/**
 * 導航側邊欄企業風格樣式 (Enhanced Version)
 * Navigation Sidebar Corporate Styling with Improved Layout & UX
 * 
 * 改進項目:
 * - 更好的視覺層次和間距
 * - 改善的互動反饋和動畫
 * - 優化的響應式設計
 * - 增強的無障礙支援
 * - 更清晰的資訊架構
 */

/* 主要導航容器 - 增強版 */
.sb-sidenav {
    background: linear-gradient(180deg, #0085CA 0%, #006FA3 100%) !important;
    box-shadow: 2px 0 12px rgba(0, 0, 0, 0.12), inset -1px 0 0 rgba(255, 255, 255, 0.1);
    border-right: none;
    width: 240px;
    position: relative;
    overflow-x: hidden;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    z-index: 1020 !important; /* Ensure sidebar stays below top menu (z-index: 1030) */
}

/* 大螢幕時確保側邊欄完全可見且可點擊 */
@media (min-width: 992px) {
    .sb-sidenav {
        visibility: visible !important;
        pointer-events: auto !important;
        transform: translateX(0) !important;
    }
}

/* 確保側邊欄容器層級低於頂部選單 */
#layoutSidenav_nav {
    z-index: 1020 !important; /* Below top menu (1030) */
}

/* 側邊欄載入狀態 */
.sb-sidenav::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 2px;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
    animation: shimmer 2s infinite;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.sb-sidenav.loading::before {
    opacity: 1;
}

@keyframes shimmer {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(100%); }
}

.sb-sidenav-light {
    background: #0085CA !important;
}

/* 側邊欄 Logo 區域 - 企業正式風格增強版 */
.sb-sidenav-logo {
    padding: 1.75rem 1.5rem 1.25rem;
    text-align: center;
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
    margin-bottom: 0.5rem;
    background: linear-gradient(180deg, rgba(255,255,255,0.08) 0%, rgba(255,255,255,0.02) 100%);
    position: relative;
    backdrop-filter: blur(10px);
}

.sb-sidenav-logo::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 60%;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    transform: translateX(-50%);
}

.sb-sidenav-logo a {
    display: block;
    text-decoration: none;
}

/* 企業級 Logo 樣式 */
.sidebar-logo {
    max-width: 140px;
    height: auto;
    max-height: 45px;
    /* 純白色專業外觀 */
    filter: brightness(0) invert(1);
    transition: all 0.3s ease;
    /* 添加輕微陰影增加層次感 */
    drop-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.sidebar-logo:hover {
    /* 企業級懸停效果：更含蓄 */
    opacity: 0.9;
    transform: translateY(-1px);
    filter: brightness(0) invert(1) drop-shadow(0 4px 8px rgba(0, 0, 0, 0.15));
}

/* 選單區域 */
.sb-sidenav-menu {
    padding: 0;
}

.sb-sidenav .nav {
    flex-direction: column;
    padding: 0.5rem 0;
}

/* 選單標題 - 改進版本 */
.sb-sidenav-menu-heading {
    padding: 1.25rem 1.5rem 0.75rem;
    font-size: 0.7rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: rgba(255, 255, 255, 0.9);
    background: linear-gradient(90deg, rgba(255, 255, 255, 0.08), rgba(255, 255, 255, 0.02));
    border-bottom: none;
    margin-bottom: 0.25rem;
    position: relative;
    overflow: hidden;
}

.sb-sidenav-menu-heading::before {
    content: '';
    position: absolute;
    left: 0;
    bottom: 0;
    width: 40px;
    height: 2px;
    background: rgba(255, 255, 255, 0.4);
    border-radius: 1px;
}

/* 第一個標題上方不需要額外間距 */
.sb-sidenav-menu-heading:first-of-type {
    padding-top: 0.75rem;
    margin-top: 0.5rem;
}

/* 選單連結基本樣式 - 增強版 */
.sb-sidenav .nav-link {
    display: flex;
    align-items: center;
    padding: 0.875rem 1.5rem;
    color: rgba(255, 255, 255, 0.95) !important;
    text-decoration: none;
    transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    border-left: 3px solid transparent;
    position: relative;
    font-size: 0.875rem;
    font-weight: 500;
    margin: 0.125rem 0.5rem;
    border-radius: 0 8px 8px 0;
    backdrop-filter: blur(10px);
    min-height: 44px;
}

