/* 全局样式 */
body {
    font-family: "Microsoft YaHei", "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
    color: #333;
}

/* 章节列表样式 */
.chapter-list, .mode-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 10px;
    margin-bottom: 20px;
}

.chapter-list .form-check:first-child {
    grid-column: 1 / -1;
    border-bottom: 1px solid #dee2e6;
    padding-bottom: 10px;
    margin-bottom: 10px;
}

/* 题目卡片样式 */
.question-card {
    margin-bottom: 20px;
    border-radius: 4px;
    overflow: hidden;
}

.question-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 20px;
    background-color: #f1f8ff;
    border-bottom: 1px solid #dee2e6;
}

.question-content {
    padding: 20px;
    font-size: 1.1rem;
}

.options-list {
    list-style-type: none;
    padding-left: 0;
}

.option-item {
    padding: 12px 15px;
    margin-bottom: 10px;
    border: 1px solid #dee2e6;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.2s;
}

.option-item:hover {
    background-color: #f8f9fa;
}

.option-item.selected {
    background-color: #e3f2fd;
    border-color: #90caf9;
}

.option-item.correct {
    background-color: #e8f5e9;
    border-color: #a5d6a7;
}

.option-item.incorrect {
    background-color: #ffebee;
    border-color: #ef9a9a;
}

.answer-section {
    padding: 15px 20px;
    margin-top: 20px;
    background-color: #f8f9fa;
    border-radius: 4px;
    border-left: 4px solid #4caf50;
    display: none;
}

.answer-section.show {
    display: block;
    animation: fadeIn 0.5s;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* 导航按钮样式 */
.navigation-buttons {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 20px;
}

/* 进度条样式 */
.progress {
    height: 8px;
    margin-bottom: 20px;
    border-radius: 4px;
}

/* 背题模式样式 */
.memory-mode .question-content {
    font-weight: bold;
}

.memory-mode .options-list {
    display: none;
}

/* 统计信息样式 */
.stat-item {
    text-align: center;
    padding: 10px;
}

.stat-label {
    display: block;
    font-size: 0.9rem;
    color: #6c757d;
    margin-bottom: 5px;
}

.stat-value {
    font-size: 1.2rem;
    font-weight: bold;
    color: #495057;
}

/* 列表视图样式 */
#question-list {
    max-height: 600px;
    overflow-y: auto;
    scroll-behavior: smooth;
    position: relative;
    padding-bottom: 20px; /* 为加载触发器预留空间 */
}

/* 懒加载相关样式 */
.load-trigger {
    position: relative;
    margin-top: 10px;
    margin-bottom: 10px;
    text-align: center;
}

.load-trigger .spinner-border-sm {
    width: 1rem;
    height: 1rem;
}

/* 全部加载完成提示 */
.text-center.py-3.text-muted {
    font-size: 0.85rem;
    padding: 15px 0;
    border-top: 1px dashed #e9ecef;
    margin-top: 10px;
}

/* 加载动画 */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

#question-list .list-group-item {
    animation: fadeInUp 0.3s ease-out;
    cursor: pointer;
    border-left: 3px solid transparent;
    transition: all 0.2s;
    text-align: left;
    padding: 15px;
}

/* 加载中指示器样式 */
#question-list .text-center.p-3 {
    padding: 20px !important;
    color: #6c757d;
}

#question-list .spinner-border-sm {
    width: 1.5rem;
    height: 1.5rem;
}

/* 列表项淡入效果 */
@media (prefers-reduced-motion: no-preference) {
    #question-list .list-group-item:nth-child(1) { animation-delay: 0.05s; }
    #question-list .list-group-item:nth-child(2) { animation-delay: 0.1s; }
    #question-list .list-group-item:nth-child(3) { animation-delay: 0.15s; }
    #question-list .list-group-item:nth-child(4) { animation-delay: 0.2s; }
    #question-list .list-group-item:nth-child(5) { animation-delay: 0.25s; }
}

#question-list .list-group-item:hover {
    background-color: #f8f9fa;
}

#question-list .list-group-item.active {
    background-color: #e3f2fd;
    border-left-color: #0d6efd;
    color: #212529;
}

#question-list .viewed {
    color: #6c757d;
}

#question-list .list-group-item p {
    margin-bottom: 10px;
    font-size: 0.95rem;
    line-height: 1.4;
}

#question-list .list-group-item small {
    font-size: 0.8rem;
}

#question-list .list-group-item .badge {
    font-size: 0.7rem;
    padding: 0.25em 0.5em;
}

#question-list .bi-check-circle-fill {
    font-size: 1.1rem;
    margin-left: 10px;
}

