:root {
    --bg-color: #f4f7f6;
    --card-bg: #ffffff;
    --text-color: #333333;
    --schedule-bg: #ffffff;
    
    /* 新增：通用变量 */
    --card-border: #e0e0e0;
    --accent-color: #64b5f6;
    --shadow: 0 4px 12px rgba(0,0,0,0.1);
    
    /* 学科颜色 - 浅色模式 */
    --color-chinese: #e57373; /* 红 */
    --color-math: #64b5f6;    /* 蓝 */
    --color-english: #ffb74d; /* 橙 */
    --color-science: #81c784; /* 绿 */
    --color-social: #9575cd;  /* 紫 */
    --color-other: #90a4ae;   /* 灰 */
}

[data-theme="dark"] {
    --bg-color: #1a1a1a;
    --card-bg: #2d2d2d;
    --text-color: #e0e0e0;
    --schedule-bg: #2d2d2d;
    
    /* 新增：深色模式通用变量 */
    --card-border: #444444;
    --accent-color: #90caf9;
    --shadow: 0 4px 12px rgba(0,0,0,0.3);
    
    /* 学科颜色 - 深色模式 */
    --color-chinese: #ef9a9a;
    --color-math: #90caf9;
    --color-english: #ffcc80;
    --color-science: #a5d6a7;
    --color-social: #b39ddb;
    --color-other: #b0bec5;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    margin: 0;
    padding: 0;
    transition: background-color 0.3s, color 0.3s;
    min-height: 100vh;
    /* 移除 overflow: hidden，让其他页面正常滚动 */
}

header {
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    background-color: var(--card-bg);
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    height: 50px;
    box-sizing: border-box;
}

.header-content {
    display: flex;
    justify-content: space-between; /* 两端对齐 */
    align-items: center;
    width: 100%;
}

#date-display {
    display: flex;
    gap: 10px;
    font-weight: 500;
}

/* 
   主页专用容器 
   只有首页使用这个容器
*/
.main-container {
    display: flex;
    gap: 12px;
    padding: 8px 12px;
    height: calc(100vh - 90px);
    box-sizing: border-box;
    overflow: hidden; /* 只在这个容器内禁止滚动 */
}

/* 左侧：学科任务列表 (竖向) */
.tasks-section {
    flex: 3;
    height: 100%;
    overflow: hidden;
    min-height: 0;
    display: flex;
    flex-direction: column;
}

.task-column {
    display: flex;
    flex-direction: column;
    gap: 6px; /* 进一步减小间距 */
    height: 100%;
    min-height: 0; /* 关键：允许flex子项收缩 */
}

.task-card {
    background-color: var(--card-bg);
    border-radius: 20px;
    padding: 0 12px;
    margin: 2px 20px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex: 1;
    min-height: 0; /* 关键：允许收缩 */
    border-left: 10px solid transparent;
    transition: transform 0.2s;
    overflow: hidden; /* 防止内容溢出 */
}

.task-card:hover {
    transform: translateY(-2px);
}

/* 学科配色应用 */
.task-card[data-subject="语文"] { border-left-color: var(--color-chinese); }
.task-card[data-subject="语文"] h3 { color: var(--color-chinese); }

.task-card[data-subject="数学"] { border-left-color: var(--color-math); }
.task-card[data-subject="数学"] h3 { color: var(--color-math); }

.task-card[data-subject="英语"] { border-left-color: var(--color-english); }
.task-card[data-subject="英语"] h3 { color: var(--color-english); }

.task-card[data-subject="科学"] { border-left-color: var(--color-science); }
.task-card[data-subject="科学"] h3 { color: var(--color-science); }

.task-card[data-subject="社会"] { border-left-color: var(--color-social); }
.task-card[data-subject="社会"] h3 { color: var(--color-social); }

.task-card[data-subject="其他"] { border-left-color: var(--color-other); }
.task-card[data-subject="其他"] h3 { color: var(--color-other); }

/* 卡片主体内容 */
.card-main {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    overflow: hidden;
    margin-right: 10px;
    min-width: 0; /* 允许flex子项收缩 */
}

.card-main h3 {
    margin: 0;
    font-size: 1.1rem;
    line-height: 1.2;
}

/* 滚动文字区域 */
.task-scroll-mask {
    width: 100%;
    overflow: hidden;
    position: relative;
    display: flex;
    align-items: center;
}

