:root {
    /* 源力设计系统令牌（与 header.css / yuanli.css 对齐，避免外壳视觉不统一） */
    --sidebar-bg: #ffffff;
    --sidebar-hover: #F1F3F5;        /* bg-5 hover 底（规范） */
    --sidebar-nav-hover: rgba(22, 100, 255, 0.08);  /* state-hover 蓝色微底（规范 sidenav hover） */
    --sidebar-active: #1664ff;       /* primary */
    --sidebar-active-bg: #f3f7ff;    /* primary-container */
    --sidebar-submenu-active-bg: #f0f0f0;  /* 二级菜单选中背景（截图灰底圆角） */
    --sidebar-text: #42464e;         /* text-2 */
    --sidebar-text-strong: #0c0d0e;  /* text-1 */
    --sidebar-icon: #737a87;         /* text-3 */
    --sidebar-accent: #1664ff;       /* primary */
    --sidebar-border: #eaedf1;       /* border-1 */
    --sidebar-width: 240px;
    --sidebar-collapsed-width: 80px;
    --transition-speed: 0.3s;
    --header-height: 58px;           /* 与 header.css 统一，消除顶栏/侧栏错位 */
    --footer-height: 80px;
    --content-bg: #f8f9fa;   /* 内容区统一背景：与 css/style.css 的 body 背景对齐，消除 task/stu 页面背景差异 */
}

/* 侧边栏基础样式 */
#sidebar,
.admin-sidebar {
    background: var(--sidebar-bg);
    color: var(--sidebar-text);
    /* 自有字体栈，避免 task/users 页未加载全局 body 字体时侧边栏文字退化为浏览器默认 */
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
    font-size: 13px;
    /* 显式指定行高，避免依赖 body 继承（Bootstrap / 各页内联样式可能覆写 body line-height，导致侧栏高度不一致） */
    line-height: 1.5;
    position: fixed;
    top: var(--header-height);
    left: 0;
    width: var(--sidebar-width);
    height: calc(100vh - var(--header-height));
    transition: width var(--transition-speed) ease, transform var(--transition-speed) ease;
    z-index: 1020;
    overflow-y: auto;
    overflow-x: hidden;
    display: flex;
    flex-direction: column;
}

/* 侧边栏折叠状态 */
#sidebar.collapsed {
    width: var(--sidebar-collapsed-width);
}

/* 主内容区样式 - 与侧边栏同步过渡 */
#main-content {
    flex: 1;
    margin-left: var(--sidebar-width);
    margin-top: var(--header-height);
    padding: 10px 20px 20px 20px;
    min-height: calc(100vh - var(--header-height));
    transition: margin-left var(--transition-speed) ease !important;
    position: relative;
    width: calc(100% - var(--sidebar-width));
    background-color: var(--content-bg);
}

/* 源力设计系统作用域（task / users / main）：内容区背景统一为白色，
   与设计规范 --bg-page:#FFFFFF 对齐；特异性 (1,1,0) 压过上方 #main-content 的 (1,0,0)。 */
#main-content.yl-app {
    background-color: #ffffff;
}

#main-content.expanded {
    margin-left: var(--sidebar-collapsed-width) !important;
    width: calc(100% - var(--sidebar-collapsed-width));
}

#sidebar ~ #main-content {
    transition: margin-left var(--transition-speed) ease !important;
}

#sidebar.collapsed ~ #main-content {
    margin-left: var(--sidebar-collapsed-width) !important;
    width: calc(100% - var(--sidebar-collapsed-width));
}

/* 确保在移动端正确处理 */
@media (max-width: 992px) {
    #sidebar ~ #main-content,
    #sidebar.collapsed ~ #main-content {
        margin-left: 0 !important;
        width: 100% !important;
    }
    
    #main-content {
        margin-left: 0 !important;
        width: 100% !important;
        padding: 10px 15px 15px 15px;
        margin-top: var(--header-height) !important;
        min-height: calc(100vh - var(--header-height));
    }
    
