/* ============================================================
   超市管理系统 - 全局公共样式表
   采用简洁的CSS排版，适合课堂演示
   ============================================================ */

/* 全局重置与基础样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box; /* 盒模型统一 */
}

body {
    font-family: "Microsoft YaHei", Arial, sans-serif; /* 微软雅黑字体 */
    font-size: 14px;
    color: #333;
    background: #f0f2f5; /* 浅灰色背景 */
    line-height: 1.6;
}

a {
    color: #1890ff;
    text-decoration: none;
}
a:hover {
    color: #40a9ff;
}

/* ============================================================
   登录页面样式
   ============================================================ */
.login-wrap {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh; /* 垂直居中 */
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%); /* 渐变背景 */
}

.login-box {
    background: #fff;
    padding: 40px;
    border-radius: 8px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.15); /* 阴影效果 */
    width: 380px;
}

.login-box h2 {
    text-align: center;
    margin-bottom: 30px;
    color: #333;
    font-size: 24px;
}

.login-box .form-group {
    margin-bottom: 20px;
}

.login-box label {
    display: block;
    margin-bottom: 6px;
    font-weight: bold;
    color: #555;
}

.login-box input[type="text"],
.login-box input[type="password"] {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid #d9d9d9;
    border-radius: 4px;
    font-size: 14px;
    transition: border-color 0.3s; /* 过渡动画 */
}

.login-box input:focus {
    border-color: #1890ff;
    outline: none;
    box-shadow: 0 0 0 2px rgba(24,144,255,0.2);
}

.login-box .btn-login {
    width: 100%;
    padding: 10px;
    background: #1890ff;
    color: #fff;
    border: none;
    border-radius: 4px;
    font-size: 16px;
    cursor: pointer;
    transition: background 0.3s;
}

.login-box .btn-login:hover {
    background: #40a9ff;
}

.login-box .error-msg {
    color: #ff4d4f;
    text-align: center;
    margin-bottom: 15px;
    font-size: 13px;
}

/* ============================================================
   后台管理布局
   ============================================================ */
.layout {
    display: flex;
    min-height: 100vh;
}

/* 左侧导航栏 */
.sidebar {
    width: 220px;
    background: #001529; /* 深色背景 */
    color: #fff;
    flex-shrink: 0; /* 不被压缩 */
}

.sidebar .logo {
    padding: 20px;
    text-align: center;
    font-size: 18px;
    font-weight: bold;
    border-bottom: 1px solid rgba(255,255,255,0.1);
}

.sidebar .menu {
    list-style: none;
    padding: 10px 0;
}

.sidebar .menu li a {
    display: block;
    padding: 12px 24px;
    color: rgba(255,255,255,0.65);
    transition: all 0.3s;
    font-size: 14px;
}

.sidebar .menu li a:hover,
.sidebar .menu li a.active {
    color: #fff;
    background: #1890ff; /* 选中蓝色高亮 */
}

.sidebar .menu li a .icon {
    margin-right: 8px;
}

/* 右侧主内容区 */
.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
}

/* 顶部导航条 */
.topbar {
    height: 56px;
    background: #fff;
    box-shadow: 0 1px 4px rgba(0,0,0,0.08);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 24px;
}

.topbar .user-info {
    color: #666;
}

.topbar .user-info a {
    margin-left: 10px;
    color: #ff4d4f;
}

/* 内容区域 */
.content {
    padding: 24px;
    flex: 1;
}

/* 页面标题 */
.page-title {
    font-size: 20px;
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 2px solid #1890ff;
    color: #333;
}

/* ============================================================
   统计卡片（首页使用）
   ============================================================ */
.stat-cards {
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
    margin-bottom: 24px;
}

.stat-card {
    flex: 1;
    min-width: 200px;
    background: #fff;
    border-radius: 8px;
    padding: 24px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.06);
    text-align: center;
}

.stat-card .num {
    font-size: 36px;
    font-weight: bold;
    color: #1890ff;
}

.stat-card .label {
    color: #999;
    margin-top: 8px;
    font-size: 14px;
}

.stat-card.warning .num { color: #faad14; }
.stat-card.danger .num { color: #ff4d4f; }
.stat-card.success .num { color: #52c41a; }

/* ============================================================
   表格样式
   ============================================================ */
.table-wrap {
    background: #fff;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.06);
    overflow-x: auto; /* 小屏幕横向滚动 */
}

table {
    width: 100%;
    border-collapse: collapse; /* 合并边框 */
}

table th,
table td {
    padding: 12px 16px;
    text-align: left;
    border-bottom: 1px solid #f0f0f0;
    white-space: nowrap;
}

table th {
    background: #fafafa;
    font-weight: bold;
    color: #333;
    font-size: 13px;
}

table tr:hover {
    background: #e6f7ff; /* 鼠标悬停行高亮 */
}

/* ============================================================
   按钮样式
   ============================================================ */
.btn {
    display: inline-block;
    padding: 6px 16px;
    border: 1px solid #d9d9d9;
    border-radius: 4px;
    cursor: pointer;
    font-size: 13px;
    transition: all 0.3s;
    text-align: center;
}