/* 列表视图中的选项和答案样式 */
.options-list-compact {
    margin-bottom: 10px;
    padding-left: 10px;
    border-left: 2px solid #e9ecef;
}

.option-item-compact {
    font-size: 0.85rem;
    padding: 3px 0;
    color: #495057;
}

.answer-compact {
    border-top: 1px dashed #e9ecef;
    padding-top: 8px;
}

/* 视图切换按钮组样式 */
#view-toggle-container .btn-group {
    border-radius: 4px;
    overflow: hidden;
}

#view-toggle-container .btn {
    padding: 8px 16px;
    font-size: 0.9rem;
}

/* 响应式调整 */
@media (max-width: 768px) {
    .chapter-list, .mode-list {
        grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
        gap: 8px;
    }
    
    .question-header {
        padding: 8px 12px;
        font-size: 0.95rem;
    }
    
    .question-header .badge {
        font-size: 0.75rem;
        padding: 0.2em 0.5em;
    }
    
    .question-content {
        padding: 15px;
        font-size: 1rem;
    }
    
    .options-list {
        margin-top: 10px;
    }
    
    .option-item {
        padding: 10px 12px;
        margin-bottom: 8px;
        font-size: 0.95rem;
    }
    
    .answer-section {
        padding: 12px 15px;
        margin-top: 15px;
        font-size: 0.95rem;
    }
    
    .stat-item {
        padding: 6px;
    }
    
    .stat-label {
        font-size: 0.8rem;
        margin-bottom: 3px;
    }
    
    .stat-value {
        font-size: 1.1rem;
    }
    
    #question-list {
        max-height: 500px;
    }
    
    .navigation-fixed-bottom {
        position: fixed;
        bottom: 0;
        left: 0;
        right: 0;
        display: flex;
        justify-content: space-between;
        align-items: center;
        background-color: #fff;
        padding: 10px 15px;
        box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.1);
        z-index: 1000;
    }
    
    .navigation-fixed-bottom .btn {
        padding: 0.375rem 0.75rem;
        font-size: 0.875rem;
        line-height: 1.5;
        border-radius: 4px;
    }
    
    .navigation-fixed-bottom span {
        font-size: 0.9rem;
        font-weight: 500;
        color: #495057;
    }
    
    body.has-fixed-nav {
        padding-bottom: 60px;
    }
    
    .has-fixed-nav .container > .card:last-of-type {
        margin-bottom: 0;
        border-bottom-left-radius: 0;
        border-bottom-right-radius: 0;
    }
    
    .has-fixed-nav #back-btn {
        font-size: 0.85rem;
        padding: 0.25rem 0.5rem;
    }
    
    .has-fixed-nav #question-container,
    .has-fixed-nav #list-container {
        margin-bottom: 10px;
    }
    
    #list-container {
        margin-bottom: 60px;
    }
    
    .has-fixed-nav .d-flex.justify-content-between.align-items-center.mb-4 .btn {
        font-size: 0.85rem;
        padding: 0.25rem 0.5rem;
    }
    
    .has-fixed-nav #question-counter {
        font-size: 0.85rem;
    }
    
    .has-fixed-nav #back-btn {
        font-size: 0.85rem;
        padding: 0.25rem 0.5rem;
    }
    
    /* 自动下一题开关样式 */
    #auto-next-container {
        margin-left: 10px !important;
    }
    
    #auto-next-container label {
        font-size: 0.85rem;
    }
    
    /* 统计信息更紧凑 */
    .row.text-center.mb-3 {
        margin-bottom: 0.5rem !important;
    }
    
    /* 进度条更小 */
    .progress {
        height: 6px;
        margin-bottom: 12px;
    }
}

@media (max-width: 576px) {
    .chapter-list, .mode-list {
        grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
        gap: 6px;
    }
    
    .navigation-buttons {
        flex-direction: column;
        gap: 10px;
        align-items: stretch;
    }
    
    .navigation-buttons .btn {
        width: 100%;
    }
    
    #question-counter {
        margin-top: 10px;
    }
    
    #question-list .list-group-item p {
        font-size: 0.9rem;
    }
    
    /* 更紧凑的选项 */
    .option-item {
        padding: 8px 10px;
        margin-bottom: 6px;
    }
    
    /* 更紧凑的题目内容 */
    .question-content p {
        margin-bottom: 0.5rem;
    }
    
    /* 提交按钮更小 */
    .submit-btn {
        padding: 0.25rem 0.5rem;
        font-size: 0.875rem;
        margin-top: 0.75rem !important;
    }
}