/* =========================================
           1. CSS 變數系統 (Light / Dark)
           ========================================= */
        :root {
            /* Light Mode */
            --bg-body: #F3F4F6;
            --bg-sidebar: #FFFFFF;
            --bg-card: #FFFFFF;
            --bg-header: #FFFFFF;
            --text-primary: #1F2937;
            --text-secondary: #6B7280;
            --primary-color: #1a237e;
            --active-bg: #1e3a8a;
            --border-color: #E5E7EB;
            --card-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
            --sidebar-width: 96px;
            
            /* Toggle Switch Colors */
            --toggle-bg: #F3F4F6;
            --toggle-active: #FFFFFF;
            --toggle-icon: #6B7280;
            --toggle-active-icon: #1a237e;
        }

        [data-theme="dark"] {
            --bg-body: #111827;       /* 深灰背景 */
            --bg-sidebar: #1F2937;    /* 側邊欄深色 */
            --bg-card: #1F2937;       /* 卡片深色 */
            --bg-header: #1F2937;     /* Header 深色 */
            --text-primary: #F9FAFB;  /* 幾近白 */
            --text-secondary: #9CA3AF;/* 淺灰 */
            --primary-color: #818cf8; /* 較亮的藍紫色 */
            --active-bg: #3730a3;     
            --border-color: #374151;  /* 深色邊框 */
            --card-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.5);

            --toggle-bg: #374151;
            --toggle-active: #111827;
            --toggle-icon: #9CA3AF;
            --toggle-active-icon: #818cf8;
        }

        /* 基礎設定 */
        * { box-sizing: border-box; margin: 0; padding: 0; font-family: 'Segoe UI', sans-serif; transition: background-color 0.3s, color 0.3s, border-color 0.3s; }
        body { background-color: var(--bg-body); color: var(--text-primary); height: 100vh; overflow: hidden; display: flex; }

        /* 左側邊欄 */
        .sidebar {
            width: var(--sidebar-width);
            background-color: var(--bg-sidebar);
            border-right: 1px solid var(--border-color);
            display: flex; flex-direction: column; 
            padding: 24px 0; flex-shrink: 0; align-items: center;
            z-index: 20;
        }
        .logo-area { display: flex; flex-direction: column; align-items: center; gap: 6px; margin-bottom: 24px; text-align: center; color: var(--primary-color); }
        .logo-icon { font-size: 32px; line-height: 1; font-weight: 800; } 
        .logo-text { font-size: 12px; font-weight: 700; letter-spacing: 0.5px; }
        
        .nav-menu { width: 100%; flex: 1; display: flex; flex-direction: column; gap: 8px; }
        .nav-item { display: flex; flex-direction: column; align-items: center; gap: 4px; padding: 4px 0; color: var(--text-secondary); cursor: pointer; transition: 0.2s; width: 100%; position: relative; }
        .nav-item .icon-wrapper { width: 44px; height: 44px; display: flex; align-items: center; justify-content: center; font-size: 20px; border-radius: 10px; background-color: transparent; transition: all 0.2s; color: inherit; }
        .nav-item span { font-size: 11px; font-weight: 500; }
        
        /* Create Button Style */
        .nav-item.create-btn .icon-wrapper { border: 1.5px solid var(--text-secondary); border-radius: 50%; width: 32px; height: 32px; font-size: 14px; margin-bottom: 6px; }
        .nav-item.create-btn:hover .icon-wrapper { border-color: var(--primary-color); color: var(--primary-color); }
        
        /* Active / Hover States */
        .nav-item:not(.active):not(.create-btn):hover .icon-wrapper { background-color: var(--bg-body); color: var(--primary-color); }
        .nav-item:hover span { color: var(--text-primary); }
        .nav-item.active span { color: var(--primary-color); font-weight: 700; } 
        .nav-item.active .icon-wrapper { background-color: var(--primary-color); color: white; box-shadow: 0 4px 8px rgba(0,0,0, 0.2); }
        
        .nav-bottom { margin-top: auto; border-top: 1px solid var(--border-color); padding-top: 16px; width: 100%; gap: 4px; flex: 0; }

        /* 右側佈局 */
        .layout-right {
            flex: 1; display: flex; flex-direction: column; height: 100vh; overflow: hidden; background-color: var(--bg-body);
        }

