/* ============================================
   华纳环保 · 后台管理样式 (全面响应式升级版)
   ============================================ */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
:root {
    --admin-bg: #0F172A;
    --admin-surface: #1E293B;
    --admin-card: #334155;
    --admin-primary: #38BDF8;
    --admin-accent: #0EA5E9;
    --admin-text: #F1F5F9;
    --admin-text-secondary: #94A3B8;
    --admin-border: #475569;
    --admin-shadow: 0 8px 32px rgba(0,0,0,0.3);
    --admin-radius: 16px;
    --admin-transition: all 0.25s ease;
}
body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--admin-bg);
    color: var(--admin-text);
    line-height: 1.6;
}
ul { list-style: none; }
button { font-family: inherit; cursor: pointer; }

/* 登录页 */
.login-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: radial-gradient(ellipse at center, #1E293B, #0F172A);
    padding: 20px;
}
.login-box {
    background: var(--admin-surface);
    padding: 48px 40px;
    border-radius: var(--admin-radius);
    width: 400px;
    max-width: 100%;
    box-shadow: var(--admin-shadow);
    border: 1px solid var(--admin-border);
}
.login-box h2 {
    font-size: 28px;
    font-weight: 700;
    text-align: center;
}
.login-box .gold { color: var(--admin-primary); }
.login-box .sub {
    text-align: center;
    color: var(--admin-text-secondary);
    font-size: 14px;
    margin-bottom: 28px;
}
.form-group { margin-bottom: 18px; }
.form-group label {
    display: block;
    font-size: 13px;
    font-weight: 500;
    color: var(--admin-text-secondary);
    margin-bottom: 4px;
}
.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 10px 14px;
    background: var(--admin-bg);
    border: 1px solid var(--admin-border);
    border-radius: 10px;
    color: var(--admin-text);
    font-size: 14px;
    transition: var(--admin-transition);
    font-family: inherit;
}
.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--admin-primary);
    box-shadow: 0 0 0 3px rgba(56,189,248,0.15);
}
.btn-login {
    width: 100%;
    padding: 12px;
    background: var(--admin-primary);
    color: #0F172A;
    border: none;
    border-radius: 10px;
    font-weight: 600;
    font-size: 16px;
    cursor: pointer;
    transition: var(--admin-transition);
}
.btn-login:hover {
    background: var(--admin-accent);
    box-shadow: 0 4px 20px rgba(56,189,248,0.3);
}
.login-tip {
    text-align: center;
    margin-top: 16px;
    font-size: 13px;
    color: var(--admin-text-secondary);
}

/* 后台主布局 */
.admin-container {
    display: flex;
    min-height: 100vh;
}
.sidebar {
    width: 240px;
    background: var(--admin-surface);
    border-right: 1px solid var(--admin-border);
    display: flex;
    flex-direction: column;
    height: 100vh;
    position: sticky;
    top: 0;
    overflow-y: auto;
    flex-shrink: 0;
    z-index: 100;
}
.sidebar-header {
    padding: 24px 20px;
    border-bottom: 1px solid var(--admin-border);
}
.sidebar-header .brand {
    font-size: 22px;
    font-weight: 800;
    color: #fff;
}
.sidebar-header .brand .gold { color: var(--admin-primary); }
.sidebar-header .version {
    font-size: 11px;
    color: var(--admin-text-secondary);
    letter-spacing: 1px;
}
.sidebar-nav {
    flex: 1;
    padding: 12px 0;
}
.sidebar-nav li {
    padding: 10px 20px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 14px;
    color: var(--admin-text-secondary);
    transition: var(--admin-transition);
    border-left: 3px solid transparent;
}
.sidebar-nav li:hover {
    background: rgba(56,189,248,0.06);
    color: #fff;
}
.sidebar-nav li.active {
    background: rgba(56,189,248,0.08);
    border-left-color: var(--admin-primary);
    color: #fff;
}
.sidebar-footer {
    padding: 16px 20px;
    border-top: 1px solid var(--admin-border);
}
.btn-logout {
    width: 100%;
    padding: 8px;
    background: transparent;
    border: 1px solid var(--admin-border);
    color: var(--admin-text-secondary);
    border-radius: 8px;
    cursor: pointer;
    transition: var(--admin-transition);
    font-size: 14px;
}
.btn-logout:hover {
    background: rgba(239,68,68,0.1);
    color: #EF4444;
    border-color: #EF4444;
}
.main-content {
    flex: 1;
    padding: 24px 32px;
    min-width: 0;
}
.admin-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 28px;
    flex-wrap: wrap;
    gap: 16px;
}
.admin-header h2 {
    font-size: 24px;
    font-weight: 700;
}
.admin-user {
    display: flex;
    align-items: center;
    gap: 16px;
    font-size: 14px;
    color: var(--admin-text-secondary);
    flex-wrap: wrap;
}
.admin-user .view-site {
    padding: 6px 18px;
    background: var(--admin-primary);
    color: #0F172A;
    border-radius: 50px;
    font-weight: 500;
    transition: var(--admin-transition);
    white-space: nowrap;
}
.admin-user .view-site:hover {
    background: var(--admin-accent);
}
.content-section {
    display: none;
    animation: fadeIn 0.3s ease;
}
.content-section.active { display: block; }
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(12px); }
    to { opacity: 1; transform: translateY(0); }
}

