/* 会员套餐卡片样式 */
        .card-selected {
            border-color: #206bc4 !important;
            box-shadow: 0 0 0 2px rgba(32, 107, 196, 0.25);
        }

        .card-selected .card-body {
            background-color: #f8fafc;
        }

        /* 会员状态徽章样式 */
        .membership-badge {
            top: 80px;
            left: 20px;
            z-index: 1000;
            padding: 8px 16px;
            border-radius: 20px;
            font-size: 14px;
            font-weight: 500;
            box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
            cursor: pointer;
            transition: all 0.3s ease;
        }

        .membership-badge:hover {
            transform: translateY(-2px);
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
        }

        .membership-badge.vip {
            background: linear-gradient(135deg, #8B5CF6, #EC4899);
            color: white;
        }

        .membership-badge.non-vip {
            background: linear-gradient(135deg, #adadad, #adadad);
            color: white;
        }

        /* 支付二维码样式 */
        #qrCodeImage {
            width: 200px;
            height: 200px;
            background-color: white;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 16px;
            color: #666;
        }

        /* 响应式调整 */
        @media (max-width: 768px) {
            .membership-badge {
                top: 80px;
                right: 10px;
                font-size: 12px;
                padding: 6px 12px;
            }

            #qrCodeImage {
                width: 150px;
                height: 150px;
            }
        }
    
    
        .keyword-container {
            display: flex;
            flex-wrap: wrap;
            gap: 8px;
            padding: 12px;
            background: #f8f9fa;
            border-radius: 8px;
            min-height: 100px;
            max-height: 344px;
            overflow-y: auto;
        }

        .keyword-item {
            background: #e9ecef;
            padding: 4px 8px;
            border-radius: 12px;
            font-size: 0.9em;
            border: 1px solid #dee2e6;
            color: #333;
            cursor: pointer;
            user-select: none;
            transition: all 0.2s;
        }

        .keyword-item.active {
            background-color: #00e335;
            border-color: #c3e6cb;
            color: #155724;
        }
    
    
        /* 难度蒙版样式 */
        .difficulty-overlay {
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            display: flex;
            pointer-events: none;
            z-index: 5;
        }

        .difficulty-segment {
            height: 100%;
            transition: width 0.3s ease;
        }

        .difficulty-happy {
            background-color: rgba(40, 167, 69, 0.3);
        }

        .difficulty-maybe {
            background-color: rgba(255, 193, 7, 0.3);
        }

        .difficulty-sad {
            background-color: rgba(220, 53, 69, 0.3);
        }

        .difficulty-text {
            position: absolute;
            font-weight: bold;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%);
            z-index: 6;
            font-weight: bold;
            color: #333;
            font-size: 11px;
            text-shadow: 0 0 2px white;
            pointer-events: none;
        }

        .question-card.with-difficulty {
            position: relative;
        }
    
        /* 做题记录蒙版样式 */
        .record-overlay {
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background-color: rgba(40, 167, 69, 0.4); /* 绿色半透明蒙版 */
            z-index: 5;
            pointer-events: none;
            display: flex;
            align-items: center;
            justify-content: center;
            border-radius: 4px;
        }

        /* .record-overlay::after {
            content: '已做';
            color: white;
            font-weight: bold;
            font-size: 14px;
            text-shadow: 0 1px 2px rgba(0,0,0,0.5);
        } */

        /* 开关选中颜色自定义 */
        #showMyRecordsSwitch:checked {
            background-color: #28a745;
            border-color: #28a745;
        }

        .modal-overlay {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: rgba(0, 0, 0, 0.5);
            z-index: 10000;
            display: none;
            justify-content: center;
            align-items: center;
        }

        .modal-content {
            background: white;
            /* width: 80%; */
            max-width: 800px;
            max-height: 80vh;
            border-radius: 8px;
            display: flex;
            flex-direction: column;
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
        }

