/* 左侧导航样式 - 增强版 */
:root {
    --nav-w: 240px;
    --collapsed-w: 60px;
    --nav-bg: #0d6efd;
    --nav-text: #fff;
    --nav-hover: #0b5ed7;
    --nav-active: #0a58ca;
    --nav-border: rgba(255,255,255,0.1);
    --nav-shadow: 0 0.125rem 0.25rem rgba(0,0,0,0.075);
}

/* 暗黑主题下的侧边栏颜色 */
[data-theme="dark"] {
    --nav-bg: var(--sidebar-bg);
    --nav-hover: var(--sidebar-hover);
    --nav-active: var(--sidebar-active);
    --nav-border: var(--sidebar-hover);
}

/* 重置和基础样式 */
* {
    box-sizing: border-box;
}

html, body {
    height: 100%;
    margin: 0;
    padding: 0;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    overflow-x: hidden;
}

/* 侧边栏容器 */
#sidebar {
    width: var(--nav-w);
    background: var(--nav-bg);
    color: var(--nav-text);
    position: fixed;
    height: 100vh;
    top: 0;
    left: 0;
    z-index: 1050;
    transition: width 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    overflow-y: auto;
    overflow-x: hidden;
    box-shadow: var(--nav-shadow);
}

#sidebar::-webkit-scrollbar {
    width: 6px;
}

#sidebar::-webkit-scrollbar-track {
    background: rgba(255,255,255,0.1);
}

#sidebar::-webkit-scrollbar-thumb {
    background: rgba(255,255,255,0.3);
    border-radius: 3px;
}

#sidebar::-webkit-scrollbar-thumb:hover {
    background: rgba(255,255,255,0.5);
}

/* 收起状态 */
#sidebar.collapsed {
    width: var(--collapsed-w);
}

/* 头部区域 */
.sidebar-header {
    padding: 1.25rem 1rem;
    border-bottom: 1px solid var(--nav-border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    min-height: 65px;
}

.sidebar-header .navbar-brand {
    color: var(--nav-text);
    text-decoration: none;
    font-size: 1.25rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    transition: opacity 0.2s ease;
    flex: 1;
}

.sidebar-header .navbar-brand:hover {
    color: var(--nav-text);
    opacity: 0.8;
}

.sidebar-header .navbar-brand i {
    font-size: 1.5rem;
    margin-right: 0.75rem;
}

/* 折叠按钮 */
.collapse-btn {
    background: rgba(255,255,255,0.1);
    border: none;
    color: var(--nav-text);
    width: 32px;
    height: 32px;
    border-radius: 0.375rem;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.2s ease;
    flex-shrink: 0;
}

.collapse-btn:hover {
    background: rgba(255,255,255,0.2);
    transform: scale(1.05);
}

.collapse-btn:active {
    transform: scale(0.95);
}

#sidebar.collapsed .collapse-btn {
    margin: 0 auto 0.5rem;
}

/* 导航区域 */
.sidebar-nav {
    flex: 1;
    padding: 0.75rem 0;
}

.sidebar-nav .nav-link {
    color: var(--nav-text);
    padding: 0.75rem 1rem;
    margin: 0.125rem 0.5rem;
    border-radius: 0.375rem;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    text-decoration: none;
    position: relative;
    overflow: hidden;
}

.sidebar-nav .nav-link:hover {
    background: var(--nav-hover);
    transform: translateX(2px);
}

.sidebar-nav .nav-link.active {
    background: var(--nav-active);
    font-weight: 500;
    box-shadow: none;
}


/* 暗黑主题下的激活菜单样式 */
[data-theme="dark"] .sidebar-nav .nav-link.active {
    background: rgba(255,255,255,0.2);
}


.sidebar-nav .nav-link i {
    font-size: 1.1rem;
    min-width: 24px;
    text-align: center;
    margin-right: 0.75rem;
}

.sidebar-nav .link-text {
    flex: 1;
    transition: opacity 0.3s ease, transform 0.3s ease;
}