/* 選單連結前綴線條 */
.sb-sidenav .nav-link::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    width: 0;
    height: 0;
    background: #FFFFFF;
    border-radius: 0 2px 2px 0;
    transform: translateY(-50%);
    transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

/* 選單連結懸停前綴效果 */
.sb-sidenav .nav-link:hover::before {
    width: 3px;
    height: 20px;
}

/* 選單連結圖示 */
.sb-nav-link-icon {
    width: 20px;
    height: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: 0.75rem;
    font-size: 0.9rem;
    color: #FFFFFF !important;
    transition: all 0.2s ease;
}

/* 強制所有圖示為白色，確保可見度 */
.sb-nav-link-icon i,
.sb-nav-link-icon .fa,
.sb-nav-link-icon .fas,
.sb-nav-link-icon .far,
.sb-nav-link-icon .fab {
    color: #FFFFFF !important;
}

/* 摺疊箭頭 */
.sb-sidenav-collapse-arrow {
    margin-left: auto;
    transition: transform 0.2s ease;
}

.sb-sidenav-collapse-arrow i {
    font-size: 0.8rem;
    color: #FFFFFF;
}

/* 選單連結懸停效果 - 增強版 */
.sb-sidenav .nav-link:hover {
    background: linear-gradient(90deg, rgba(255, 255, 255, 0.15), rgba(255, 255, 255, 0.08));
    border-left-color: #ffffff;
    color: #ffffff !important;
    transform: translateX(4px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1), inset 0 1px 0 rgba(255, 255, 255, 0.2);
}

/* 選單連結焦點效果增強 */
.sb-sidenav .nav-link:focus {
    outline: 2px solid rgba(255, 255, 255, 0.6);
    outline-offset: -2px;
    background: linear-gradient(90deg, rgba(255, 255, 255, 0.2), rgba(255, 255, 255, 0.1));
    border-radius: 0 6px 6px 0;
}

.sb-sidenav .nav-link:hover .sb-nav-link-icon {
    color: #ffffff !important;
}

.sb-sidenav .nav-link:hover .sb-nav-link-icon i,
.sb-sidenav .nav-link:hover .sb-nav-link-icon .fa,
.sb-sidenav .nav-link:hover .sb-nav-link-icon .fas,
.sb-sidenav .nav-link:hover .sb-nav-link-icon .far,
.sb-sidenav .nav-link:hover .sb-nav-link-icon .fab {
    color: #ffffff !important;
}

.sb-sidenav .nav-link:hover .sb-sidenav-collapse-arrow i {
    color: #ffffff !important;
}

/* 展開狀態的選單項目 */
.sb-sidenav .nav-link[aria-expanded="true"] {
    background: rgba(255, 255, 255, 0.15);
    border-left-color: #ffffff;
    color: #ffffff !important;
}

.sb-sidenav .nav-link[aria-expanded="true"] .sb-sidenav-collapse-arrow {
    transform: rotate(180deg);
}

.sb-sidenav .nav-link[aria-expanded="true"] .sb-nav-link-icon {
    color: #ffffff !important;
}

.sb-sidenav .nav-link[aria-expanded="true"] .sb-nav-link-icon i,
.sb-sidenav .nav-link[aria-expanded="true"] .sb-nav-link-icon .fa,
.sb-sidenav .nav-link[aria-expanded="true"] .sb-nav-link-icon .fas,
.sb-sidenav .nav-link[aria-expanded="true"] .sb-nav-link-icon .far,
.sb-sidenav .nav-link[aria-expanded="true"] .sb-nav-link-icon .fab {
    color: #ffffff !important;
}

/* 摺疊區域 - 增強版 */
.sb-sidenav .collapse {
    background: linear-gradient(180deg, rgba(0, 0, 0, 0.08), rgba(0, 0, 0, 0.12));
    border-left: 2px solid rgba(255, 255, 255, 0.25);
    margin-left: 0.75rem;
    margin-right: 0.5rem;
    border-radius: 0 0 8px 8px;
    overflow: hidden;
    backdrop-filter: blur(5px);
    box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.1);
    position: relative;
}