        .modal-header {
            padding: 16px 20px;
            border-bottom: 1px solid #eee;
            background: none;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
#task-modal.word-modal-open .modal-header {
    background: rgba(0, 0, 0, 0.45);
    pointer-events: none;
}
#task-modal.word-modal-open .modal-header * {
    visibility: hidden;
}
#task-modal.ai-modal-open .modal-header {
    background: rgba(0, 0, 0, 0.5);
    pointer-events: none;
}
#task-modal.ai-modal-open .modal-header * {
    visibility: hidden;
}
#task-modal.stats-modal-open .modal-header {
    background: rgba(0, 0, 0, 0.55);
    pointer-events: none;
}
#task-modal.stats-modal-open .modal-header * {
    visibility: hidden;
}
#task-modal.sentence-modal-open .modal-header {
    background: rgba(0, 0, 0, 0.55);
    pointer-events: none;
}
#task-modal.sentence-modal-open .modal-header * {
    visibility: hidden;
}
#task-modal.word-popup-open .modal-header {
    background: rgba(0, 0, 0, 0.55);
    pointer-events: none;
}
#task-modal.word-popup-open .modal-header * {
    visibility: hidden;
}

        .modal-title {
            margin: 0;
            font-size: 18px;
            font-weight: bold;
        }

        .modal-close {
            cursor: pointer;
            font-size: 0;
            color: transparent;
            margin-left: 10px;
            width: 28px;
            height: 28px;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            border-radius: 50%;
            background: transparent;
            border: 2px solid #e53935;
            line-height: 1;
            position: relative;
            outline: none;
        }

        .modal-close:focus,
        .modal-close:focus-visible {
            outline: none;
            box-shadow: none;
        }

        .modal-close::before,
        .modal-close::after {
            content: '';
            position: absolute;
            width: 14px;
            height: 2px;
            background: #e53935;
            border-radius: 2px;
        }

        .modal-close::before {
            transform: rotate(45deg);
        }

        .modal-close::after {
            transform: rotate(-45deg);
        }

        .modal-close.modal-close-text {
            font-size: 13px;
            color: #e53935;
            background: #fff;
            width: auto;
            height: auto;
            padding: 4px 10px;
            border-radius: 6px;
            white-space: nowrap;
        }

        .modal-close.modal-close-text::before,
        .modal-close.modal-close-text::after {
            display: none;
        }

        .modal-body {
            padding: 20px;
            /* overflow-y: auto; */
        }

        .task-item {
            border-bottom: 1px solid #f0f0f0;
            padding-bottom: 16px;
            margin-bottom: 16px;
        }

        .task-meta {
            background: #f8f9fa;
            padding: 8px;
            border-radius: 4px;
            font-size: 13px;
            color: #666;
            margin-bottom: 8px;
        }

        .task-content {
            font-size: 14px;
            line-height: 1.6;
        }

        /* Fullpage Styles for Paper Detail */
        .paper-detail-content {
            font-family: "Times New Roman", SimSun, serif;
            font-size: 11pt;
            line-height: 1.6;
            color: #000;
            max-width: 800px; /* Optional: limit width for better readability */
            margin: 0 auto;   /* Center horizontally */
            padding: 20px;    /* Add some padding */
        }

        .paper-detail-content h1 {
            text-align: center;
            font-size: 16pt;
            font-weight: bold;
            margin-bottom: 20pt;
            margin-top: 0;
        }

        .paper-detail-content .part-title {
            text-align: center;
            font-size: 14pt;
            font-weight: bold;
            margin: 20pt 0 15pt 0;
        }

        .paper-detail-content .section-title {
            font-size: 12pt;
            font-weight: bold;
            margin: 15pt 0 10pt 0;
            text-align: left;
        }

        .paper-detail-content .directions {
            font-style: italic;
            margin: 10pt 0;
            text-align: justify;
            font-size: 10.5pt;
        }

        .paper-detail-content .question {
            margin: 12pt 0;
            text-align: justify;
        }

        .paper-detail-content .question-number {
            font-weight: bold;
            margin-right: 5pt;
        }

        .paper-detail-content .options {
            margin: 8pt 0 8pt 20pt;
            line-height: 1.8;
        }

        .paper-detail-content .option {
            margin: 3pt 0;
        }

        .paper-detail-content .passage-text {
            text-align: justify;
            margin: 15pt 0;
            line-height: 1.8;
            text-indent: 2em;
        }

        .paper-detail-content .passage-text p {
            margin: 8pt 0;
            text-indent: 2em;
        }