.sidebar-nav .nav-link .bi-chevron-down,
.sidebar-nav .nav-link .bi-chevron-up {
    font-size: 0.8rem;
    margin-left: auto;
    margin-right: 0;
    transition: transform 0.3s ease;
}

/* 收起状态下的文本和图标处理 */
#sidebar.collapsed .link-text {
    opacity: 0;
    transform: translateX(-10px);
    display: none;
}

#sidebar.collapsed .nav-link {
    padding: 0.75rem;
    justify-content: center;
    text-align: center;
}

#sidebar.collapsed .nav-link i {
    margin-right: 0;
    font-size: 1.2rem;
}

#sidebar.collapsed .nav-link .bi-chevron-down,
#sidebar.collapsed .nav-link .bi-chevron-up {
    display: none;
}

/* 子菜单样式 */
.sidebar-submenu {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.sidebar-submenu.show {
    max-height: 400px;
}

.sidebar-submenu .nav-link {
    padding: 0.625rem 1rem 0.625rem 3.5rem;
    font-size: 0.9rem;
    background: rgba(0,0,0,0.1);
    margin: 0.125rem 0.5rem;
    border-left: 2px solid transparent;
}

.sidebar-submenu .nav-link:hover {
    background: rgba(255,255,255,0.1);
    transform: translateX(4px);
}

.sidebar-submenu .nav-link.active {
    background: rgba(255,255,255,0.15);
    border-left-color: #fff;
}

#sidebar.collapsed .sidebar-submenu {
    display: none;
}

/* 用户区域 */
.sidebar-user {
    border-top: 1px solid var(--nav-border);
    padding: 0.75rem;
    margin-top: auto;
}

.user-dropdown {
    position: relative;
}

.user-dropdown .dropdown-toggle {
    background: rgba(255,255,255,0.1);
    border: 1px solid rgba(255,255,255,0.2);
    color: var(--nav-text);
    padding: 0.75rem;
    width: 100%;
    text-align: left;
    display: flex;
    align-items: center;
    border-radius: 0.375rem;
    transition: all 0.2s ease;
}

.user-dropdown .dropdown-toggle:hover {
    background: rgba(255,255,255,0.2);
    transform: translateY(-1px);
}

.user-dropdown .dropdown-toggle i:first-child {
    font-size: 1.2rem;
    margin-right: 0.75rem;
}

.user-dropdown .dropdown-menu {
    position: absolute;
    bottom: 100%;
    left: 0;
    right: 0;
    background: var(--bg-elevated, #fff);
    border: 1px solid var(--border-color, #dee2e6);
    border-radius: 0.5rem;
    box-shadow: 0 0.5rem 1rem rgba(0,0,0,0.15);
    padding: 0.5rem 0;
    margin-bottom: 0.25rem;
}

.user-dropdown .dropdown-item {
    color: var(--text-primary, #333);
    padding: 0.5rem 1rem;
    transition: background 0.2s ease;
}

.user-dropdown .dropdown-item:hover {
    background: var(--bg-hover, #f8f9fa);
}

.user-dropdown .dropdown-item i {
    margin-right: 0.5rem;
    width: 16px;
    text-align: center;
}

/* 主内容区域 */
#main-content {
    margin-left: var(--nav-w);
    transition: margin-left 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

#main-content.expanded {
    margin-left: var(--collapsed-w);
}

/* 移动端顶部栏 */
.mobile-header {
    display: none;
    background: var(--nav-bg);
    color: var(--nav-text);
    padding: 0.75rem 1rem;
    align-items: center;
    justify-content: space-between;
    box-shadow: var(--nav-shadow);
    height: 60px;
}

.mobile-header .navbar-brand {
    color: var(--nav-text);
    text-decoration: none;
    font-size: 1.25rem;
    font-weight: 600;
    display: flex;
    align-items: center;
}

