
    background: var(--accent-soft);
}
.nav-item.active {
    color: var(--text-primary);
    background: var(--accent-soft);
    box-shadow: inset 2px 0 0 var(--accent);
    font-weight: 600;
}
.nav-icon {
    width: 18px; height: 18px; flex-shrink: 0;
    display: inline-flex; align-items: center; justify-content: center;
    color: inherit;
    opacity: 0.88;
}
.nav-icon svg { width: 18px; height: 18px; }
.nav-name { overflow: hidden; text-overflow: ellipsis; }
.nav-active-dot {
    width: 6px; height: 6px; border-radius: 50%;
    background: var(--accent);
    margin-left: auto;
    box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 18%, transparent);
}
@supports not (color-mix(in srgb, red 10%, white)) {
    .nav-active-dot { box-shadow: 0 0 0 3px rgba(99,102,241,0.18); }
}

/* 可滚动 */
.sidebar { overflow-y: auto; }
.sidebar::-webkit-scrollbar { width: 6px; }
.sidebar::-webkit-scrollbar-thumb { background: transparent; border-radius: 3px; }
.sidebar:hover::-webkit-scrollbar-thumb { background: var(--border); }

/* 底部版权 */
.sidebar-foot {
    margin-top: auto;
    padding: 16px 18px 22px;
    font-size: 0.72rem;
    color: var(--text-tertiary);
    letter-spacing: 0.02em;
    border-top: 1px solid var(--border);
}

/* 顶栏汉堡按钮（移动端，固定右上角，避免内容被挡住） */
.sidebar-open {
    position: fixed;
    top: 14px;
    right: 14px;
    z-index: 50;
    width: 40px; height: 40px;
    border-radius: 12px;
    background: var(--surface);
    color: var(--text-primary);
    border: 1px solid var(--border);
    box-shadow: var(--shadow-sm);
    cursor: pointer;
    display: none;
    align-items: center; justify-content: center;
    transition: all 0.18s ease;
}
.sidebar-open svg { width: 18px; height: 18px; }
.sidebar-open:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}
@media (max-width: 1080px) {
    .sidebar-open { display: inline-flex; }
    /* 给移动端页面容器预留汉堡按钮的空间，避免首屏标题被遮挡 */
    .has-sidebar .container { padding-top: 68px; }
}

/* 对首页大标题做额外顶部对齐（因为原首页 container padding: 80px 24px 120px 已经够大） */
@media (max-width: 1080px) {
    .has-sidebar header { margin-top: 8px; }
}

/* ============================================================
   分享按钮 + 二维码分享面板
   ============================================================ */
.share-fab {
    position: fixed;
    right: 20px;
    bottom: 24px;
    z-index: 90;
    width: 48px; height: 48px;
    border-radius: 50%;
    background: var(--accent);
    color: #fff;
    border: none;
    cursor: pointer;
    display: inline-flex;
    align-items: center; justify-content: center;
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.2);
    transition: transform 0.18s ease, box-shadow 0.18s ease;
}
.share-fab:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 28px rgba(0, 0, 0, 0.28);
}
.share-fab svg { width: 22px; height: 22px; }

.share-modal {
    position: fixed;
    inset: 0;
    z-index: 300;
    display: none;
}
.share-modal.show { display: block; }
.share-backdrop {
    position: absolute;
    inset: 0;
    background: rgba(15, 18, 25, 0.5);
    backdrop-filter: blur(2px);
}
.share-dialog {
    position: absolute;
    top: 50%; left: 50%;
    transform: translate(-50%, -50%);
    width: min(340px, 90vw);
    background: var(--surface);
    border-radius: 18px;
    box-shadow: 0 24px 64px rgba(0, 0, 0, 0.25);
    overflow: hidden;
}
.share-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 20px;
    border-bottom: 1px solid var(--border);
    font-weight: 600;
    font-size: 0.95rem;
    color: var(--text-primary);
}
.share-close {
    width: 28px; height: 28px;
    border-radius: 8px;
    border: none;
    background: transparent;
    color: var(--text-secondary);
    cursor: pointer;
    display: inline-flex;
    align-items: center; justify-content: center;
    transition: all 0.18s ease;
}
.share-close:hover { background: var(--accent-soft); color: var(--text-primary); }
.share-close svg { width: 16px; height: 16px; }

.share-body {
    padding: 24px 20px 20px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 14px;
}
.share-qr {
    width: 200px; height: 200px;
    display: flex;
    align-items: center; justify-content: center;
    border-radius: 12px;
    /* 二维码必须白底，深色模式也保持，否则手机扫不出 */
    background: #ffffff;
    padding: 8px;
    box-shadow: 0 4px 14px rgba(0, 0, 0, 0.08);
}
.share-qr canvas { width: 184px; height: 184px; }
.share-qr-error { color: var(--text-secondary); font-size: 0.85rem; }
.share-url {
    max-width: 100%;
    font-size: 0.78rem;
    color: var(--text-tertiary);
    word-break: break-all;
    text-align: center;
    line-height: 1.5;
}
.share-actions { width: 100%; }
.share-copy-btn {
    width: 100%;
    padding: 11px 16px;
    border: none;
    border-radius: 12px;
    background: var(--accent);
    color: #fff;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    font-family: inherit;
    transition: opacity 0.18s ease;
}
.share-copy-btn:hover { opacity: 0.88; }
.share-copy-btn.copied { background: #16a34a; }
.share-copy-btn.failed { background: #dc2626; }
.share-hint {
    font-size: 0.75rem;
    color: var(--text-tertiary);
}