/* 摺疊指示器 */
.sb-sidenav .collapse::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 2px;
    background: linear-gradient(90deg, rgba(255, 255, 255, 0.3), transparent);
}

/* 摺疊區域動畫 */
.sb-sidenav .collapse.show {
    animation: expandDown 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes expandDown {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 巢狀選單 - 改進版本 */
.sb-sidenav-menu-nested {
    padding: 0.25rem 0 0.5rem;
    background: rgba(0, 0, 0, 0.05);
    border-radius: 0 0 8px 0;
    margin-top: 0.25rem;
}

.sb-sidenav-menu-nested .nav-link {
    padding: 0.625rem 2.25rem;
    font-size: 0.8rem;
    color: rgba(255, 255, 255, 0.85) !important;
    border-left: none;
    position: relative;
    margin: 0.0625rem 0.75rem 0.0625rem 0.5rem;
    border-radius: 0 6px 6px 0;
    min-height: 36px;
}

.sb-sidenav-menu-nested .nav-link::before {
    content: '';
    position: absolute;
    left: 1.5rem;
    top: 50%;
    width: 4px;
    height: 4px;
    background: rgba(255, 255, 255, 0.6);
    border-radius: 50%;
    transform: translateY(-50%);
    transition: all 0.2s ease;
}

.sb-sidenav-menu-nested .nav-link:hover {
    background: rgba(255, 255, 255, 0.1);
    color: #FFFFFF !important;
}

.sb-sidenav-menu-nested .nav-link:hover::before {
    background: #FFFFFF;
    transform: translateY(-50%) scale(1.2);
}

/* 次級巢狀選單 */
.sb-sidenav-menu-nested .sb-sidenav-menu-nested {
    background: rgba(0, 0, 0, 0.05);
    margin-left: 1rem;
    border-left: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 4px;
}

.sb-sidenav-menu-nested .sb-sidenav-menu-nested .nav-link {
    padding-left: 3rem;
    font-size: 0.8rem;
}

.sb-sidenav-menu-nested .sb-sidenav-menu-nested .nav-link::before {
    left: 2.5rem;
    width: 3px;
    height: 3px;
}

/* 響應式設計 - 增強版 */
@media (max-width: 1199.98px) {
    .sb-sidenav {
        width: 220px;
    }
    
    .sb-sidenav .nav-link {
        padding: 0.8rem 1.25rem;
        font-size: 0.85rem;
    }
}

@media (max-width: 991.98px) {
    .sb-sidenav {
        width: 100% !important;
        position: fixed;
        z-index: 1020;
        left: -100% !important; /* 使用 left 屬性完全移出螢幕 */
        transform: none !important; /* 移除 transform，避免部分可見 */
        transition: left 0.3s cubic-bezier(0.4, 0, 0.2, 1), visibility 0.3s ease;
        visibility: hidden !important; /* 預設不可見 */
        pointer-events: none !important; /* 預設不可點擊 */
        opacity: 0; /* 額外的透明度保護 */
    }
    
    .sb-sidenav.show {
        left: 0 !important;
        visibility: visible !important;
        pointer-events: auto !important;
        opacity: 1;
    }
    
    /* 當 body 沒有 sb-sidenav-toggled class 時隱藏側邊欄 (預設狀態) */
    body:not(.sb-sidenav-toggled) .sb-sidenav {
        left: -100% !important; /* 完全移出螢幕 */
        pointer-events: none !important; /* 禁用滑鼠點擊事件 */
        visibility: hidden !important; /* 完全隱藏元素 */
        opacity: 0 !important; /* 完全透明 */
    }
    
    /* 當 body 有 sb-sidenav-toggled class 時顯示側邊欄 (點擊 toggle 後) */
    body.sb-sidenav-toggled .sb-sidenav {
        left: 0 !important; /* 移回可見位置 */
        pointer-events: auto !important; /* 恢復滑鼠點擊事件 */
        visibility: visible !important; /* 恢復可見性 */
        opacity: 1 !important; /* 完全不透明 */
    }
    
    .sb-sidenav .nav-link {
        padding: 1rem 1.25rem;
        font-size: 0.9rem;
        min-height: 48px;
    }
    
    .sb-sidenav-menu-nested .nav-link {
        padding: 0.75rem 2rem;
        min-height: 40px;
    }
    