.task-content-wrapper {
    width: 100%;
    display: flex; /* 确保宽度计算正确 */
}

.task-content {
    font-size: 1.3rem; /* 稍微减小 */
    font-weight: 600;
    white-space: nowrap;
    padding-right: 50px;
}

/* 只有添加了 is-scrolling 类才滚动 */
.task-content.is-scrolling {
    animation: scroll-left 30s linear infinite; /* 速度更慢 */
}

@keyframes scroll-left {
    0% { transform: translateX(0); }
    10% { transform: translateX(0); } /* 停留更久 */
    100% { transform: translateX(-100%); }
}

/* 未交名单区域 */
.missing-section {
    width: 260px; /* 减小宽度 */
    border-left: 1px solid rgba(0,0,0,0.1);
    padding-left: 10px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    overflow: hidden;
    flex-shrink: 0;
}

.missing-section h4 {
    margin: 0 0 4px 0;
    font-size: 0.8rem;
    color: var(--text-color);
    opacity: 0.7;
}

.missing-list {
    font-size: 0.85rem;
    display: flex;
    flex-wrap: nowrap;
    gap: 6px;
    max-height: 100%;
    overflow-x: auto;
    overflow-y: hidden;
    white-space: nowrap;
    -webkit-overflow-scrolling: touch; /* iOS 平滑滚动 */
    scrollbar-width: none; /* Firefox 隐藏滚动条 */
    -ms-overflow-style: none; /* IE/Edge 隐藏滚动条 */
}

.missing-list::-webkit-scrollbar {
    display: none; /* Chrome/Safari 隐藏滚动条 */
}

.missing-list.auto-scroll-container {
    cursor: grab;
}

.missing-list.auto-scroll-container:active {
    cursor: grabbing;
}

.missing-list .scroll-content {
    display: inline-flex;
    gap: 0.5rem;
    padding: 0.25rem 0;
}

/* 无缝滚动的间隔 */
.missing-list .scroll-gap {
    display: inline-block;
    width: 3rem; /* 两组内容之间的间距 */
    flex-shrink: 0;
}

.missing-list .student-name {
    display: inline-block;
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    background: rgba(0, 0, 0, 0.05);
    transition: transform 0.2s, background 0.2s;
    user-select: none;
    -webkit-tap-highlight-color: transparent; /* 移除触屏点击高亮 */
}

.missing-list .student-name:hover {
    background: rgba(0, 0, 0, 0.1);
    transform: scale(1.05);
}

.missing-list .student-name:active {
    transform: scale(0.95);
}

.missing-list .student-name.completed {
    color: #999 !important;
    text-decoration: line-through;
    opacity: 0.7;
}

/* 右侧：课程表 */
.schedule-section {
    flex-shrink: 0; /* 不收缩 */
    background-color: var(--schedule-bg);
    border-radius: 20px;
    padding: 20px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
    display: flex;
    flex-direction: column;
    width: 220px; /* 固定宽度而非 max-width */
    height: 100%;
    box-sizing: border-box;
    overflow: hidden;
}

.schedule-section h2 {
    margin: 0 0 6px 0;
    text-align: center;
    color: var(--color-math);
    font-size: 1.4rem;
    flex-shrink: 0;
}

#schedule-list {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 18px; /* 减小间距 */
    overflow: hidden; /* 不允许滚动，强制收缩 */
    min-height: 0;
}

/* 课程表项样式 */
#schedule-list > div, 
#schedule-list > p {
    padding: 0 6px;
    background-color: rgba(0,0,0,0.04);
    border-radius: 14px;
    text-align: center;
    font-size: 1.25rem; /* 减小字号 */
    font-weight: 600;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0; 
    flex: 1;
    min-height: 0;
    overflow: hidden;
}

/* 4+5 分配：午休分割线优化 */
#schedule-list > *:nth-child(4) {
    margin-bottom: 20px !important; /* 减小午休间距 */
    position: relative;
}