        .paper-detail-content .time-limit {
            text-align: center;
            font-size: 11pt;
            margin: 5pt 0 15pt 0;
            color: #333;
        }

        .paper-detail-content .context-text {
            font-style: italic;
            margin: 10pt 0;
            color: #555;
            font-size: 10.5pt;
        }

        .paper-detail-content .translation-box {
            margin: 15pt 0;
            padding: 10pt;
            border: 1px solid #333;
            min-height: 150pt;
        }

        .paper-detail-content .listening-script {
            background: #f5f5f5;
            padding: 10pt;
            margin: 10pt 0;
            font-size: 10pt;
            border-left: 3px solid #333;
            display: none;
        }

        .paper-detail-content .reference-essay {
            margin: 15pt 0;
            padding: 10pt;
            background: #fafafa;
            border: 1px solid #ddd;
        }

        .paper-detail-content .word-bank {
            margin: 15pt 0;
            padding: 10pt;
            border: none;
        }

        .paper-detail-content .word-bank-table {
            width: 100%;
            border-collapse: collapse;
            margin: 10pt 0;
        }

        .paper-detail-content .word-bank-table td {
            width: 20%;
            padding: 3pt 5pt;
            font-size: 10.5pt;
        }

        .paper-detail-content .blank {
            display: inline-block;
            min-width: 30pt;
            border-bottom: 1px solid #000;
            margin: 0 2pt;
            text-align: center;
        }

        .paper-detail-content .paragraph-label {
            font-weight: bold;
            margin-right: 5pt;
        }

        .paper-detail-content .matching-item {
            margin: 8pt 0;
            text-align: justify;
            padding-left: 20pt;
            text-indent: -20pt;
        }

        /* Fullscreen Modal Mode */
        .modal-overlay.fullscreen {
            padding: 0 !important;
            align-items: stretch !important;
        }

        .modal-overlay.fullscreen .modal-content {
            width: 100vw;
            height: 100vh;
            max-width: none;
            max-height: none;
            border-radius: 0;
            margin: 0;
            display: flex;
            flex-direction: column;
        }

        .modal-overlay.fullscreen .modal-body {
            flex: 1;
            padding: 0;
            overflow: hidden;
            /* Let iframe handle scroll */
            background: #f5f5f5;
            /* Match tasks.html background if needed */
        }

        @keyframes taskModalScaleUp {
            from {
                opacity: 0;
                transform: scale(0.9);
            }
            to {
                opacity: 1;
                transform: scale(1);
            }
        }

        #task-modal.modal-animate .modal-content {
            animation: taskModalScaleUp 0.35s ease-out;
        }

        /* Center page content if loaded directly */
        .modal-body .page {
            margin: 0 auto;
            max-width: 800px;
            background: white;
            padding: 40px;
            box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
            min-height: 100%;
            display: flex;
            justify-content: center;
            align-items: center;
            background: #f0f0f0;
        }
        /* 题卡上下间距至少 10px */
    .paper-column .question-item {
        padding-bottom: 10px !important;
    }


























        .part-divider {
        /* height: 2px; */
        width: 120%;
        margin-left: -5px;
        background-color: #49566c;
        display: block;
    }
    
    /* 整张试卷悬浮效果 */
    .question-item.paper-hover::after {
        opacity: 1;
        background-color: rgba(33, 150, 243, 0.3); /* 稍微淡一些的蓝色 */
    }
    
    .question-item.highlighted {
        transform: scale(1.02);
        /* box-shadow: 0 4px 12px rgba(33, 150, 243, 0.3); */
    }
    
    .question-overlay {
         position: absolute;
         top: 0;
         left: 0;
         right: 0;
         bottom: 0;
         background-color: rgba(33, 150, 243, 0.3);
         /* border: 2px solid #5a5a5a; */
         border: 2px solid #2196f3;
         border-radius: 4px;
         pointer-events: none;
         z-index: 10;
     }

    .word-overlay {
         position: absolute;
         top: 0;
         left: 0;
         right: 0;
         bottom: 0;
         background-color: rgba(246, 50, 50, 0.3);
         border: 2px solid rgb(255, 160, 160);
         border-radius: 4px;
         pointer-events: none;
         z-index: 10;
     }