    /* 行動裝置遮罩 */
    .sb-sidenav-overlay {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background: rgba(0, 0, 0, 0.5);
        z-index: 1019;
        opacity: 0;
        visibility: hidden;
        transition: all 0.3s ease;
    }
    
    .sb-sidenav-overlay.show {
        opacity: 1;
        visibility: visible;
    }
}

@media (max-width: 575.98px) {
    .sb-sidenav {
        width: 90% !important;
        max-width: 280px;
    }
    
    .sb-sidenav .nav-link {
        padding: 1.125rem 1rem;
        min-height: 52px;
    }
    
    .sb-sidenav-menu-nested .nav-link {
        padding: 0.875rem 1.75rem;
        min-height: 44px;
    }
}


/* 滾動條美化增強 */
.sb-sidenav::-webkit-scrollbar {
    width: 8px;
}

.sb-sidenav::-webkit-scrollbar-track {
    background: rgba(0, 0, 0, 0.08);
    border-radius: 4px;
    margin: 0.5rem 0;
}

.sb-sidenav::-webkit-scrollbar-thumb {
    background: linear-gradient(180deg, rgba(255, 255, 255, 0.25), rgba(255, 255, 255, 0.15));
    border-radius: 4px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: all 0.2s ease;
}

.sb-sidenav::-webkit-scrollbar-thumb:hover {
    background: linear-gradient(180deg, rgba(255, 255, 255, 0.35), rgba(255, 255, 255, 0.25));
    border-color: rgba(255, 255, 255, 0.2);
    transform: scaleY(1.05);
}

.sb-sidenav::-webkit-scrollbar-thumb:active {
    background: linear-gradient(180deg, rgba(255, 255, 255, 0.45), rgba(255, 255, 255, 0.35));
}

/* Firefox 滾動條樣式 */
.sb-sidenav {
    scrollbar-width: thin;
    scrollbar-color: rgba(255, 255, 255, 0.2) rgba(0, 0, 0, 0.08);
}


/* 活動狀態 - 增強版 */
.sb-sidenav .nav-link.active {
    background: linear-gradient(90deg, rgba(255, 255, 255, 0.25), rgba(255, 255, 255, 0.15)) !important;
    border-left-color: #ffffff !important;
    color: #ffffff !important;
    font-weight: 600;
    transform: translateX(2px);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15), inset 0 1px 0 rgba(255, 255, 255, 0.3);
    position: relative;
}

.sb-sidenav .nav-link.active::after {
    content: '';
    position: absolute;
    right: 0;
    top: 0;
    width: 2px;
    height: 100%;
    background: rgba(255, 255, 255, 0.4);
    border-radius: 1px 0 0 1px;
}

/* 防止翻譯閃爍 - 增強版 */
/* 初始狀態：完全隱藏未翻譯的元素 */
[data-i18n]:not(.i18n-loaded) {
    opacity: 0 !important;
    visibility: hidden !important;
    transform: translateY(10px);
    transition: opacity 0.3s ease-out, visibility 0s linear 0.3s, transform 0.3s ease-out;
}

/* 翻譯完成狀態：平滑顯示 */
[data-i18n].i18n-loaded {
    opacity: 1 !important;
    visibility: visible !important;
    transform: translateY(0);
    transition: opacity 0.3s ease-out, visibility 0s linear 0s, transform 0.3s ease-out;
}

/* 載入時完全隱藏側邊欄翻譯內容，避免閃爍 */
.sb-sidenav-menu:not(.i18n-initialized) [data-i18n] {
    opacity: 0 !important;
    visibility: hidden !important;
    position: relative;
}

/* 初始化完成後直接顯示，不要動畫 */
.sb-sidenav-menu.i18n-initialized [data-i18n] {
    opacity: 1 !important;
    visibility: visible !important;
    transition: opacity 0.2s ease-in-out;
}

/* 添加載入指示器，在翻譯完成前顯示 */
.sb-sidenav-menu:not(.i18n-initialized)::before {
    content: '';
    position: absolute;
    top: 50px;
    left: 50%;
    width: 20px;
    height: 20px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-top: 2px solid rgba(255, 255, 255, 0.8);
    border-radius: 50%;
    transform: translateX(-50%);
    animation: loadingSpinner 1s linear infinite;
    z-index: 10;
}