#schedule-list > *:nth-child(4)::after {
    content: "午休";
    position: absolute;
    bottom: -10px;
    left: 15%;
    width: 70%;
    height: 1px;
    border-bottom: 1px dashed var(--color-other);
    font-size: 0.65rem;
    color: var(--text-color);
    opacity: 0.6;
    text-align: center;
    line-height: 0.1;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* =========================================
   登录页面样式 (Login Page)
   ========================================= */
.login-container { 
    max-width: 400px;
    margin: 80px auto;
    padding: 40px;
    background-color: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 12px;
    box-shadow: var(--shadow);
}

.login-container h2 {
    text-align: center;
    color: var(--accent-color);
    margin-bottom: 30px;
    margin-top: 0;
}

.error-message {
    display: none;
    padding: 12px;
    margin-bottom: 20px;
    background: #fee2e2;
    color: #dc2626;
    border-radius: 6px;
    text-align: center;
    font-size: 0.95rem;
}

[data-theme="dark"] .error-message {
    background: #5c2020;
    color: #fca5a5;
}

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

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: var(--text-color);
}

.form-group input {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--card-border);
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.3s;
    box-sizing: border-box;
    background-color: var(--bg-color);
    color: var(--text-color);
}

.form-group input:focus {
    border-color: var(--accent-color);
    outline: none;
}

/* 登录按钮样式 */
.login-container button[type="submit"] {
    width: 100%;
    padding: 14px;
    background-color: var(--accent-color);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: opacity 0.2s, transform 0.1s;
    margin-top: 10px;
}

.login-container button[type="submit"]:hover {
    opacity: 0.85;
}

.login-container button[type="submit"]:active {
    transform: scale(0.98);
}

/* Header logo 样式 */
.logo {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--accent-color);
}

/* Admin link 样式 */
.admin-link {
    color: var(--text-color);
    text-decoration: none;
    padding: 8px 16px;
    border-radius: 6px;
    transition: background-color 0.2s;
}

.admin-link:hover {
    background-color: rgba(0,0,0,0.05);
}

[data-theme="dark"] .admin-link:hover {
    background-color: rgba(255,255,255,0.1);
}

/* Header controls 样式 */
.header-controls {
    display: flex;
    align-items: center;
    gap: 15px;
}

#theme-toggle {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    padding: 5px;
    border-radius: 50%;
    transition: background-color 0.2s;
}

#theme-toggle:hover {
    background-color: rgba(0,0,0,0.05);
}

[data-theme="dark"] #theme-toggle:hover {
    background-color: rgba(255,255,255,0.1);
}

/* =========================================
   管理页面样式 (Admin Page) - 增强通用性
   ========================================= */
/* 即使没有 .admin-container，也能美化管理页面的基本元素 */

/* 标题样式 */
main{
    padding: 20px;
}

main h1, main h2 {
    color: var(--color-math);
    margin-bottom: 20px;
    margin-top: 30px;
}

/* 按钮通用样式 (.btn) */
.btn, button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 10px 20px;
    border-radius: 6px;
    border: none;
    font-size: 1rem;
    cursor: pointer;
    font-weight: 500;
    text-decoration: none;
    transition: opacity 0.2s;
    font-family: inherit;
}

.btn:hover, button:hover {
    opacity: 0.9;
}

/* 按钮颜色变体 */
.btn-primary, button.save-btn { 
    background-color: var(--color-math); 
    color: white; 
}

.btn-danger, button.delete-btn { 
    background-color: var(--color-chinese); 
    color: white; 
}

.btn-secondary { 
    background-color: var(--color-other); 
    color: white; 
}

/* 管理后台输入区域 (TextArea) */
textarea {
    width: 100%;
    min-height: 80px;
    padding: 12px;
    margin-bottom: 15px;
    border: 1px solid #ccc;
    border-radius: 8px;
    font-family: inherit;
    resize: vertical;
    box-sizing: border-box;
    background-color: var(--card-bg);
    color: var(--text-color);
    display: block;
}

textarea:focus {
    border-color: var(--color-math);
    outline: none;
}

/* 管理表格样式 (Table) */
table {
    width: 100%;
    border-collapse: separate;
    border-spacing: 0;
    margin-top: 15px;
    background-color: var(--card-bg);
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

th {
    background-color: rgba(0,0,0,0.05);
    padding: 15px;
    text-align: left;
    font-weight: 600;
    color: var(--text-color);
    border-bottom: 2px solid rgba(0,0,0,0.1);
}

td {
    padding: 12px 15px;
    border-bottom: 1px solid rgba(0,0,0,0.05);
    vertical-align: middle;
    color: var(--text-color);
}