/* 数据统计卡片 */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(4,1fr);
    gap: 16px;
    margin-bottom: 28px;
}
.stat-card {
    background: var(--admin-surface);
    padding: 20px 24px;
    border-radius: var(--admin-radius);
    border: 1px solid var(--admin-border);
}
.stat-card .label {
    font-size: 13px;
    color: var(--admin-text-secondary);
}
.stat-card .number {
    font-size: 32px;
    font-weight: 700;
    color: var(--admin-primary);
}
.welcome-card {
    background: var(--admin-surface);
    padding: 24px;
    border-radius: var(--admin-radius);
    border: 1px solid var(--admin-border);
}
.welcome-card h3 { font-size: 20px; margin-bottom: 8px; }
.welcome-card p { color: var(--admin-text-secondary); }
.welcome-card .tip {
    background: rgba(56,189,248,0.08);
    padding: 12px 16px;
    border-radius: 10px;
    color: var(--admin-primary);
    margin-top: 12px;
    font-size: 14px;
}

/* 工具栏 */
.toolbar {
    display: flex;
    justify-content: space-between;
    margin-bottom: 16px;
    flex-wrap: wrap;
    gap: 12px;
}
.btn-add {
    padding: 8px 24px;
    background: var(--admin-primary);
    color: #0F172A;
    border: none;
    border-radius: 10px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--admin-transition);
    font-size: 14px;
}
.btn-add:hover {
    background: var(--admin-accent);
}

/* 数据表格 */
.data-table {
    background: var(--admin-surface);
    border-radius: var(--admin-radius);
    border: 1px solid var(--admin-border);
    overflow: hidden;
    overflow-x: auto;
}
.data-table table {
    width: 100%;
    border-collapse: collapse;
    min-width: 600px;
}
.data-table th {
    background: var(--admin-bg);
    padding: 12px 16px;
    text-align: left;
    font-size: 12px;
    font-weight: 600;
    text-transform: uppercase;
    color: var(--admin-text-secondary);
    border-bottom: 1px solid var(--admin-border);
    white-space: nowrap;
}
.data-table td {
    padding: 12px 16px;
    border-bottom: 1px solid var(--admin-border);
    font-size: 14px;
    vertical-align: middle;
}
.data-table tr:last-child td { border-bottom: none; }
.table-img {
    width: 50px;
    height: 40px;
    object-fit: cover;
    border-radius: 6px;
}
.btn-edit, .btn-delete {
    padding: 3px 14px;
    border: none;
    border-radius: 6px;
    font-size: 12px;
    font-weight: 500;
    cursor: pointer;
    transition: var(--admin-transition);
    margin-right: 6px;
    margin-bottom: 4px;
}
.btn-edit {
    background: rgba(56,189,248,0.1);
    color: var(--admin-primary);
}
.btn-edit:hover {
    background: var(--admin-primary);
    color: #0F172A;
}
.btn-delete {
    background: rgba(239,68,68,0.1);
    color: #EF4444;
}
.btn-delete:hover {
    background: #EF4444;
    color: #fff;
}

