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

:root {
    /* 颜色变量 */
    --primary-color: #165DFF;
    --primary-dark: #0E42C4;
    --primary-light: #4080FF;
    --secondary-color: #6B7280;
    --background-color: #F9FAFB;
    --card-background: #FFFFFF;
    --text-primary: #1F2937;
    --text-secondary: #6B7280;
    --border-color: #E5E7EB;
    --shadow-light: 0 2px 4px rgba(0, 0, 0, 0.1);
    --shadow-medium: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-hover: 0 10px 15px rgba(0, 0, 0, 0.1);
    --border-radius: 12px;
    --transition: all 0.3s ease;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--background-color);
    color: var(--text-primary);
    line-height: 1.6;
}

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

/* 导航栏样式 */
header {
    background-color: #1a365d;
    color: white;
    box-shadow: var(--shadow-light);
    /*position: sticky;*/
    top: 0;
    z-index: 100;
}

.navbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 20px 0;
    flex-wrap: wrap;
    gap: 15px;
}

.logo h1 {
    font-size: 1.8rem;
    font-weight: 700;
}

.logo h1 a {
    color: white;
    text-decoration: none;
}

.nav-links {
    display: flex;
    gap: 25px;
}

.nav-links a {
    color: white;
    text-decoration: none;
    font-size: 1rem;
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

.nav-links a:hover,
.nav-links a.active {
    color: white;
}

.nav-links a.active::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 100%;
    height: 2px;
    background-color: #63b3ed;
    border-radius: 2px;
}

.search-container {
    display: flex;
    align-items: center;
    background-color: var(--background-color);
    border-radius: 8px;
    padding: 8px 15px;
    border: 1px solid var(--border-color);
    transition: var(--transition);
}

.search-container:focus-within {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(22, 93, 255, 0.1);
}

#search-input {
    border: none;
    background: transparent;
    outline: none;
    padding: 5px;
    font-size: 1rem;
    width: 200px;
}

#search-btn {
    background: none;
    border: none;
    color: var(--secondary-color);
    cursor: pointer;
    font-size: 1.1rem;
    transition: var(--transition);
}

#search-btn:hover {
    color: var(--primary-color);
}

/* 主内容区样式 */
main {
    padding: 40px 0;
}

section {
    margin-bottom: 20px;
}

section {
    margin-bottom: 20px;
    padding-top: 20px;
}

section h2 {
    margin-bottom: 25px;
    color: var(--text-primary);
    font-size: 1.8rem;
    font-weight: 700;
    position: relative;
    padding-left: 15px;
}

section h2::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 5px;
    height: 70%;
    background-color: var(--primary-color);
    border-radius: 5px;
}

/* 卡片通用样式 */
.card {
    background-color: var(--card-background);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-medium);
    padding: 30px;
    transition: var(--transition);
}

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

/* 随机谜语板块 */
.random-section .card {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.riddle-content p {
    font-size: 1.25rem;
    line-height: 1.8;
    margin-bottom: 25px;
}

.answer-container {
    margin-bottom: 30px;
}

#random-answer {
    font-size: 0.9rem;
    color: var(--primary-color);
    font-weight: 500;
    padding: 10px 15px;
    background-color: rgba(22, 93, 255, 0.05);
    border-radius: 6px;
    border: 1px solid rgba(22, 93, 255, 0.2);
}

#random-answer.hidden {
    display: none;
}

.action-buttons {
    display: flex;
    gap: 15px;
    justify-content: center;
    flex-wrap: wrap;
}

/* 按钮样式 */
.btn-primary,
.btn-secondary {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 8px;
}

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

.btn-primary:hover {
    background-color: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(22, 93, 255, 0.3);
}

.btn-secondary {
    background-color: var(--card-background);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover {
    background-color: var(--background-color);
    border-color: var(--primary-light);
    transform: translateY(-2px);
}

/* 热门谜语网格 */
.riddles-grid {
    display: grid;
    grid-template-columns: 1fr; /* 默认单列布局 */
    gap: 25px;
}

/* 三列网格布局 */
.riddles-grid.grid-view {
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
}

/* 布局切换控制区域 */
.layout-controls {
    display: flex;
    justify-content: flex-end;
    margin-bottom: 20px;
    gap: 10px;
}

.layout-btn {
    background-color: var(--card-background);
    border: 1px solid var(--border-color);
    padding: 8px 16px;
    border-radius: 6px;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 6px;
    color: var(--text-secondary);
}

.layout-btn:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.layout-btn.active {
    background-color: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.riddle-card {
    background-color: var(--card-background);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-medium);
    padding: 25px;
    transition: var(--transition);
}

.riddle-card:hover {
    box-shadow: var(--shadow-hover);
    transform: translateY(-3px);
}

.riddle-card h3 {
    font-size: 1.2rem;
    margin-bottom: 15px;
    color: var(--text-primary);
    line-height: 1.5;
}

.riddle-card .answer {    background-color: #f7fafc;    padding: 16px;    border-radius: 8px;    border-left: 3px solid #63b3ed;    opacity: 0;    max-height: 0;    overflow: hidden;    transition: all 0.3s ease;    margin-top: 15px;}

.riddle-card .answer.show {    opacity: 1;    max-height: 150px;}

.riddle-card .answer-content {    font-size: 16px;    color: #2d3748;    font-weight: 600;}