    #main-content.expanded {
        margin-left: 0 !important;
        width: 100% !important;
    }
    
    body {
        overflow-x: hidden;
    }
}

#sidebar.collapsed .sidebar-header h3,
#sidebar.collapsed .menu-text {
    display: none;
}
/* 折叠状态：footer 只保留版本号胶囊 */
#sidebar.collapsed .sidebar-footer .sf-brand,
#sidebar.collapsed .sidebar-footer .sf-sep,
#sidebar.collapsed .sidebar-footer .sf-c {
    display: none;
}
#sidebar.collapsed .sidebar-footer {
    padding: 10px 0 12px;
}
#sidebar.collapsed .sidebar-footer .sf-inner {
    justify-content: center;
}

#sidebar.collapsed .sidebar-toggle i {
    transform: rotate(180deg);
}

/* 侧边栏头部 */
.sidebar-header {
    padding: 20px 16px;
    border-bottom: 1px solid var(--sidebar-border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-shrink: 0;
}

.sidebar-header h3 {
    font-size: 1.25rem;
    font-weight: 500;
    margin: 0;
    color: var(--sidebar-text);
    transition: opacity var(--transition-speed);
}

/* 侧边栏切换按钮 */
.sidebar-toggle {
    background: var(--sidebar-hover);
    border-radius: 50%;
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
}

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

.sidebar-toggle i {
    color: var(--sidebar-text);
    transition: transform var(--transition-speed);
}

/* 侧边栏滚动条美化（Firefox） */
#sidebar,
.admin-sidebar,
#menuContainer,
.components {
    scrollbar-width: thin;
    scrollbar-color: #d1d5da transparent;
    transition: scrollbar-color 0.2s ease;
}
#sidebar:hover,
.admin-sidebar:hover,
#menuContainer:hover,
.components:hover {
    scrollbar-color: #b8bcc4 transparent;
}

/* 侧边栏滚动条美化（Webkit：Chrome/Safari/Edge） */
#sidebar::-webkit-scrollbar,
.admin-sidebar::-webkit-scrollbar,
#menuContainer::-webkit-scrollbar,
.components::-webkit-scrollbar {
    width: 6px;
    height: 6px;
}
#sidebar::-webkit-scrollbar-track,
.admin-sidebar::-webkit-scrollbar-track,
#menuContainer::-webkit-scrollbar-track,
.components::-webkit-scrollbar-track {
    background: transparent;
}
#sidebar::-webkit-scrollbar-thumb,
.admin-sidebar::-webkit-scrollbar-thumb,
#menuContainer::-webkit-scrollbar-thumb,
.components::-webkit-scrollbar-thumb {
    background: #d1d5da;
    border-radius: 3px;
    transition: background 0.2s ease;
}
#sidebar::-webkit-scrollbar-thumb:hover,
.admin-sidebar::-webkit-scrollbar-thumb:hover,
#menuContainer::-webkit-scrollbar-thumb:hover,
.components::-webkit-scrollbar-thumb:hover {
    background: #959da5;
}
#sidebar::-webkit-scrollbar-thumb:active,
.admin-sidebar::-webkit-scrollbar-thumb:active,
#menuContainer::-webkit-scrollbar-thumb:active,
.components::-webkit-scrollbar-thumb:active {
    background: #6b7280;
}

/* 菜单容器样式 */
#menuContainer,
.components {
    padding: 16px 0;
    flex: 1;
    overflow-y: auto;
    overflow-x: hidden;
}

/* 菜单项样式 */
.admin-sidebar .nav-item {
    position: relative;
    margin: 4px 12px;
    border-radius: 6px;
    overflow: hidden;
}

.has-submenu {
    margin-bottom: 0 !important;
}

/* 导航链接样式 */
.admin-sidebar .nav-link {
    color: var(--sidebar-text);
    display: flex;
    align-items: center;
    padding: 12px 16px;
    text-decoration: none;
    transition: all 0.2s ease;
    position: relative;
    border-radius: 6px;
    /* — 高度防御：防止全局 .nav-link / 其它模块 CSS 污染导致跨页面高度不一致 — */
    min-height: 44px;       /* 与 task.php 页默认渲染尺寸对齐：padding12*2 + content~20 */
    height: auto;           /* 不锁死 height，子菜单展开时父级保持一致 */
    box-sizing: border-box;
    line-height: 1.5;       /* 显式声明行高，避免 body line-height 继承差异 */
}