.btn-primary {
    background: #1890ff;
    color: #fff;
    border-color: #1890ff;
}
.btn-primary:hover {
    background: #40a9ff;
    color: #fff;
}

.btn-success {
    background: #52c41a;
    color: #fff;
    border-color: #52c41a;
}
.btn-success:hover {
    background: #73d13d;
    color: #fff;
}

.btn-danger {
    background: #ff4d4f;
    color: #fff;
    border-color: #ff4d4f;
}
.btn-danger:hover {
    background: #ff7875;
    color: #fff;
}

.btn-warning {
    background: #faad14;
    color: #fff;
    border-color: #faad14;
}
.btn-warning:hover {
    background: #ffc53d;
    color: #fff;
}

.btn-sm {
    padding: 3px 10px;
    font-size: 12px;
}

/* ============================================================
   表单样式
   ============================================================ */
.form-box {
    background: #fff;
    border-radius: 8px;
    padding: 24px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.06);
    margin-bottom: 20px;
}

.form-box .form-item {
    margin-bottom: 16px;
    display: flex;
    align-items: center;
}

.form-box .form-item label {
    width: 100px;
    text-align: right;
    margin-right: 12px;
    font-weight: bold;
    color: #555;
    flex-shrink: 0;
}

.form-box .form-item input,
.form-box .form-item select,
.form-box .form-item textarea {
    padding: 8px 12px;
    border: 1px solid #d9d9d9;
    border-radius: 4px;
    font-size: 14px;
    flex: 1;
    max-width: 300px;
}

.form-box .form-item input:focus,
.form-box .form-item select:focus {
    border-color: #1890ff;
    outline: none;
}

/* 搜索栏 */
.search-bar {
    background: #fff;
    padding: 16px 24px;
    border-radius: 8px;
    margin-bottom: 16px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.06);
    display: flex;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
}

.search-bar input,
.search-bar select {
    padding: 6px 12px;
    border: 1px solid #d9d9d9;
    border-radius: 4px;
    font-size: 13px;
}

/* ============================================================
   分页样式
   ============================================================ */
.pagination {
    padding: 16px 24px;
    display: flex;
    align-items: center;
    gap: 6px;
    flex-wrap: wrap;
}

.pagination a {
    display: inline-block;
    padding: 4px 12px;
    border: 1px solid #d9d9d9;
    border-radius: 4px;
    color: #333;
    font-size: 13px;
}

.pagination a:hover {
    border-color: #1890ff;
    color: #1890ff;
}

.pagination .current {
    display: inline-block;
    padding: 4px 12px;
    background: #1890ff;
    color: #fff;
    border-radius: 4px;
    font-size: 13px;
}

.pagination .page-info {
    margin-left: 12px;
    color: #999;
    font-size: 13px;
}

/* ============================================================
   收银台专用样式
   ============================================================ */
.checkout-wrap {
    display: flex;
    gap: 20px;
}

.checkout-left {
    flex: 2;
}

.checkout-right {
    flex: 1;
    min-width: 300px;
}

.cart-table {
    background: #fff;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.06);
    overflow: hidden;
}

.cart-summary {
    background: #fff;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.06);
    padding: 20px;
    position: sticky;
    top: 20px;
}

.cart-summary .total-price {
    font-size: 28px;
    font-weight: bold;
    color: #ff4d4f;
    text-align: center;
    margin: 16px 0;
}

.cart-summary .btn-checkout {
    width: 100%;
    padding: 12px;
    background: #52c41a;
    color: #fff;
    border: none;
    border-radius: 4px;
    font-size: 16px;
    cursor: pointer;
}

.cart-summary .btn-checkout:hover {
    background: #73d13d;
}

/* 状态标签 */
.tag {
    display: inline-block;
    padding: 2px 8px;
    border-radius: 3px;
    font-size: 12px;
}
.tag-green { background: #f6ffed; color: #52c41a; border: 1px solid #b7eb8f; }
.tag-red { background: #fff2f0; color: #ff4d4f; border: 1px solid #ffccc7; }
.tag-blue { background: #e6f7ff; color: #1890ff; border: 1px solid #91d5ff; }
.tag-orange { background: #fff7e6; color: #faad14; border: 1px solid #ffd591; }

/* 提示信息 */
.msg-success { color: #52c41a; }
.msg-error { color: #ff4d4f; }
.msg-warning { color: #faad14; }

/* 空数据提示 */
.empty-data {
    text-align: center;
    padding: 40px;
    color: #999;
    font-size: 16px;
}