        /* Header */
        header { 
            background-color: var(--bg-header); padding: 24px 48px; display: flex; justify-content: space-between; align-items: center; 
            border-bottom: 1px solid transparent; flex-shrink: 0; z-index: 10; box-shadow: 0 1px 2px rgba(0,0,0,0.05);
        }
        .greeting h2 { font-size: 14px; color: var(--text-secondary); font-weight: 400; margin-bottom: 4px; }
        .greeting h1 { font-size: 24px; font-weight: 700; color: var(--text-primary); }
        .header-actions { display: flex; gap: 16px; align-items: center; }

        /* Main Content */
        .main-content { 
            flex: 1; padding: 0; overflow-y: auto; display: flex; flex-direction: column; scrollbar-gutter: stable;
        }
        .content-body { padding: 24px 48px; flex: 1; }

        /* UI 元件 */
        .theme-switch { background-color: var(--toggle-bg); border: 1px solid var(--border-color); border-radius: 8px; padding: 4px; display: flex; gap: 4px; }
        .theme-btn { width: 32px; height: 32px; border: none; background: transparent; border-radius: 6px; cursor: pointer; color: var(--toggle-icon); display: flex; align-items: center; justify-content: center; font-size: 16px; transition: all 0.2s; }
        .theme-btn.active { background-color: var(--bg-card); color: var(--primary-color); box-shadow: 0 2px 4px rgba(0,0,0,0.1); }

        .lang-btn { width: 42px; height: 42px; border: 1px solid var(--border-color); background: var(--bg-card); border-radius: 8px; cursor: pointer; color: var(--text-secondary); font-size: 18px; display: flex; align-items: center; justify-content: center; }
        .lang-btn:hover { color: var(--primary-color); border-color: var(--primary-color); }

        /* Dropdowns */
        .lang-dropdown-container, .control-group { position: relative; }
        .dropdown-menu, .lang-dropdown, .create-dropdown, .card-dropdown {
            position: absolute; top: 100%; right: 0; background: var(--bg-card); border: 1px solid var(--border-color);
            border-radius: 8px; box-shadow: var(--card-shadow); padding: 8px; display: none; z-index: 50; margin-top: 8px; text-align: left;
        }
        .dropdown-menu.show, .lang-dropdown.show, .create-dropdown.show, .card-dropdown.show { display: block; animation: fadeIn 0.2s ease-out; }
        
        .lang-dropdown { width: 150px; top: 50px; }
        .lang-option { padding: 10px 16px; cursor: pointer; font-size: 14px; color: var(--text-primary); border-radius: 4px; }
        .lang-option:hover { background-color: var(--bg-body); color: var(--primary-color); }

        .create-dropdown { left: 70px; top: 0; right: auto; width: 180px; border-radius: 12px; z-index: 200; }
        .create-option { padding: 12px 16px; font-size: 14px; font-weight: 600; color: var(--text-primary); cursor: pointer; border-radius: 8px; display: flex; align-items: center; justify-content: space-between; }
        .create-option:hover { background-color: var(--bg-body); color: var(--primary-color); }

        .dropdown-menu { width: 200px; }
        .dropdown-header { font-size: 12px; font-weight: 700; color: var(--text-secondary); padding: 8px 12px 4px; text-transform: uppercase; }
        .filter-option, .sort-option { display: flex; align-items: center; gap: 8px; padding: 8px 12px; cursor: pointer; border-radius: 6px; font-size: 14px; color: var(--text-primary); }
        .filter-option:hover, .sort-option:hover { background-color: var(--bg-body); color: var(--primary-color); }
        .filter-option input[type="checkbox"] { accent-color: var(--primary-color); width: 16px; height: 16px; }
        .sort-option.selected { color: var(--primary-color); font-weight: 700; background-color: var(--bg-body); }

        .card-dropdown { width: 160px; padding: 6px; }
        .card-menu-item { padding: 8px 12px; font-size: 13px; color: var(--text-primary); border-radius: 4px; cursor: pointer; display: flex; align-items: center; gap: 8px; }
        .card-menu-item:hover { background-color: var(--bg-body); color: var(--primary-color); }
        .card-menu-item.danger:hover { background-color: #fee2e2; color: #ef4444; }

        /* Controls Bar */
        .section-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 20px; margin-top: 10px; }
        .section-title { font-size: 18px; font-weight: 700; color: var(--text-primary); }
        .controls-bar { display: flex; gap: 16px; }
        .search-box { background: var(--bg-card); border: 1px solid var(--border-color); border-radius: 8px; padding: 8px 12px; display: flex; align-items: center; gap: 8px; width: 300px; }
        .search-box input { border: none; outline: none; width: 100%; font-size: 14px; color: var(--text-primary); background: transparent; }
        .control-btn { background: var(--bg-card); border: 1px solid var(--border-color); padding: 8px 16px; border-radius: 8px; cursor: pointer; display: flex; align-items: center; gap: 6px; font-size: 14px; font-weight: 500; color: var(--text-secondary); }