/* 表格内的输入框 */
table input[type="text"] {
    width: 100%;
    padding: 8px;
    border: 1px solid #ddd;
    border-radius: 4px;
    box-sizing: border-box;
    background-color: var(--bg-color);
    color: var(--text-color);
}

/* 表格内的小按钮 */
table button, 
table .btn {
    padding: 6px 12px;
    font-size: 0.9rem;
    margin: 0 2px;
}

/* 针对 .admin-container 的特定优化 (如果存在) */
.admin-container {
    background-color: var(--card-bg);
    padding: 40px;
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.05);
    margin-bottom: 40px;
    height: auto;
    min-height: 500px;
}

.admin-actions {
    margin-top: 20px;
    margin-bottom: 20px;
    display: flex;
    gap: 15px;
    flex-wrap: wrap;
}

/* =========================================
   管理后台 - 折叠面板
   ========================================= */
.admin-tabs {
    display: flex;
    gap: 10px;
    margin-bottom: 30px;
    flex-wrap: wrap;
    border-bottom: 2px solid var(--card-border);
    padding-bottom: 15px;
}

.tab-btn {
    padding: 12px 24px;
    background-color: transparent;
    border: 2px solid var(--card-border);
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-color);
    transition: all 0.2s;
}

.tab-btn:hover {
    background-color: rgba(0,0,0,0.05);
}

.tab-btn.active {
    background-color: var(--accent-color);
    border-color: var(--accent-color);
    color: white;
}

.admin-panel {
    display: none;
}

.admin-panel.active {
    display: block;
    animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* 子区块 */
.sub-section {
    margin-bottom: 30px;
    padding: 20px;
    background-color: rgba(0,0,0,0.02);
    border-radius: 8px;
}

.sub-section h3 {
    margin-top: 0;
    margin-bottom: 15px;
    color: var(--accent-color);
    font-size: 1.2rem;
}

.panel-hint {
    font-size: 0.9rem;
    color: var(--text-color);
    opacity: 0.6;
    margin-bottom: 10px;
}

/* 内联表单 */
.inline-form {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    align-items: center;
    margin-bottom: 15px;
}

.inline-form input,
.inline-form select {
    padding: 10px;
    border: 1px solid var(--card-border);
    border-radius: 6px;
    font-size: 1rem;
    background-color: var(--bg-color);
    color: var(--text-color);
}

.inline-form input[type="color"] {
    width: 50px;
    height: 40px;
    padding: 2px;
    cursor: pointer;
}

/* 筛选行 */
.filter-row {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 15px;
}

.filter-row select {
    padding: 8px 12px;
    border: 1px solid var(--card-border);
    border-radius: 6px;
    background-color: var(--bg-color);
    color: var(--text-color);
}

/* 课程表输入 */
#schedule-inputs {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin-bottom: 20px;
}

.schedule-row {
    display: flex;
    align-items: center;
    gap: 15px;
}

.schedule-row span {
    width: 60px;
    font-weight: 600;
}

.schedule-row input {
    flex: 1;
    padding: 10px;
    border: 1px solid var(--card-border);
    border-radius: 6px;
    background-color: var(--bg-color);
    color: var(--text-color);
}

.schedule-divider {
    text-align: center;
    color: var(--color-other);
    font-size: 0.9rem;
    padding: 10px 0;
}

/* 小按钮 */
.btn-sm {
    padding: 5px 10px !important;
    font-size: 0.85rem !important;
}

/* 多选下拉框 */
select[multiple] {
    width: 100%;
    max-width: 400px;
    padding: 10px;
    border: 1px solid var(--card-border);
    border-radius: 6px;
    background-color: var(--bg-color);
    color: var(--text-color);
    margin-bottom: 10px;
}

/* 用户信息 */
#user-info {
    font-weight: 500;
    margin-right: 15px;
}

/* 学生姓名标签 */
.student-name {
    display: inline-block;
    padding: 2px 6px;
    margin: 2px;
    background-color: rgba(0, 0, 0, 0.05);
    border-radius: 4px;
    font-size: 1.35rem;
    cursor: pointer;
    transition: all 0.2s;
    font-weight: 500;
}

