/* --- Global Variables --- */
    :root {
        --hz-navy: #0F172A;
        --hz-orange: #ec682e;
        --hz-text: #334155;
        --hz-text-light: #94A3B8;
        --hz-border: #E2E8F0;
        --hz-bg-white: #FFFFFF;
        --hz-bg-light: #F8FAFC;
    }

    body { margin: 0; font-family: 'Open Sans', sans-serif; background-color: var(--hz-bg-light); color: var(--hz-text); }
    h1, h2, h3, p { margin: 0; }
    
    .dl-page-container { max-width: 1400px; margin: 0 auto; padding: 60px 40px; }
    .page-header { margin-bottom: 40px; }
    .breadcrumb { font-size: 0.9rem; color: var(--hz-text-light); margin-bottom: 10px; }
    .page-title { font-family: 'Poppins', sans-serif; font-size: 2.2rem; font-weight: 600; color: var(--hz-navy); }

    .dl-layout { display: flex; gap: 40px; align-items: flex-start; }

    /* Sidebar */
    .sidebar { width: 260px; flex-shrink: 0; background: var(--hz-bg-white); border-radius: 12px; padding: 20px 0; box-shadow: 0 4px 20px rgba(0,0,0,0.03); }
    .sidebar-title { font-family: 'Poppins', sans-serif; font-size: 1.1rem; font-weight: 600; color: var(--hz-navy); padding: 0 24px 16px 24px; border-bottom: 1px solid var(--hz-border); margin-bottom: 10px; }
    .cat-item { padding: 12px 24px; cursor: pointer; font-weight: 500; color: var(--hz-text); transition: all 0.2s ease; border-left: 3px solid transparent; display: flex; justify-content: space-between; align-items: center; }
    .cat-item:hover, .cat-item.active { background-color: #FFF7ED; color: var(--hz-orange); }
    .cat-item.active { border-left-color: var(--hz-orange); font-weight: 600; }

    /* Content */
    .content-area { flex: 1; background: var(--hz-bg-white); border-radius: 12px; padding: 30px; box-shadow: 0 4px 20px rgba(0,0,0,0.03); min-height: 600px; }
    .filter-bar { display: grid; grid-template-columns: 1fr 1fr 1.5fr; gap: 20px; margin-bottom: 30px; padding-bottom: 30px; border-bottom: 1px solid var(--hz-border); }
    .filter-group label { display: block; font-size: 0.85rem; font-weight: 600; color: var(--hz-navy); margin-bottom: 8px; font-family: 'Poppins', sans-serif; }
    .hz-select, .hz-input { width: 100%; padding: 12px 16px; border: 1px solid var(--hz-border); border-radius: 6px; font-family: 'Open Sans', sans-serif; font-size: 0.95rem; color: var(--hz-text); background-color: #fff; outline: none; transition: border 0.3s ease; box-sizing: border-box; }
    .hz-select:focus, .hz-input:focus { border-color: var(--hz-orange); box-shadow: 0 0 0 3px rgba(236, 104, 46, 0.1); }

    /* Table Header */
    .file-list-header { display: grid; grid-template-columns: 3fr 1.5fr 1fr 1.5fr; padding: 0 20px 15px 20px; border-bottom: 1px solid var(--hz-border); color: var(--hz-text-light); font-size: 0.85rem; font-weight: 600; text-transform: uppercase; }

    /* File Item */
    .file-item { display: grid; grid-template-columns: 3fr 1.5fr 1fr 1.5fr; align-items: center; padding: 20px; border-bottom: 1px solid var(--hz-border); transition: background 0.2s ease; }
    .file-item:last-child { border-bottom: none; }
    .file-item:hover { background-color: #FFF7ED; }

    .file-info { display: flex; align-items: center; gap: 15px; }
    .file-icon { width: 40px; height: 40px; background: #F1F5F9; border-radius: 8px; display: flex; align-items: center; justify-content: center; color: var(--hz-text-light); flex-shrink: 0; }
    
    /* Icon Colors */
    .icon-pdf { color: #E11D48; background: #FFF1F2; } /* 红色 PDF */
    .icon-zip { color: var(--hz-orange); background: #FFF7ED; } /* 橙色 ZIP */
    .icon-spec { color: #7C3AED; background: #F5F3FF; } /* 🟣 新增：紫色 Spec 图标 */
    .icon-doc { color: #059669; background: #ECFDF5; } /* 绿色 Doc 图标 */

    .file-name-wrap h4 { font-size: 1rem; font-weight: 600; color: var(--hz-navy); margin: 0 0 4px 0; font-family: 'Poppins', sans-serif; }
    .file-meta-sub { font-size: 0.8rem; color: var(--hz-text-light); }
    .col-model, .col-ver { font-size: 0.9rem; color: var(--hz-text); }

    .btn-dl { display: inline-flex; align-items: center; justify-content: center; gap: 8px; padding: 8px 20px; border: 1px solid var(--hz-orange); border-radius: 4px; color: var(--hz-orange); background: transparent; font-weight: 600; font-size: 0.9rem; cursor: pointer; transition: all 0.3s ease; text-decoration: none; width: fit-content; }
    .btn-dl:hover { background: var(--hz-orange); color: #fff; transform: translateY(-1px); box-shadow: 0 4px 10px rgba(236, 104, 46, 0.2); }

    .empty-state { text-align: center; padding: 60px; color: var(--hz-text-light); display: none; }

    @media (max-width: 900px) {
        .dl-layout { flex-direction: column; }
        .sidebar { width: 100%; overflow-x: auto; }
        .filter-bar { grid-template-columns: 1fr; }
        .file-list-header { display: none; }
        .file-item { grid-template-columns: 1fr; gap: 10px; position: relative; border: 1px solid var(--hz-border); border-radius: 8px; margin-bottom: 10px; }
        .btn-dl { width: 100%; }
    }