/* 全局样式 */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f5f5;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 头部样式 */
header {
    background-color: #fff;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    padding: 20px 0;
    margin-bottom: 30px;
}

header h1 {
    color: #2c3e50;
    margin-bottom: 15px;
    text-align: center;
}

nav ul {
    display: flex;
    justify-content: center;
    list-style: none;
}

nav ul li {
    margin: 0 15px;
}

nav ul li a {
    text-decoration: none;
    color: #555;
    font-weight: 500;
    padding: 5px 10px;
    border-radius: 4px;
    transition: all 0.3s ease;
}

nav ul li a:hover {
    background-color: #f0f0f0;
}

nav ul li a.active {
    background-color: #3498db;
    color: #fff;
}

/* 主要内容区 */
main {
    background-color: #fff;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    padding: 30px;
    margin-bottom: 30px;
}

section {
    margin-bottom: 30px;
}

section h2 {
    color: #2c3e50;
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 1px solid #eee;
}

/* 表单样式 */
.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
}

.form-group input[type="file"],
.form-group select {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 16px;
}

.form-buttons {
    margin-top: 30px;
}

/* 按钮样式 */
.btn {
    display: inline-block;
    padding: 10px 20px;
    border: none;
    border-radius: 4px;
    font-size: 16px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
}

.btn.primary {
    background-color: #3498db;
    color: #fff;
}

.btn.primary:hover {
    background-color: #2980b9;
}

.btn.secondary {
    background-color: #95a5a6;
    color: #fff;
}

.btn.secondary:hover {
    background-color: #7f8c8d;
}

.btn[disabled] {
    background-color: #ccc;
    cursor: not-allowed;
}

/* 加载动画 */
.loader {
    border: 5px solid #f3f3f3;
    border-top: 5px solid #3498db;
    border-radius: 50%;
    width: 50px;
    height: 50px;
    animation: spin 1s linear infinite;
    margin: 0 auto 20px auto;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

#loading {
    text-align: center;
    padding: 30px 0;
}

/* 隐藏元素 */
.hidden {
    display: none;
}

/* 结果展示区域 */
.result-container {
    display: flex;
    gap: 30px;
    margin-top: 20px;
}

.result-image {
    flex: 0 0 40%;
}

.result-image img {
    max-width: 100%;
    border-radius: 4px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
}

.result-details {
    flex: 1;
}

.result-field {
    margin-bottom: 15px;
}

.result-field strong {
    color: #2c3e50;
    display: inline-block;
    margin-right: 5px;
}

/* 难度星级 */
.difficulty-stars {
    display: inline-block;
}

.difficulty-stars::before {
    content: "★★★★★";
    letter-spacing: 3px;
    color: #ddd;
}

.difficulty-stars[data-rating="1"]::before {
    content: "★☆☆☆☆";
}

.difficulty-stars[data-rating="2"]::before {
    content: "★★☆☆☆";
}

.difficulty-stars[data-rating="3"]::before {
    content: "★★★☆☆";
}

.difficulty-stars[data-rating="4"]::before {
    content: "★★★★☆";
}

.difficulty-stars[data-rating="5"]::before {
    content: "★★★★★";
}

.difficulty-stars[data-rating="1"]::before,
.difficulty-stars[data-rating="2"]::before,
.difficulty-stars[data-rating="3"]::before,
.difficulty-stars[data-rating="4"]::before,
.difficulty-stars[data-rating="5"]::before {
    color: #f39c12;
}

/* 标签样式 */
.tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.tag {
    background-color: #e1f5fe;
    color: #0288d1;
    padding: 4px 10px;
    border-radius: 16px;
    font-size: 14px;
}

/* 表格样式 */
table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 20px;
}

table th, table td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid #ddd;
}

table th {
    background-color: #f8f9fa;
    font-weight: 600;
}

table tbody tr:hover {
    background-color: #f1f8ff;
}

/* 错题列表页面 */
.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.filter-controls {
    display: flex;
    gap: 15px;
    margin-bottom: 20px;
}

.search-box {
    flex: 1;
}

.search-box input {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 4px;
}

.filter-options select {
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 4px;
    min-width: 200px;
}

#no-problems, #no-reviews {
    text-align: center;
    padding: 30px 0;
}

/* 错题详情页面 */
.problem-detail-container {
    display: flex;
    gap: 30px;
    margin-bottom: 30px;
}

.problem-image {
    flex: 0 0 40%;
}

.problem-image img {
    max-width: 100%;
    border-radius: 4px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
}

.problem-info {
    flex: 1;
}

.info-item {
    margin-bottom: 10px;
}

.problem-content-section {
    margin-top: 30px;
}

.content-item {
    margin-bottom: 25px;
}

.content-item h3 {
    color: #2c3e50;
    margin-bottom: 10px;
    font-size: 1.2em;
}

.content-body {
    background-color: #f9f9f9;
    padding: 15px;
    border-radius: 4px;
    border-left: 4px solid #3498db;
    white-space: pre-line;
}

/* 回顾详情页面 */
.review-info {
    margin-bottom: 30px;
    background-color: #f8f9fa;
    padding: 15px;
    border-radius: 4px;
}

.analysis-item {
    margin-bottom: 25px;
}

.analysis-item h4 {
    color: #2c3e50;
    margin-bottom: 10px;
}

.analysis-content {
    background-color: #f9f9f9;
    padding: 15px;
    border-radius: 4px;
    border-left: 4px solid #9b59b6;
    white-space: pre-line;
}

.thumbnail-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 20px;
    margin-top: 20px;
}

.problem-thumbnail {
    border: 1px solid #ddd;
    border-radius: 4px;
    overflow: hidden;
    transition: transform 0.3s ease;
}

.problem-thumbnail:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

.problem-thumbnail img {
    width: 100%;
    height: 150px;
    object-fit: cover;
}

.thumbnail-info {
    padding: 10px;
}

.thumbnail-info h4 {
    font-size: 14px;
    margin-bottom: 5px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* 页脚样式 */
footer {
    text-align: center;
    padding: 20px 0;
    color: #7f8c8d;
    font-size: 14px;
    margin-top: 30px;
}

/* 响应式样式 */
@media (max-width: 768px) {
    .result-container,
    .problem-detail-container {
        flex-direction: column;
    }
    
    .result-image,
    .problem-image {
        flex: 0 0 100%;
        margin-bottom: 20px;
    }
    
    .filter-controls {
        flex-direction: column;
        gap: 10px;
    }
}