.student-name:hover {
    background-color: rgba(0, 0, 0, 0.1);
    transform: scale(1.05);
}

/* 已补交状态 - 删除线 + 灰色 */
.student-name.completed {
    text-decoration: line-through;
    opacity: 0.6;
    color: #999 !important;  /* 强制覆盖内联颜色 */
    background-color: rgba(0, 0, 0, 0.03);
}

/* 模态框样式 */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.modal-content {
    background: var(--card-bg, #fff);
    padding: 24px;
    border-radius: 12px;
    min-width: 320px;
    max-width: 90%;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2);
}

.modal-content h3 {
    margin-top: 0;
    margin-bottom: 16px;
}

.modal-form {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.modal-form label {
    display: flex;
    align-items: center;
    gap: 8px;
}

.modal-form input[type="text"],
.modal-form select {
    flex: 1;
    padding: 8px;
    border: 1px solid var(--border-color, #ddd);
    border-radius: 4px;
}

.modal-form input[type="color"] {
    width: 50px;
    height: 32px;
    padding: 0;
    border: none;
    cursor: pointer;
}

.modal-actions {
    display: flex;
    gap: 12px;
    margin-top: 20px;
    justify-content: flex-end;
}

/* 颜色圆点 */
.color-dot {
    display: inline-block;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    vertical-align: middle;
    margin-right: 4px;
}

/* 状态标签 */
.status-done {
    color: #28a745;
}

.status-pending {
    color: #dc3545;
}

/* 禁用行样式 */
.disabled-row {
    opacity: 0.5;
    background-color: rgba(0, 0, 0, 0.02);
}

.disabled-row input:disabled {
    background-color: rgba(0, 0, 0, 0.05);
    cursor: not-allowed;
    color: var(--text-color);
    opacity: 0.6;
    border-color: transparent;
}

/* 深色主题下的禁用行 */
[data-theme="dark"] .disabled-row {
    opacity: 0.45;
    background-color: rgba(255, 255, 255, 0.02);
}

[data-theme="dark"] .disabled-row input:disabled {
    background-color: rgba(255, 255, 255, 0.05);
    color: var(--text-color);
    opacity: 0.5;
    border-color: rgba(255, 255, 255, 0.1);
}

/* ==================== 触屏友好的多选列表 ==================== */
.multi-select-section {
    margin-top: 1rem;
    padding: 1rem;
    background: var(--bg-secondary, #f5f5f5);
    border-radius: 8px;
}

.multi-select-actions {
    display: flex;
    gap: 0.5rem;
    align-items: center;
    margin-bottom: 0.75rem;
    flex-wrap: wrap;
}

.selected-count {
    margin-left: auto;
    font-weight: bold;
    color: var(--primary-color, #1976d2);
    padding: 0.25rem 0.75rem;
    background: var(--bg-primary, #fff);
    border-radius: 12px;
    font-size: 0.9rem;
}

/* 学生复选框列表 - 网格布局 */
.checkbox-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
    gap: 0.5rem;
    max-height: 300px;
    overflow-y: auto;
    padding: 0.5rem;
    background: var(--bg-primary, #fff);
    border-radius: 8px;
    border: 1px solid var(--border-color, #e0e0e0);
    margin-bottom: 1rem;
}

.checkbox-item {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0.6rem 0.5rem;
    background: var(--bg-secondary, #f5f5f5);
    border: 2px solid transparent;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s ease;
    user-select: none;
    text-align: center;
    font-size: 0.9rem;
    min-height: 44px; /* 触屏友好的最小点击区域 */
}

.checkbox-item:hover {
    background: var(--bg-hover, #e3f2fd);
    border-color: var(--primary-color, #1976d2);
}

.checkbox-item:active {
    transform: scale(0.98);
}

.checkbox-item.selected {
    background: var(--primary-color, #1976d2);
    color: #fff;
    border-color: var(--primary-dark, #1565c0);
    font-weight: 500;
}