.admin-sidebar .nav-link:hover {
    background: var(--sidebar-nav-hover);
    color: var(--sidebar-active);
}

/* 一级菜单激活态：仅改变文字/图标颜色，无背景（与截图一致） */
.admin-sidebar .nav-link.active {
    background: transparent;
    color: var(--sidebar-active);
    font-weight: 500;
}

/* 移除左侧主色指示条，避免与截图简洁风格冲突 */
.admin-sidebar .nav-link.active::before {
    display: none;
}

/* 导航图标样式（保留低特异性，让 hover/active 颜色能正确覆盖） */
.admin-sidebar .nav-link i {
    font-size: 1.2rem;
    width: 24px;
    text-align: center;
    margin-right: 12px;
    color: var(--sidebar-icon);
    transition: margin var(--transition-speed);
}

/* Lucide 基础图标：菜单图标渲染为 <svg class="lucide"> 后与 bi 同尺寸/同色/同缩进 */
.admin-sidebar .nav-link svg.lucide {
    width: 1.2rem;
    height: 1.2rem;
    flex-shrink: 0;
    margin-right: 12px;
    color: var(--sidebar-icon);
    transition: margin var(--transition-speed);
}
.admin-sidebar .nav-link.active svg.lucide {
    color: var(--sidebar-active);
}

/* — 一级菜单首个图标尺寸防御：跨页面统一高度，不依赖行高渲染差异 —
   根因：不同模块页面的全局 CSS 会让 i 元素 display/line-height 渲染不一致：
     - task.php: icon 实际渲染高度 = font-size(19.2px)
     -  stu.php: icon 实际渲染高度 = line-height(28.8px)
   下面规则显式锁定首个功能图标（非折叠箭头）的盒模型，保证两页一致。
   不放在上方 .admin-sidebar .nav-link i 中以避免影响 hover/active 颜色继承。 */
.admin-sidebar .components > .nav-item > .nav-link > i:first-child:not(.collapse-control),
.admin-sidebar .components > .nav-item > .nav-link > svg:first-child.lucide:not(.collapse-control) {
    line-height: 1;
    height: 1.2rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.admin-sidebar .nav-link > i:first-child {
    flex-shrink: 0;
    color: inherit !important;
}

.admin-sidebar .nav-link:hover i,
.admin-sidebar .nav-link.active i {
    color: var(--sidebar-active);
}

#sidebar.collapsed .nav-link i {
    margin-right: 0;
}

.admin-sidebar.collapsed .has-submenu > .nav-link > i:first-child {
    margin-right: 0;
}

/* 菜单文本 */
.menu-text {
    flex-grow: 1;
    transition: opacity var(--transition-speed);
}

.admin-sidebar .nav-link:hover .menu-text,
.admin-sidebar .nav-link.active .menu-text {
    color: var(--sidebar-active);
}

/* 折叠控制 */
.collapse-control {
    font-size: 0.8rem !important;
    display: inline-block !important;
    transition: transform 0.3s ease;
}

.nav-link[aria-expanded="true"] > .collapse-control {
    transform: rotate(180deg);
}

#sidebar.collapsed .collapse-control,
.admin-sidebar.collapsed .has-submenu > .nav-link > .collapse-control {
    display: none !important;
}

/* 子菜单样式 —— 简洁化：不显示图标，仅用缩进区分层级 */
.submenu {
    background: transparent;
    border-radius: 0 0 6px 6px;
    margin-top: 0;
    padding: 4px 0 8px 12px;
    min-height: 60px;
}

.submenu.collapse {
    transition: height 0.3s ease;
}

.submenu.collapse.show {
    height: auto;
}

.submenu .list-unstyled {
    max-height: none;
    overflow-y: visible;
    width: 100%;
}

/* 子菜单链接样式：纯文字、左缩进与父级文字对齐 */
.submenu .nav-link {
    padding: 9px 12px 9px 28px;
    font-size: 13px;
    height: auto;
    min-height: 40px;
    border-radius: 8px;
    color: var(--sidebar-text);
}