    .word-stat-item.word-long-pressed {
        background-color: rgba(246, 50, 50, 0.3) !important;
        border-color: rgb(255, 160, 160) !important;
    }

    .word-stat-item {
        -webkit-touch-callout: none;
        -webkit-user-select: none;
        user-select: none;
    }
     
     .question-item:has(.mood-overlay) .word-overlay {
         background-color: transparent;
     }
     
     .question-item:has(.difficulty-overlay) .word-overlay {
         background-color: transparent;
     }
     
     /* 当显示刷题记录时，不显示question-overlay的背景色，只保留边框 */
     .question-item:has(.mood-overlay) .question-overlay {
         background-color: transparent;
     }
     
     /* 当显示难度蒙版时，不显示question-overlay的背景色，只保留边框 */
     .question-item:has(.difficulty-overlay) .question-overlay {
         background-color: transparent;
     }
     
     /* 题目模态框样式 */
     .question-modal {
         position: fixed;
         top: 0;
         left: 0;
         width: 100%;
         height: 100%;
         z-index: 9999;
         display: none;
         align-items: center;
         justify-content: center;
         padding: 20px;
     }
     
     .question-modal-backdrop {
         position: absolute;
         top: 0;
         left: 0;
         width: 100%;
         height: 100%;
         background-color: rgba(0, 0, 0, 0.5);
         backdrop-filter: blur(5px);
         -webkit-backdrop-filter: blur(5px);
     }
     
     .question-modal-content {
         position: relative;
         background: white;
         border-radius: 8px;
         box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
         max-width: 90%;
         max-height: 90%;
         overflow: hidden;
         z-index: 1;
     }
     
     .question-modal-header {
         display: flex;
         justify-content: space-between;
         align-items: center;
         padding: 15px 20px;
         border-bottom: 1px solid #dee2e6;
         background-color: #f8f9fa;
     }
     
     .question-modal-header .modal-title {
         margin: 0;
         font-size: 1.25rem;
         font-weight: 500;
     }
     
     .question-modal-header .btn-close {
         background: none;
         border: none;
         font-size: 24px;
         cursor: pointer;
         color: #6c757d;
         padding: 0;
         width: 30px;
         height: 30px;
         display: flex;
         align-items: center;
         justify-content: center;
     }
     
     .question-modal-header .btn-close:hover {
         color: #000;
     }
     
     .question-modal-body {
         padding: 20px;
         max-height: 70vh;
         overflow-y: auto;
     }
     
     .question-modal .question-item {
         margin-bottom: 15px;
         border: 1px solid #dee2e6;
         border-radius: 4px;
         overflow: hidden;
     }
     
     .question-modal .question-item img {
          width: 100%;
          height: auto;
          display: block;
      }
      
      /* 动画容器样式 */
      .animation-container {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            z-index: 10000;
            pointer-events: none;
        }
        
        .animation-container .question-item {
            border-radius: 8px;
            overflow: hidden;
            background: white;
        }
        
        /* 试卷动画容器样式 */
        .paper-animation-container {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            z-index: 10000;
            pointer-events: none;
        }
        
        /* 试卷模态框样式 */
        .paper-modal {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background-color: rgba(0, 0, 0, 0.5);
            display: none;
            justify-content: center;
            align-items: center;
            z-index: 9999;
            backdrop-filter: blur(5px);
        }
        
        .paper-modal-backdrop {
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background-color: transparent;
        }
        
        .paper-modal-content {
            position: relative;
            background-color: white;
            border-radius: 12px;
            box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
            max-width: 95vw;
            max-height: 90vh;
            width: 1200px;
            overflow: hidden;
            z-index: 1051;
        }
        
        .paper-modal-header {
            padding: 1rem 1.5rem;
            border-bottom: 1px solid #dee2e6;
            display: flex;
            justify-content: space-between;
            align-items: center;
            background-color: #f8f9fa;
        }
        
        .paper-modal-header .modal-title {
            margin: 0;
            font-size: 1.25rem;
            font-weight: 600;
            color: #495057;
        }
        
