/* Global styles */
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", "WenQuanYi Micro Hei", sans-serif;
    color: #333;
    background-color: #f7f9fc;
}

/* Heading styles */
h1 {
    color: #2c3e50;
    font-weight: 700;
    margin-bottom: 1rem;
}

h2, h3, h4 {
    color: #3498db;
    font-weight: 600;
}

/* Button styles */
button.primary {
    background: linear-gradient(135deg, #3498db, #2980b9);
    border: none;
    box-shadow: 0 4px 6px rgba(52, 152, 219, 0.3);
}

button.secondary {
    background: #ecf0f1;
    color: #2980b9;
    border: 1px solid #bdc3c7;
}

button:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 8px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
}

/* Input fields enhancement */
input, textarea, select {
    border: 1px solid #ddd;
    border-radius: 8px;
    padding: 10px;
    box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.05);
    transition: all 0.3s ease;
}

input:focus, textarea:focus, select:focus {
    border-color: #3498db;
    box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.25);
}

/* Tab styles */
.tabs {
    border-bottom: 2px solid #e0e0e0;
}

.tab-selected {
    color: #3498db;
    border-bottom: 2px solid #3498db;
}

/* Concept card styles */
.concept-card {
    transition: all 0.3s ease;
    border: 1px solid #e0e0e0;
    border-radius: 12px;
    padding: 16px;
    margin-bottom: 16px;
    cursor: pointer;
    background-color: #fff;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
}

.concept-card:hover {
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    transform: translateY(-3px);
    border-color: #bdc3c7;
}

.selected-card {
    border-color: #3498db;
    background-color: rgba(52, 152, 219, 0.05);
    box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.3);
}

.concept-title {
    font-weight: bold;
    margin-bottom: 8px;
    color: #2c3e50;
    font-size: 1.1em;
}

.concept-desc {
    font-size: 0.95em;
    color: #7f8c8d;
    line-height: 1.5;
}

/* Knowledge graph styles */
#concept-graph {
    background-color: #fff;
    border-radius: 12px;
    padding: 16px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}

#concept-graph img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
}

#concept-graph img:hover {
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

/* Example box styles */
.example-box {
    background-color: #f1f8fe;
    border-left: 4px solid #3498db;
    padding: 15px;
    margin: 15px 0;
    border-radius: 0 8px 8px 0;
}

.example-box h4 {
    margin-top: 0;
    color: #2980b9;
}

/* Resource item styles */
.resource-item {
    padding: 12px;
    margin: 10px 0;
    border-bottom: 1px dashed #e0e0e0;
    transition: all 0.2s ease;
}

.resource-item:hover {
    background-color: #f9f9f9;
}

/* Details and answers styles */
details {
    margin: 10px 0;
    padding: 10px;
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    background-color: #f9f9f9;
}

summary {
    cursor: pointer;
    color: #3498db;
    font-weight: 600;
    padding: 5px;
}

summary:hover {
    color: #2980b9;
}

/* Layout container styles */
.container {
    background-color: #fff;
    border-radius: 12px;
    padding: 20px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    margin-bottom: 20px;
}

/* Responsive adjustments */
@media (max-width: 768px) {
    .concept-card {
        padding: 12px;
    }
    
    .example-box {
        padding: 12px;
    }
}

/* Answer box styles */
.answer-box {
    background-color: #f8f9fa;
    border-radius: 12px;
    padding: 20px;
    margin: 15px 0;
    border: 1px solid #e9ecef;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

.answer-content {
    margin-bottom: 15px;
    line-height: 1.6;
    color: #2c3e50;
}

.answer-content h4 {
    color: #3498db;
    margin-top: 0;
    margin-bottom: 10px;
}

.main-concept {
    background-color: #e3f2fd;
    padding: 10px 15px;
    border-radius: 8px;
    color: #1976d2;
    font-size: 0.95em;
}

.main-concept strong {
    color: #1565c0;
}

/* Answer section styles */
.answer-section {
    margin-top: 20px;
    background: white;
    border-radius: 15px;
    padding: 20px;
}

.answer-box {
    background-color: #f8f9fa;
    border-radius: 12px;
    padding: 20px;
    margin: 15px 0;
    border: 1px solid #e9ecef;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
    transition: all 0.3s ease;
}

.answer-box:hover {
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

.answer-content {
    margin-bottom: 15px;
    line-height: 1.6;
    color: #2c3e50;
    font-size: 1.1em;
}