.submenu .nav-link:hover {
    background: var(--sidebar-hover);
    color: var(--sidebar-active);
}

/* 二级菜单高亮样式：灰色圆角背景 + 蓝色文字（与截图一致） */
.submenu .nav-link.active {
    background: var(--sidebar-submenu-active-bg);
    color: var(--sidebar-active);
    font-weight: 500;
}

.submenu .nav-item {
    margin: 2px 8px 2px 0;
    width: calc(100% - 8px);
}

/* 子菜单展开 */
.has-submenu > .nav-link {
    position: relative;
}

/* 子菜单与父级之间无需分隔线，保持截图中的连续感 */
.has-submenu > .nav-link + .submenu {
    position: relative;
    z-index: 1;
    border-top: none;
}

/* 侧边栏底部：品牌 + 版本 + 年份，紧凑居中 */
.sidebar-footer {
    padding: 12px 16px 14px;
    border-top: 1px solid var(--sidebar-border);
    display: flex;
    justify-content: center;
    flex-shrink: 0;
}
.sidebar-footer .sf-inner {
    display: flex;
    align-items: center;
    gap: 4px;
    font-size: 11px;
    line-height: 1;
    color: var(--sidebar-icon, rgba(255,255,255,.45));
    letter-spacing: .2px;
    white-space: nowrap;
}
.sidebar-footer .sf-brand i {
    margin-right: 3px;
    font-size: 12px;
    color: var(--sidebar-accent, #ffd27a);
    vertical-align: -1px;
}
.sidebar-footer .sf-ver {
    font-variant-numeric: tabular-nums;
    font-size: 10px;
    padding: 1px 5px;
    border-radius: 3px;
    background: rgba(255,255,255,.08);
    color: var(--sidebar-icon, rgba(255,255,255,.55));
}
.sidebar-footer .sf-sep {
    opacity: .5;
    font-size: 10px;
}
.sidebar-footer .sf-c {
    opacity: .7;
}

/* 折叠按钮样式 */
.sidebar-collapse-btn {
    display: flex;
    align-items: center;
    cursor: pointer;
    color: var(--sidebar-icon);
    transition: all 0.2s ease;
    padding: 8px 16px;
    border-radius: 4px;
    border: 1px solid var(--sidebar-border);
    background: transparent;
}

.sidebar-collapse-btn:hover {
    color: var(--sidebar-text);
    background: var(--sidebar-hover);
}

.sidebar-collapse-btn i {
    margin-right: 8px;
    font-size: 0.9rem;
}

/* 折叠子菜单隐藏 */
.admin-sidebar.collapsed .submenu,
.admin-sidebar.collapsed .submenu * {
    display: none !important;
}

/* 管理员侧边栏补充样式 */
.admin-sidebar .nav-link.active > i:first-child,
.admin-sidebar .nav-link.active:hover > i:first-child,
.admin-sidebar .submenu .nav-link.active > i:first-child {
    color: var(--sidebar-active) !important;
}

/* 键盘可达性：源力蓝色聚焦环（替代裸 outline:none，符合 DESIGN.md §7 Do's#4） */
.admin-sidebar .nav-link:focus-visible,
.sidebar-collapse-btn:focus-visible,
.sidebar-toggle:focus-visible,
.mobile-toggle:focus-visible {
    outline: 2px solid rgba(22, 100, 255, 0.6);
    outline-offset: 2px;
}

/* 移动端菜单按钮 */
.mobile-toggle {
    display: none;
    position: fixed;
    top: 12px;
    left: 12px;
    z-index: 99;
    background: var(--sidebar-bg);
    color: var(--sidebar-text);
    border: 1px solid var(--sidebar-border);
    border-radius: 4px;
    padding: 8px 12px;
    font-size: 1.2rem;
    cursor: pointer;
    transition: all 0.2s ease;
}

.mobile-toggle:hover {
    background: var(--sidebar-hover);
}

/* 移动端遮罩层 */
#sidebar-overlay {
    position: fixed;
    top: var(--header-height, 58px);
    left: 0;
    width: 100%;
    height: calc(100vh - var(--header-height, 58px));
    background: rgba(12, 13, 14, 0.45);
    z-index: 1038;
    display: none;
    backdrop-filter: blur(2px);
    transition: opacity 0.3s;
}