.checkbox-item.selected::before {
    content: '✓ ';
    font-weight: bold;
}

.checkbox-item .student-info {
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* 暗色主题适配 */
[data-theme="dark"] .checkbox-list {
    background: var(--bg-secondary, #2d2d2d);
    border-color: var(--border-color, #444);
}

[data-theme="dark"] .checkbox-item {
    background: var(--bg-tertiary, #3d3d3d);
}

[data-theme="dark"] .checkbox-item:hover {
    background: var(--bg-hover, #4d4d4d);
}

[data-theme="dark"] .checkbox-item.selected {
    background: var(--primary-color, #64b5f6);
    color: #1a1a1a;
}

/* 批量操作区域 */
.batch-actions {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    padding: 0.75rem;
    background: var(--bg-secondary, #f5f5f5);
    border-radius: 8px;
    margin-bottom: 1rem;
}

.batch-select-actions,
.batch-operation-actions {
    display: flex;
    gap: 0.5rem;
    align-items: center;
    flex-wrap: wrap;
}

.batch-operation-actions {
    padding-top: 0.5rem;
    border-top: 1px solid var(--border-color, #e0e0e0);
}

/* ==================== 历史统计面板样式 ==================== */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.stat-card {
    background: var(--bg-color);
    border: 1px solid var(--card-border);
    border-radius: 12px;
    padding: 1.5rem;
    text-align: center;
    transition: transform 0.2s, box-shadow 0.2s;
}

.stat-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.stat-value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--accent-color);
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 0.9rem;
    color: var(--text-color);
    opacity: 0.7;
}

/* 排行榜样式 */
.ranking-list {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
}

.ranking-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: var(--bg-color);
    border: 1px solid var(--card-border);
    border-radius: 20px;
    font-size: 0.9rem;
}

.ranking-position {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    font-weight: 700;
    font-size: 0.8rem;
}

.ranking-position.top-1 { background: #ffd700; color: #333; }
.ranking-position.top-2 { background: #c0c0c0; color: #333; }
.ranking-position.top-3 { background: #cd7f32; color: #fff; }
.ranking-position.normal { background: var(--color-other); color: #fff; }

.ranking-name {
    font-weight: 500;
}

.ranking-count {
    color: var(--color-chinese);
    font-weight: 600;
}

/* 分页样式 */
.pagination {
    display: flex;
    justify-content: center;
    gap: 0.5rem;
    margin-top: 1rem;
    flex-wrap: wrap;
}

.pagination button {
    min-width: 40px;
    height: 40px;
    padding: 0 12px;
    border: 1px solid var(--card-border);
    background: var(--card-bg);
    color: var(--text-color);
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.2s;
}

.pagination button:hover {
    background: var(--accent-color);
    color: white;
    border-color: var(--accent-color);
}

.pagination button.active {
    background: var(--accent-color);
    color: white;
    border-color: var(--accent-color);
}

.pagination button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* 成功按钮样式 */
.btn-success {
    background-color: var(--color-science) !important;
    color: white !important;
}

/* 警告按钮样式 */
.btn-warning {
    background-color: var(--color-english) !important;
    color: #333 !important;
}

/* 响应式 */
@media (max-width: 768px) {
    body {
        overflow: auto; /* 移动端允许滚动 */
    }
    
    .main-container {
        flex-direction: column;
        height: auto;
        overflow: auto;
    }
    
    .schedule-section {
        width: 100%;
    }
    
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .stat-value {
        font-size: 1.5rem;
    }
}

/* ==================== 富文本编辑器样式 ==================== */
.richtext-modal-content {
    width: 90%;
    max-width: 700px;
    max-height: 90vh;
    overflow-y: auto;
}

.richtext-toolbar {
    display: flex;
    flex-wrap: wrap;
    gap: 4px;
    padding: 10px;
    background: var(--bg-color);
    border: 1px solid var(--card-border);
    border-radius: 8px 8px 0 0;
    align-items: center;
}

.toolbar-btn {
    width: 36px;
    height: 36px;
    padding: 0 !important;
    border: 1px solid var(--card-border) !important;
    background: var(--card-bg) !important;
    color: var(--text-color) !important;
    border-radius: 4px !important;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1rem;
    transition: all 0.2s;
}

.toolbar-btn:hover {
    background: var(--accent-color) !important;
    color: white !important;
    border-color: var(--accent-color) !important;
}