.main-concept {
    background-color: #e3f2fd;
    padding: 12px 16px;
    border-radius: 8px;
    color: #1976d2;
    font-size: 0.95em;
    margin-top: 15px;
    border: 1px solid rgba(25, 118, 210, 0.1);
}

.main-concept strong {
    color: #1565c0;
    font-weight: 600;
}

/* Loading animation styles */
.loading {
    padding: 20px;
    text-align: center;
    color: #666;
    font-size: 1.1em;
    position: relative;
}

.loading:after {
    content: '...';
    position: absolute;
    animation: dots 1.5s steps(5, end) infinite;
}

@keyframes dots {
    0%, 20% { content: '.'; }
    40% { content: '..'; }
    60% { content: '...'; }
    80%, 100% { content: ''; }
}

.loading::before {
    content: '';
    display: block;
    width: 30px;
    height: 30px;
    border: 3px solid #3498db;
    border-top-color: transparent;
    border-radius: 50%;
    margin: 0 auto 10px;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* 概念详解面板样式 */
.concept-explanation {
    padding: 20px;
    background: white;
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.explanation-content {
    line-height: 1.6;
    margin: 15px 0;
    color: #2c3e50;
}

.examples-section {
    margin-top: 20px;
}

.example-box {
    background: #f8f9fa;
    border-left: 4px solid #3498db;
    padding: 15px;
    margin: 15px 0;
    border-radius: 0 8px 8px 0;
}

.example-problem {
    margin-bottom: 10px;
    color: #2c3e50;
}

.example-solution {
    color: #34495e;
    padding: 10px;
    background: rgba(52, 152, 219, 0.05);
    border-radius: 4px;
}

/* 加载动画样式 */
.loading {
    text-align: center;
    padding: 20px;
}

.loading-spinner {
    border: 3px solid #f3f3f3;
    border-top: 3px solid #3498db;
    border-radius: 50%;
    width: 30px;
    height: 30px;
    animation: spin 1s linear infinite;
    margin: 0 auto 10px;
}

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

.loading-text {
    color: #666;
    font-size: 0.9em;
}

/* 新增的样式 */
.concept-explanation-container {
    margin-top: 20px;
    padding: 15px;
    background: white;
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
    max-height: 600px;  /* 固定最大高度 */
    overflow-y: auto;   /* 添加垂直滚动条 */
    
    /* 自定义滚动条样式 */
    scrollbar-width: thin;
    scrollbar-color: #3498db #f1f1f1;
}

/* Webkit浏览器的滚动条样式 */
.concept-explanation-container::-webkit-scrollbar {
    width: 8px;
}

.concept-explanation-container::-webkit-scrollbar-track {
    background: #f1f1f1;
    border-radius: 4px;
}

.concept-explanation-container::-webkit-scrollbar-thumb {
    background: #3498db;
    border-radius: 4px;
}

.concept-explanation-container::-webkit-scrollbar-thumb:hover {
    background: #2980b9;
}

.concept-explanation-container h3 {
    color: #2c3e50;
    margin-bottom: 15px;
    position: sticky;
    top: 0;
    background: white;
    padding: 10px 0;
    z-index: 1;
}

/* 内容区域样式 */
.card-explanation {
    padding: 20px;
    background: white;
    border-radius: 12px;
}

.explanation-section, .key-points-section, .examples-section, 
.practice-section, .resources-section {
    margin-top: 20px;
    padding: 15px;
    background: #f8f9fa;
    border-radius: 8px;
}

.explanation-section h4, .key-points-section h4, 
.examples-section h4, .practice-section h4, 
.resources-section h4 {
    color: #2c3e50;
    margin-bottom: 10px;
}

/* 修改generate_card_explanation函数中的标题文本 */
.explanation-section h4:before { content: "📚 Concept Explanation"; }
.key-points-section h4:before { content: "🎯 Key Points"; }
.examples-section h4:before { content: "📝 Example Analysis"; }
.practice-section h4:before { content: "✍️ Practice Problems"; }
.resources-section h4:before { content: "📚 Learning Resources"; }

/* 加载动画容器 */
.loading-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 40px;
    background: white;
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

/* 加载动画旋转器 */
.loading-spinner {
    width: 50px;
    height: 50px;
    border: 4px solid #f3f3f3;
    border-top: 4px solid #3498db;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 20px;
}

/* 加载文本 */
.loading-text {
    color: #666;
    font-size: 1.1em;
    margin-top: 10px;
}

/* 旋转动画 */
@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}