.sb-sidenav-menu.i18n-initialized::before {
    display: none;
}

@keyframes loadingSpinner {
    0% { transform: translateX(-50%) rotate(0deg); }
    100% { transform: translateX(-50%) rotate(360deg); }
}

/* 移除漸進式動畫延遲，直接顯示 */

/* 移除 slideInUp 動畫，使用簡單的淡入效果 */
@keyframes simpleAppear {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

/* 載入骨架屏效果 */
.sb-sidenav.skeleton {
    position: relative;
    overflow: hidden;
}

.sb-sidenav.skeleton::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(
        90deg,
        rgba(255, 255, 255, 0.05) 0%,
        rgba(255, 255, 255, 0.1) 50%,
        rgba(255, 255, 255, 0.05) 100%
    );
    animation: skeletonShimmer 2s infinite;
    pointer-events: none;
}

@keyframes skeletonShimmer {
    0% {
        background-position: -400% 0;
    }
    100% {
        background-position: 400% 0;
    }
}

.sb-sidenav .nav-link.active .sb-nav-link-icon {
    color: #ffffff !important;
}

.sb-sidenav .nav-link.active .sb-nav-link-icon i,
.sb-sidenav .nav-link.active .sb-nav-link-icon .fa,
.sb-sidenav .nav-link.active .sb-nav-link-icon .fas,
.sb-sidenav .nav-link.active .sb-nav-link-icon .far,
.sb-sidenav .nav-link.active .sb-nav-link-icon .fab {
    color: #ffffff !important;
}

/* 選單項目焦點效果增強 */
.sb-sidenav .nav-link:focus {
    outline: none;
    box-shadow: inset 0 0 0 2px rgba(255, 255, 255, 0.4), 0 0 0 2px rgba(255, 255, 255, 0.2);
    border-radius: 0 6px 6px 0;
    background: linear-gradient(90deg, rgba(255, 255, 255, 0.15), rgba(255, 255, 255, 0.08));
}

/* 無障礙設計增強 */
@media (prefers-reduced-motion: reduce) {
    .sb-sidenav,
    .sb-sidenav *,
    .sb-sidenav *::before,
    .sb-sidenav *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        transition-delay: 0ms !important;
        transform: none !important;
    }
}

/* 高對比度模式支援 */
@media (prefers-contrast: high) {
    .sb-sidenav {
        background: #000080 !important;
        border-right: 2px solid #FFFFFF;
    }
    
    .sb-sidenav .nav-link {
        color: #FFFFFF !important;
        border-left-color: #FFFFFF;
    }
    
    .sb-sidenav .nav-link:hover,
    .sb-sidenav .nav-link:focus {
        background: #FFFFFF !important;
        color: #000000 !important;
    }
}

/* 深色模式準備 */
@media (prefers-color-scheme: dark) {
    .sb-sidenav.dark-mode {
        background: linear-gradient(180deg, #1A1A1A 0%, #0D0D0D 100%) !important;
        box-shadow: 2px 0 12px rgba(0, 0, 0, 0.3);
    }
}

/* 工具提示樣式 */
.sb-sidenav [data-tooltip] {
    position: relative;
}

.sb-sidenav [data-tooltip]:hover::after {
    content: attr(data-tooltip);
    position: absolute;
    left: 100%;
    top: 50%;
    transform: translateY(-50%);
    background: rgba(0, 0, 0, 0.9);
    color: #FFFFFF;
    padding: 0.5rem 0.75rem;
    border-radius: 4px;
    font-size: 0.75rem;
    white-space: nowrap;
    z-index: 1000;
    margin-left: 0.5rem;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
    animation: tooltipFadeIn 0.2s ease;
}

.sb-sidenav [data-tooltip]:hover::before {
    content: '';
    position: absolute;
    left: 100%;
    top: 50%;
    transform: translateY(-50%);
    border: 4px solid transparent;
    border-right-color: rgba(0, 0, 0, 0.9);
    z-index: 1001;
}

@keyframes tooltipFadeIn {
    from { opacity: 0; transform: translateY(-50%) translateX(-5px); }
    to { opacity: 1; transform: translateY(-50%) translateX(0); }
}