#sidebar-overlay.show {
    display: block;
}

/* 响应式设计 */
@media (max-width: 992px) {
    #sidebar,
    .admin-sidebar {
        transform: translateX(-100%);
        width: 280px;
        max-width: 280px;
        overflow: hidden;
        top: var(--header-height, 58px);
        left: 0;
        height: calc(100vh - var(--header-height, 58px));
        position: fixed;
        z-index: 1040;
        transition: transform 0.3s ease;
        box-shadow: none;
        background: var(--sidebar-bg);
    }
    
    #sidebar.show,
    .admin-sidebar.show {
        transform: translateX(0);
        overflow-y: auto;
        box-shadow: 0 8px 24px rgba(12, 13, 14, 0.12);
    }
    
    .mobile-toggle {
        display: block;
    }
    
    .sidebar-header {
        display: flex;
        padding: 16px;
    }
    
    #menuContainer,
    .components {
        padding: 12px 0;
    }
    
    .nav-item {
        margin: 4px 12px;
    }
    
    .nav-link {
        padding: 12px 12px;
        font-size: 0.95rem;
    }
    
    .nav-link i {
        font-size: 1.1rem;
        margin-right: 12px;
    }
    
    .submenu {
        padding: 4px 0 8px 8px;
    }
    
    .submenu .nav-link {
        padding: 10px 12px 10px 28px;
        font-size: 13px;
        min-height: 40px;
        border-radius: 8px;
    }
    
    .sidebar-footer {
        padding: 12px;
    }
    
    .sidebar-collapse-btn {
        padding: 8px 12px;
    }
}

@media (max-width: 768px) {
    /* 移动端顶栏高度为 48px（见 header.css），侧栏/遮罩须同步，避免错位留出空隙 */
    :root {
        --header-height: 48px;
    }

    #sidebar,
    .admin-sidebar {
        width: 260px;
        max-width: 260px;
    }
    
    #sidebar.show,
    .admin-sidebar.show {
        width: 260px;
        max-width: 260px;
    }
    
    .mobile-toggle {
        top: 8px;
        left: 8px;
        padding: 6px 12px;
        font-size: 1rem;
    }
    
    .sidebar-header h3 {
        font-size: 1.15rem;
    }
    
    .nav-link {
        padding: 12px 12px;
        font-size: 0.92rem;
    }
    
    .nav-link i {
        font-size: 1.05rem;
        margin-right: 8px;
    }
    
    .submenu .nav-link {
        padding: 8px 12px 8px 28px;
        font-size: 0.88rem;
        border-radius: 8px;
    }
    
    .submenu .nav-link i {
        font-size: 0.85rem;
        margin-right: 8px;
    }
    
    .collapse-control {
        font-size: 0.75rem !important;
    }
}

@media (max-width: 576px) {
    #sidebar,
    .admin-sidebar {
        width: 240px;
        max-width: 240px;
    }
    
    #sidebar.show,
    .admin-sidebar.show {
        width: 240px;
        max-width: 240px;
    }
    
    .mobile-toggle {
        top: 8px;
        left: 8px;
        padding: 5px 8px;
        font-size: 0.95rem;
    }
    
    .sidebar-header {
        padding: 12px 16px;
    }
    
    .sidebar-header h3 {
        font-size: 1rem;
    }
    
    #menuContainer,
    .components {
        padding: 8px 0;
    }
    
    .nav-item {
        margin: 4px 8px;
    }
    
    .nav-link {
        padding: 12px 12px;
        font-size: 0.9rem;
    }
    
    .nav-link i {
        font-size: 1rem;
        width: 22px;
        margin-right: 8px;
    }
    
    .menu-text {
        font-size: 0.9rem;
    }
    
    .submenu {
        padding: 4px 0 8px 8px;
    }
    
    .submenu .nav-link {
        padding: 8px 12px 8px 28px;
        font-size: 0.86rem;
        min-height: 40px;
        border-radius: 8px;
    }
    