/* 表单卡片 */
.form-card {
    background: var(--admin-surface);
    padding: 28px;
    border-radius: var(--admin-radius);
    border: 1px solid var(--admin-border);
    max-width: 800px;
}
.form-card h3 {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 20px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--admin-border);
}
.btn-save {
    padding: 10px 32px;
    background: var(--admin-primary);
    color: #0F172A;
    border: none;
    border-radius: 10px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--admin-transition);
    font-size: 14px;
}
.btn-save:hover {
    background: var(--admin-accent);
}
.btn-full { width: 100%; }
.image-preview {
    margin-top: 8px;
    max-width: 180px;
    border-radius: 8px;
    overflow: hidden;
    border: 1px solid var(--admin-border);
}
.image-preview img { width: 100%; display: block; }

/* 弹窗 */
.modal {
    display: none;
    position: fixed;
    top:0;left:0;width:100%;height:100%;
    background: rgba(0,0,0,0.6);
    backdrop-filter: blur(8px);
    z-index:2000;
    align-items: center;
    justify-content: center;
    padding:20px;
}
.modal.show { display: flex; }
.modal-content {
    background: var(--admin-surface);
    border-radius: var(--admin-radius);
    width: 560px;
    max-width:100%;
    max-height:90vh;
    overflow-y:auto;
    animation: modalIn 0.25s ease;
}
@keyframes modalIn {
    from { opacity:0; transform:scale(0.96) translateY(-10px); }
    to { opacity:1; transform:scale(1) translateY(0); }
}
.modal-header {
    padding: 16px 24px;
    border-bottom: 1px solid var(--admin-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: sticky;
    top: 0;
    background: var(--admin-surface);
    z-index: 1;
}
.modal-header h3 { font-size: 18px; font-weight: 600; }
.modal-close {
    font-size: 28px;
    background: none;
    border: none;
    color: var(--admin-text-secondary);
    cursor: pointer;
    transition: var(--admin-transition);
    line-height: 1;
}
.modal-close:hover { transform: rotate(90deg); }
.modal-body { padding: 24px; }
.tip-warn {
    background: rgba(239,68,68,0.06);
    padding: 12px 16px;
    border-radius: 8px;
    color: #EF4444;
    font-size: 13px;
    border-left: 3px solid #EF4444;
    margin-bottom: 16px;
}

/* 侧边栏移动端切换按钮 */
.sidebar-toggle {
    display: none;
    background: var(--admin-surface);
    border: 1px solid var(--admin-border);
    color: var(--admin-text);
    width: 40px;
    height: 40px;
    border-radius: 8px;
    align-items: center;
    justify-content: center;
    font-size: 20px;
}

/* ============================================
   后台响应式断点
   ============================================ */
@media (max-width: 1024px) {
    .stats-grid { grid-template-columns: repeat(2,1fr); }
}

@media (max-width: 768px) {
    .sidebar {
        position: fixed;
        left: -260px;
        top: 0;
        bottom: 0;
        transition: left 0.3s ease;
        box-shadow: var(--admin-shadow);
    }
    .sidebar.mobile-open {
        left: 0;
    }
    .sidebar-overlay {
        display: none;
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: rgba(0,0,0,0.5);
        z-index: 99;
    }
    .sidebar-overlay.show { display: block; }
    
    .main-content { padding: 16px; }
    .sidebar-toggle { display: flex; }
    
    .stats-grid { grid-template-columns: repeat(2,1fr); gap: 12px; }
    .stat-card { padding: 16px; }
    .stat-card .number { font-size: 26px; }
    
    .form-card { padding: 20px; }
    
    .modal { padding: 12px; }
    .modal-body { padding: 16px; }
}

@media (max-width: 576px) {
    .stats-grid { grid-template-columns: 1fr; }
    .admin-header h2 { font-size: 20px; }
    
    .toolbar { flex-direction: column; align-items: stretch; }
    .btn-add { width: 100%; }
    
    .data-table th,
    .data-table td { padding: 10px 12px; font-size: 13px; }
    
    .login-box { padding: 32px 24px; }
    .login-box h2 { font-size: 24px; }
}