.riddle-card .show-answer-btn {
    background-color: transparent;
    border: 1px solid var(--primary-color);
    color: var(--primary-color);
    padding: 8px 16px;
    border-radius: 6px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: var(--transition);
    margin-top: 15px;
}

.riddle-card .show-answer-btn:hover {
    background-color: var(--primary-color);
    color: white;
}

.riddle-card .meta-info {
    margin-top: 15px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.riddle-card .category-tag {
    background-color: rgba(22, 93, 255, 0.1);
    color: var(--primary-color);
    padding: 4px 10px;
    border-radius: 20px;
    font-size: 0.8rem;
}

/* 分类板块样式 */
.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 20px;
}

.category-card {
    background-color: var(--card-background);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-medium);
    padding: 30px 20px;
    text-align: center;
    text-decoration: none;
    color: var(--text-primary);
    transition: var(--transition);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 15px;
}

.category-card:hover {
    background-color: var(--primary-color);
    color: white;
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

.category-card i {
    font-size: 2.5rem;
    color: var(--primary-color);
    transition: var(--transition);
}

.category-card:hover i {
    color: white;
    transform: scale(1.1);
}

.category-card span {
    font-size: 1.1rem;
    font-weight: 500;
}

/* 分类页面样式 */
.category-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
    flex-wrap: wrap;
    gap: 15px;
    padding-top: 60px;
}

.category-header h2 {
    margin: 0;
    padding: 0;
}

.category-header h2::before {
    display: none;
}

.category-filter {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.filter-btn {
    padding: 8px 16px;
    border: 1px solid var(--border-color);
    background-color: var(--card-background);
    color: var(--text-primary);
    border-radius: 20px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: var(--transition);
}

.filter-btn:hover,
.filter-btn.active {
    background-color: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

/* 页脚样式 */
footer {
    background-color: #2d3748;
    padding: 30px 0;
    border-top: 1px solid var(--border-color);
    margin-top: 50px;
}

footer p {
    text-align: center;
    color: white;
    font-size: 0.9rem;
}

/* 加载和错误状态样式 */
.loading {
    text-align: center;
    padding: 2rem;
    color: #666;
    font-style: italic;
}

.error-message {
    background-color: #fee;
    border: 1px solid #fcc;
    color: #c33;
    padding: 1rem;
    border-radius: 4px;
    text-align: center;
    margin: 1rem 0;
}

/* 搜索按钮加载动画 */
#search-btn:disabled {
    opacity: 0.7;
    cursor: not-allowed;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .navbar {
        flex-direction: row;
        align-items: center;
        justify-content: space-between;
        flex-wrap: wrap;
        gap: 15px;
    }
    
    .logo {
        flex-shrink: 0;
    }
    
    .nav-links {
        flex-shrink: 0;
        display: flex;
        gap: 15px;
    }
    
    .search-container {
        width: 100%;
        order: 3;
    }
    
    #search-input {
        width: 100%;
    }
    
    .riddles-grid {
        grid-template-columns: 1fr !important;
    }
    
    /* 隐藏布局控制按钮 */
    .layout-controls {
        display: none;
    }
    
    /* 确保移动设备上总是使用单列布局 */
    .riddles-grid.grid-view {
        grid-template-columns: 1fr !important;
    }
    
    .categories-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .action-buttons {
        flex-direction: column;
    }
    
    .btn-primary,
    .btn-secondary {
        width: 100%;
        justify-content: center;
    }
    
    .category-header {
        flex-direction: column;
        align-items: flex-start;
    }
}

@media (max-width: 480px) {
    section h2 {
        font-size: 1.5rem;
    }
    
    .card {
        padding: 20px;
    }
    
    .riddle-content p {
        font-size: 1.1rem;
    }
    
    /* 确保在最小屏幕上也是单列布局 */
    .riddles-grid,
    .riddles-grid.grid-view {
        grid-template-columns: 1fr !important;
    }
    
    .categories-grid {
        grid-template-columns: 1fr;
    }
    
    .category-card {
        padding: 25px 15px;
    }
    
    .category-card i {
        font-size: 2rem;
    }
}

/* 加载动画 */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    animation: fadeIn 0.5s ease-out;
}

/* 搜索结果样式 */
.search-results {
    margin-top: 40px;
}

.search-results h2 {
    display: flex;
    align-items: center;
    gap: 10px;
}

.search-results h2::before {
    display: none;
}

.no-results {
    text-align: center;
    padding: 60px 20px;
    color: var(--text-secondary);
}

.no-results i {
    font-size: 3rem;
    margin-bottom: 15px;
    color: var(--secondary-color);
}

/* 加载更多按钮样式 */
.load-more-container {
    text-align: center;
    padding: 30px 0 20px;
    margin-top: 20px;
}

.load-more-btn {
    background-color: #1e3a8a;
    color: white;
    border: none;
    border-radius: 8px;
    padding: 12px 24px;
    font-size: 16px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 500;
    display: block;
    margin: 0 auto;
    text-align: center;
}

.load-more-btn:hover:not(:disabled) {
    background-color: #1e40af;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(30, 58, 138, 0.3);
}

.load-more-btn:active:not(:disabled) {
    transform: translateY(0);
}

.load-more-btn:disabled {
    background-color: #94a3b8;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

/* 没有更多内容提示 */
.no-more-text {
    text-align: center;
    color: #94a3b8;
    font-size: 14px;
    margin: 0;
    padding: 10px;
}