    .submenu .nav-link i {
        font-size: 0.8rem;
        margin-right: 8px;
    }
    
    .submenu .nav-item {
        margin: 6px 0;
        width: calc(100% - 6px);
    }
    
    .sidebar-footer {
        padding: 12px 12px;
    }
    
    .sidebar-collapse-btn {
        padding: 8px 12px;
        font-size: 0.88rem;
    }
    
    .sidebar-collapse-btn i {
        font-size: 0.85rem;
        margin-right: 8px;
    }
    
    .collapse-control {
        font-size: 0.7rem !important;
    }
}

@media (max-width: 400px) {
    #sidebar,
    .admin-sidebar {
        width: 220px;
        max-width: 220px;
    }
    
    #sidebar.show,
    .admin-sidebar.show {
        width: 220px;
        max-width: 220px;
    }
    
    .sidebar-header {
        padding: 12px 12px;
    }
    
    .sidebar-header h3 {
        font-size: 0.95rem;
    }
    
    .nav-link {
        padding: 8px 12px;
        font-size: 0.86rem;
    }
    
    .nav-link i {
        font-size: 0.95rem;
        margin-right: 8px;
    }
    
    .submenu .nav-link {
        padding: 8px 12px 8px 24px;
        font-size: 0.82rem;
        min-height: 42px;
    }
}

/* ============================================================
   competition 项目定制（在源力标准基础上扩展）
   ============================================================ */

/* — 侧栏从顶部开始（品牌区在侧栏内，区别于 www 项目品牌在顶栏）— */
#sidebar.admin-sidebar,
.admin-sidebar {
    top: 0;
    height: 100vh;
    width: var(--sidebar-width);
}

/* — 品牌区（侧栏顶部，含图标 + 标题）— 高度与 header 58px 精确对齐 — */
.admin-sidebar .sidebar-header {
    padding: 0 14px;
    border-bottom: 1px solid var(--sidebar-border);
    display: flex;
    align-items: center;
    gap: 10px;
    height: 58px;
    flex-shrink: 0;
}
.admin-sidebar .sidebar-brand-icon {
    flex-shrink: 0;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #1664ff, #387bff);
    color: #fff;
    border-radius: 8px;
    box-shadow: 0 2px 6px rgba(22, 100, 255, 0.28);
}
.admin-sidebar .sidebar-brand-icon i.bi {
    font-size: 16px;
    line-height: 1;
    color: #fff !important;
}
.admin-sidebar .sidebar-brand-text {
    flex-grow: 1;
    overflow: hidden;
}
.admin-sidebar .sidebar-brand-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--sidebar-text-strong);
    line-height: 1.3;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* — 分组标签（对齐 cust head.php 内联样式：.72rem / 600 / letter-spacing / 顶部分割线）— */
.admin-sidebar .menu-group-label {
    font-size: .72rem;
    font-weight: 600;
    letter-spacing: .06em;
    color: #8a97a6;
    padding: 16px 20px 6px;
    margin-top: 4px;
    border-top: 1px solid rgba(0, 0, 0, .07);
    user-select: none;
    list-style: none;
}
.admin-sidebar .menu-group-label.first {
    border-top: none;
    margin-top: 0;
    padding-top: 10px;
}

/* — 菜单项：严格对齐 www legacy/cust/layout/head.php（2026-09-24 修正）—
   www 侧规则为 #menuContainer .nav-link { margin: 1px 10px; border-radius: 8px; }，
   左右内边距与图标间距一律沿用 yl-sidebar 基础层（padding:12px 16px / i margin-right:12px）。
   切勿在此收紧左右边距：曾用 margin 1px 8px + padding 10px，会让菜单整体比 www 左移。 */
.admin-sidebar .nav-item {
    margin: 0;
}
.admin-sidebar .nav-link {
    margin: 1px 10px;
    border-radius: 8px;
}

/* — 赛事工作台品牌区副标题（event/layout.php 用同一套 .sidebar-brand-* 结构 + 一行副标题）— */
.admin-sidebar .sidebar-brand-sub {
    font-size: 11px;
    line-height: 1.25;
    color: #8a97a6;
}