.toolbar-btn.active {
    background: var(--accent-color) !important;
    color: white !important;
}

.toolbar-divider {
    width: 1px;
    height: 24px;
    background: var(--card-border);
    margin: 0 6px;
}

.toolbar-select {
    height: 36px;
    padding: 0 8px;
    border: 1px solid var(--card-border);
    border-radius: 4px;
    background: var(--card-bg);
    color: var(--text-color);
    font-size: 0.9rem;
    cursor: pointer;
}

.toolbar-color-label {
    position: relative;
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--card-border);
    border-radius: 4px;
    background: var(--card-bg);
    cursor: pointer;
    overflow: hidden;
}

.toolbar-color-label input[type="color"] {
    position: absolute;
    width: 100%;
    height: 100%;
    opacity: 0;
    cursor: pointer;
}

.toolbar-color-label .color-icon {
    font-weight: bold;
    font-size: 1rem;
    color: var(--text-color);
    pointer-events: none;
}

.toolbar-color-label .bg-icon {
    background: linear-gradient(to bottom, transparent 60%, #ffff00 60%);
    padding: 0 4px;
}

.richtext-editor {
    min-height: 200px;
    max-height: 300px;
    overflow-y: auto;
    padding: 15px;
    border: 1px solid var(--card-border);
    border-top: none;
    border-radius: 0 0 8px 8px;
    background: var(--card-bg);
    color: var(--text-color);
    font-size: 1.1rem;
    line-height: 1.6;
    outline: none;
}

.richtext-editor:focus {
    box-shadow: inset 0 0 0 2px var(--accent-color);
}

.richtext-editor:empty::before {
    content: "在此输入作业内容...";
    color: var(--text-color);
    opacity: 0.4;
}

.richtext-preview-section {
    margin-top: 15px;
}

.richtext-preview {
    padding: 15px;
    background: var(--bg-color);
    border: 1px dashed var(--card-border);
    border-radius: 8px;
    min-height: 50px;
    font-size: 1.1rem;
    line-height: 1.6;
}

.richtext-preview:empty::before {
    content: "预览区域";
    color: var(--text-color);
    opacity: 0.4;
}

/* 作业内容显示区域 - 支持富文本 */
.task-content-display {
    cursor: pointer;
    padding: 8px 12px;
    border: 1px dashed transparent;
    border-radius: 6px;
    min-height: 40px;
    display: flex;
    align-items: center;
    transition: all 0.2s;
    flex: 1;
}

.task-content-display:hover {
    border-color: var(--accent-color);
    background: rgba(100, 181, 246, 0.05);
}

.task-content-display:empty::before {
    content: "点击编辑作业内容...";
    color: var(--text-color);
    opacity: 0.4;
    font-style: italic;
}

/* 编辑按钮 */
.edit-task-btn {
    width: 36px !important;
    height: 36px !important;
    min-width: 36px !important;
    padding: 0 !important;
    margin-left: 8px;
    flex-shrink: 0;
}

/* 表格单元格内的作业内容包装器 */
.task-content-wrapper-cell {
    display: flex;
    align-items: center;
    gap: 8px;
    width: 100%;
}

.task-content-wrapper-cell .task-content-display {
    flex: 1;
    min-height: 40px;
    padding: 8px 12px;
    border: 1px dashed transparent;
    border-radius: 6px;
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    line-height: 1.5;
    transition: all 0.2s;
}

.task-content-wrapper-cell .task-content-display.editable {
    cursor: pointer;
}

.task-content-wrapper-cell .task-content-display.editable:hover {
    border-color: var(--accent-color);
    background: rgba(100, 181, 246, 0.05);
}

.task-content-wrapper-cell .task-content-display:empty::before {
    content: "点击编辑作业内容...";
    color: var(--text-color);
    opacity: 0.4;
    font-style: italic;
}

/* 暗色主题适配 */
[data-theme="dark"] .richtext-editor {
    background: var(--bg-color);
}

[data-theme="dark"] .toolbar-color-label .bg-icon {
    background: linear-gradient(to bottom, transparent 60%, #666600 60%);
}

[data-theme="dark"] .task-content-wrapper-cell .task-content-display.editable:hover {
    background: rgba(100, 181, 246, 0.1);
}