/* 搜尋高亮 */
.sb-sidenav .nav-link.search-highlight {
    background: rgba(255, 193, 7, 0.2) !important;
    animation: searchPulse 1s ease-in-out infinite alternate;
}

@keyframes searchPulse {
    from { background: rgba(255, 193, 7, 0.2); }
    to { background: rgba(255, 193, 7, 0.35); }
}

/* 通知徽章 */
.sb-sidenav .nav-link .notification-badge {
    position: absolute;
    top: 0.5rem;
    right: 1rem;
    min-width: 16px;
    height: 16px;
    background: #DC3545;
    color: #FFFFFF;
    border-radius: 8px;
    font-size: 0.6rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px solid rgba(255, 255, 255, 0.2);
    animation: badgePulse 2s ease-in-out infinite;
}

@keyframes badgePulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.1); }
}

/* ================================
   專業 SKELETON 載入效果
   Enterprise-Grade Loading Skeleton
================================ */

/* 側邊欄 Skeleton 容器 */
.sidebar-skeleton-container {
    position: absolute;
    top: 0;
    left: 0;
    width: 240px;
    height: 100vh;
    background: linear-gradient(180deg, #0085CA 0%, #006FA3 100%);
    z-index: 1021;
    opacity: 1;
    visibility: visible;
    transition: opacity 0.3s ease-in-out, visibility 0.3s ease-in-out;
    overflow-y: auto;
    box-shadow: 2px 0 12px rgba(0, 0, 0, 0.12);
}

/* Skeleton 選單容器 */
.skeleton-menu {
    padding: 1rem 0;
    animation: skeletonFadeIn 0.6s ease-out;
}

/* Skeleton 標題 */
.skeleton-heading {
    height: 12px;
    background: linear-gradient(
        90deg,
        rgba(255, 255, 255, 0.08) 25%,
        rgba(255, 255, 255, 0.15) 50%,
        rgba(255, 255, 255, 0.08) 75%
    );
    background-size: 400% 100%;
    animation: skeletonShimmer 2s ease-in-out infinite;
    border-radius: 6px;
    margin: 1.25rem 1.5rem 1rem;
    width: 60%;
}

/* Skeleton 選單項目 */
.skeleton-menu-item {
    display: flex;
    align-items: center;
    padding: 0.875rem 1.5rem;
    margin: 0.125rem 0.5rem;
    gap: 0.75rem;
    border-radius: 0 8px 8px 0;
    animation-delay: var(--delay, 0ms);
}

/* Skeleton 圖示 */
.skeleton-icon {
    width: 20px;
    height: 20px;
    background: linear-gradient(
        90deg,
        rgba(255, 255, 255, 0.12) 25%,
        rgba(255, 255, 255, 0.20) 50%,
        rgba(255, 255, 255, 0.12) 75%
    );
    background-size: 400% 100%;
    animation: skeletonShimmer 2s ease-in-out infinite;
    border-radius: 4px;
    flex-shrink: 0;
}

/* Skeleton 文字區塊 */
.skeleton-text {
    height: 14px;
    background: linear-gradient(
        90deg,
        rgba(255, 255, 255, 0.10) 25%,
        rgba(255, 255, 255, 0.18) 50%,
        rgba(255, 255, 255, 0.10) 75%
    );
    background-size: 400% 100%;
    animation: skeletonShimmer 2s ease-in-out infinite;
    border-radius: 4px;
    flex: 1;
}

/* 不同長度的文字 */
.skeleton-text-short {
    width: 40%;
    max-width: 80px;
}

.skeleton-text-medium {
    width: 60%;
    max-width: 120px;
}

.skeleton-text-long {
    width: 80%;
    max-width: 150px;
}

/* Skeleton 箭頭（摺疊指示器） */
.skeleton-arrow {
    width: 12px;
    height: 12px;
    background: linear-gradient(
        90deg,
        rgba(255, 255, 255, 0.10) 25%,
        rgba(255, 255, 255, 0.18) 50%,
        rgba(255, 255, 255, 0.10) 75%
    );
    background-size: 400% 100%;
    animation: skeletonShimmer 2s ease-in-out infinite;
    border-radius: 2px;
    margin-left: auto;
}

/* 可摺疊項目 Skeleton */
.skeleton-collapsible {
    margin: 0.25rem 0;
    position: relative;
}