.mobile-header .navbar-brand:hover {
    color: var(--nav-text);
}

.mobile-header .navbar-brand i {
    margin-right: 0.5rem;
}

.sidebar-toggle {
    background: none;
    border: none;
    color: var(--nav-text);
    font-size: 1.5rem;
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 0.375rem;
    transition: background 0.2s ease;
}

.sidebar-toggle:hover {
    background: rgba(255,255,255,0.1);
}

.sidebar-toggle:active {
    transform: scale(0.95);
}

/* 内容区域 */
.content-wrapper {
    flex: 1;
    padding: 1.5rem;
    background: var(--bg-body, #f8f9fa);
    color: var(--text-primary, #212529);
    min-height: calc(100vh - 60px);
}

/* 遮罩层 */
.sidebar-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    z-index: 1040;
    backdrop-filter: blur(2px);
}

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

/* 响应式设计 */
@media (max-width: 768px) {
    #sidebar {
        transform: translateX(-100%);
        transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    }
    
    #sidebar.mobile-open {
        transform: translateX(0);
    }
    
    #main-content {
        margin-left: 0;
    }
    
    .mobile-header {
        display: flex;
    }
    
    .collapse-btn {
        display: none;
    }
    
    #sidebar.collapsed {
        width: var(--nav-w);
    }
    
    #sidebar.collapsed .link-text {
        opacity: 1;
        transform: translateX(0);
        display: block;
    }
    
    #sidebar.collapsed .nav-link {
        padding: 0.75rem 1rem;
        justify-content: flex-start;
        text-align: left;
    }
    
    #sidebar.collapsed .nav-link i {
        margin-right: 0.75rem;
    }
    
    .sidebar-submenu .nav-link {
        padding-left: 3rem;
    }
    
    .content-wrapper {
        padding: 1rem;
    }
}

@media (min-width: 769px) {
    .mobile-header {
        display: none;
    }
    
    #sidebar {
        transform: translateX(0);
    }
}

/* 平板端适配 */
@media (min-width: 769px) and (max-width: 1024px) {
    #sidebar {
        width: 200px;
    }
    
    #main-content {
        margin-left: 200px;
    }
    
    #sidebar.collapsed {
        width: var(--collapsed-w);
    }
    
    #main-content.expanded {
        margin-left: var(--collapsed-w);
    }
}

/* 大屏幕适配 */
@media (min-width: 1400px) {
    #sidebar {
        width: 260px;
    }
    
    #main-content {
        margin-left: 260px;
    }
    
    #sidebar.collapsed {
        width: var(--collapsed-w);
    }
    
    #main-content.expanded {
        margin-left: var(--collapsed-w);
    }
}

/* 动画和过渡效果 */
@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateX(-20px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.sidebar-nav .nav-link {
    animation: slideIn 0.3s ease backwards;
}

.sidebar-nav .nav-link:nth-child(1) { animation-delay: 0.05s; }
.sidebar-nav .nav-link:nth-child(2) { animation-delay: 0.1s; }
.sidebar-nav .nav-link:nth-child(3) { animation-delay: 0.15s; }
.sidebar-nav .nav-link:nth-child(4) { animation-delay: 0.2s; }
.sidebar-nav .nav-link:nth-child(5) { animation-delay: 0.25s; }

/* 可访问性增强 */
.sidebar-nav .nav-link:focus-visible {
    outline: 2px solid #fff;
    outline-offset: 2px;
}

.collapse-btn:focus-visible,
.sidebar-toggle:focus-visible {
    outline: 2px solid var(--nav-text);
    outline-offset: 2px;
}

/* 高对比度模式支持 */
@media (prefers-contrast: high) {
    :root {
        --nav-border: rgba(255,255,255,0.3);
    }
    
    .sidebar-nav .nav-link {
        border: 1px solid transparent;
    }
    
    .sidebar-nav .nav-link:hover,
    .sidebar-nav .nav-link.active {
        border-color: var(--nav-text);
    }
}

/* 减少动画偏好支持 */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}