        /* Grid & Card */
        .project-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 24px; margin-bottom: 48px; }
        .project-card { background: var(--bg-card); border: 1px solid var(--border-color); border-radius: 16px; padding: 16px; display: flex; flex-direction: column; gap: 12px; transition: transform 0.2s, box-shadow 0.2s; cursor: pointer; position: relative; }
        .project-card:hover { transform: translateY(-4px); box-shadow: var(--card-shadow); border-color: var(--primary-color); }
        
        .card-top { display: flex; justify-content: space-between; align-items: flex-start; }
        .tags { display: flex; gap: 6px; }
        .tag { font-size: 10px; padding: 4px 10px; border-radius: 12px; font-weight: 600; }
        .tag.tag-project { background: #FFF4E5; color: #FF9800; }
        .tag.tag-page { background: #E3F2FD; color: #2196F3; }
        .tag.tag-cat { background: var(--bg-body); color: var(--text-secondary); border: 1px solid var(--border-color); }
        
        [data-theme="dark"] .tag.tag-project { background: #431407; color: #fdba74; }
        [data-theme="dark"] .tag.tag-page { background: #172554; color: #93c5fd; }

        .card-title { font-size: 16px; font-weight: 700; margin: 4px 0; color: var(--text-primary); }
        .card-preview { width: 100%; height: 120px; background-color: var(--bg-body); border-radius: 8px; display: flex; align-items: center; justify-content: center; border: 1px solid var(--border-color); }
        .card-preview .placeholder { color: var(--text-secondary); font-size: 12px; }
        .card-footer { display: flex; justify-content: space-between; align-items: center; margin-top: auto; }
        .date { font-size: 11px; color: var(--text-secondary); }
        
        .card-actions { position: relative; }
        .card-menu-btn { width: 24px; height: 24px; display: flex; align-items: center; justify-content: center; border-radius: 4px; transition: background-color 0.2s; }
        .card-menu-btn:hover { background-color: var(--bg-body); color: var(--primary-color) !important; }
        
        .star-btn { padding: 4px; border-radius: 50%; transition: all 0.2s; display: inline-flex; }
        .star-btn:hover { background-color: rgba(0,0,0,0.05); transform: scale(1.1); }
        .star-btn.active { color: #fbbf24 !important; }

        @keyframes fadeIn { from { opacity: 0; transform: translateY(-5px); } to { opacity: 1; transform: translateY(0); } }

        /* 新增：Template 分類區塊樣式 */
        .template-category {
            margin-bottom: 40px; /* 每個分類之間的間距 */
        }
        
        .template-category .section-header {
            margin-bottom: 16px;
            border-bottom: 1px solid var(--border-color); /* 加個底線區隔 */
            padding-bottom: 8px;
        }

        .template-category .section-title {
            font-size: 16px; /* 稍微縮小標題 */
            color: var(--text-secondary);
            text-transform: uppercase;
            letter-spacing: 1px;
        }
        
        /* 確保卡片預覽圖填滿容器 */
        .card-preview {
            position: relative;
            width: 100%;
            height: 140px; /* 或你設定的高度 */
            background-color: var(--bg-body);
            overflow: hidden; /* 🚀 確保圓角效果 */
            display: flex;
            align-items: center;
            justify-content: center;
        }

        .card-img-preview {
            width: 100%;
            height: 100%;
            object-fit: cover;      /* 確保填滿容器 */
            object-position: top;   /* 🚀 關鍵修正：強制對齊圖片頂部，確保 Header 可見 */
        }

        /* 儀表板卡片預覽區修正 */
        .project-card .card-preview {
            height: 140px;            /* 確保高度足以容納圖片內容 */
            display: flex;
            align-items: center;      /* 垂直居中 */
            justify-content: center;  /* 水平居中 */
            background-color: #f8f9fa; 
            overflow: hidden;
            padding: 8px;             /* 留一點內距，避免圖片貼齊邊緣 */
        }

        .project-card .card-img-preview {
            width: 100%;
            height: 100%;
            /* 🚀 最重要的一行：contain 確保圖片完整顯示不被裁切 */
            object-fit: contain;      
        }