.skeleton-collapsible::before {
    content: '';
    position: absolute;
    left: 1rem;
    right: 1rem;
    bottom: -0.125rem;
    height: 1px;
    background: rgba(255, 255, 255, 0.08);
}

/* Skeleton 動畫已在上方定義，移除重複 */

@keyframes skeletonFadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 漸進式載入動畫 */
.skeleton-menu-item:nth-child(1) { animation: skeletonItemAppear 0.4s ease-out 0.1s both; }
.skeleton-menu-item:nth-child(2) { animation: skeletonItemAppear 0.4s ease-out 0.2s both; }
.skeleton-menu-item:nth-child(3) { animation: skeletonItemAppear 0.4s ease-out 0.3s both; }
.skeleton-menu-item:nth-child(4) { animation: skeletonItemAppear 0.4s ease-out 0.4s both; }
.skeleton-menu-item:nth-child(5) { animation: skeletonItemAppear 0.4s ease-out 0.5s both; }
.skeleton-menu-item:nth-child(6) { animation: skeletonItemAppear 0.4s ease-out 0.6s both; }
.skeleton-menu-item:nth-child(7) { animation: skeletonItemAppear 0.4s ease-out 0.7s both; }
.skeleton-menu-item:nth-child(8) { animation: skeletonItemAppear 0.4s ease-out 0.8s both; }

.skeleton-heading:nth-child(1) { animation: skeletonItemAppear 0.4s ease-out 0.05s both; }
.skeleton-heading:nth-child(6) { animation: skeletonItemAppear 0.4s ease-out 0.55s both; }

.skeleton-collapsible { animation: skeletonItemAppear 0.4s ease-out 0.65s both; }

@keyframes skeletonItemAppear {
    from {
        opacity: 0;
        transform: translateX(-10px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

/* 響應式設計 */
@media (max-width: 1199.98px) {
    .sidebar-skeleton-container {
        width: 220px;
    }
}

@media (max-width: 991.98px) {
    .sidebar-skeleton-container {
        width: 100%;
        left: -100% !important; /* 使用 left 屬性完全移出螢幕 */
        transform: none !important; /* 移除 transform */
        transition: left 0.3s cubic-bezier(0.4, 0, 0.2, 1), opacity 0.3s ease-in-out;
        visibility: hidden !important;
        pointer-events: none !important;
        opacity: 0;
    }
    
    .sidebar-skeleton-container.show {
        left: 0 !important;
        visibility: visible !important;
        pointer-events: auto !important;
        opacity: 1;
    }
    
    /* Skeleton 容器也要遵循相同的 toggle 邏輯 */
    body:not(.sb-sidenav-toggled) .sidebar-skeleton-container {
        left: -100% !important; /* 完全移出螢幕 */
        pointer-events: none !important; /* 禁用滑鼠點擊事件 */
        visibility: hidden !important; /* 完全隱藏元素 */
        opacity: 0 !important; /* 完全透明 */
    }
    
    body.sb-sidenav-toggled .sidebar-skeleton-container {
        left: 0 !important; /* 移回可見位置 */
        pointer-events: auto !important; /* 恢復滑鼠點擊事件 */
        visibility: visible !important; /* 恢復可見性 */
        opacity: 1 !important; /* 完全不透明 */
    }
}

@media (max-width: 575.98px) {
    .sidebar-skeleton-container {
        width: 90%;
        max-width: 280px;
    }
}

/* 減少動畫偏好設定支援 */
@media (prefers-reduced-motion: reduce) {
    .skeleton-menu,
    .skeleton-menu-item,
    .skeleton-heading,
    .skeleton-collapsible {
        animation: none;
    }
    
    .skeleton-icon,
    .skeleton-text,
    .skeleton-arrow {
        animation: none;
        background: rgba(255, 255, 255, 0.15);
    }
}

/* 高對比度模式支援 */
@media (prefers-contrast: high) {
    .sidebar-skeleton-container {
        background: #000080;
        border-right: 2px solid #FFFFFF;
    }
    
    .skeleton-icon,
    .skeleton-text,
    .skeleton-arrow,
    .skeleton-heading {
        background: rgba(255, 255, 255, 0.3);
        animation: none;
    }
}