        .paper-modal-header .btn-close {
            background: none;
            border: none;
            font-size: 1.5rem;
            cursor: pointer;
            color: #6c757d;
            padding: 0;
            width: 30px;
            height: 30px;
            display: flex;
            align-items: center;
            justify-content: center;
            border-radius: 50%;
            transition: all 0.2s ease;
        }
        
        .paper-modal-header .btn-close:hover {
            background-color: #e9ecef;
            color: #495057;
        }
        
        .paper-modal-body {
            padding: 1.5rem;
            overflow-y: auto;
            max-height: calc(90vh - 80px);
        }
        
        .paper-modal-body .card:not(.question-card) {
            border: none;
            box-shadow: none;
        }
        
        .paper-modal-body .card-header {
            background-color: transparent;
            border-bottom: 1px solid #dee2e6;
            cursor: default !important;
        }
        
        .paper-modal-body .question-item {
            margin-bottom: 1rem;
        }
        
        .paper-modal-body .question-item img {

/* 上传视频模态框样式修复 */
#uploadVideoModal {
    pointer-events: auto !important;
    z-index: 10000 !important;
    background-color: rgba(0, 0, 0, 0.3) !important;
}

#uploadVideoModal .modal-dialog {
    pointer-events: auto !important;
    z-index: 10001 !important;
}

#uploadVideoModal .modal-content {
    pointer-events: auto !important;
    z-index: 10002 !important;
    background-color: white !important;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3) !important;
}

#uploadVideoModal .modal-body {
    pointer-events: auto !important;
}

#uploadVideoModal .form-control {
    pointer-events: auto !important;
    background-color: white !important;
    border: 1px solid #ced4da !important;
}

#uploadVideoModal .btn {
    pointer-events: auto !important;
}

#uploadVideoModal .modal-backdrop {
    background-color: rgba(0, 0, 0, 0.3) !important;
    z-index: 9999 !important;
    pointer-events: none !important;
}

/* 上传解析图片模态框样式修复 */
#uploadAnalysisModal {
    pointer-events: auto !important;
    z-index: 10000 !important;
    background-color: rgba(0, 0, 0, 0.3) !important;
}

#uploadAnalysisModal .modal-dialog {
    pointer-events: auto !important;
    z-index: 10001 !important;
}

#uploadAnalysisModal .modal-content {
    pointer-events: auto !important;
    z-index: 10002 !important;
    background-color: white !important;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3) !important;
}

#uploadAnalysisModal .modal-body {
    pointer-events: auto !important;
}

#uploadAnalysisModal .form-control {
    pointer-events: auto !important;
    background-color: white !important;
    border: 1px solid #ced4da !important;
}

#uploadAnalysisModal .btn {
    pointer-events: auto !important;
}

#uploadAnalysisModal .modal-backdrop {
    background-color: rgba(0, 0, 0, 0.3) !important;
    z-index: 9999 !important;
    pointer-events: none !important;
}

/* 确保Bootstrap生成的backdrop不会阻止点击 */
.modal-backdrop {
    pointer-events: none !important;
}

/* 但是允许模态框本身接收点击事件来关闭 */
#uploadVideoModal.show {
    pointer-events: auto !important;
}

#uploadVideoModal.show .modal-dialog {
    pointer-events: auto !important;
}

#uploadAnalysisModal.show {
    pointer-events: auto !important;
}

#uploadAnalysisModal.show .modal-dialog {
    pointer-events: auto !important;
}
            max-height: 400px;
        }
        
        /* 题目卡片样式 */
        .question-card {
            box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
            transition: transform 0.2s ease, box-shadow 0.2s ease;
        }
        
        .question-card:hover {
            transform: translateY(-2px);
            box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
        }
        
        .question-card .card-footer {
            background-color: #f8f9fa;
            border-top: 1px solid #dee2e6;
        }
        
        .question-card-buttons .btn {
            border: none !important;
            /* padding: 0.4rem 0.6rem; */
            /* font-size: 0.9rem; */
            min-width: auto;
            transition: all 0.2s ease;
            text-decoration: none;
            /* background: none !important; */
        }
        
        /* 题目卡片按钮默认状态为灰色 */
        .question-card-buttons .btn:not(.selected):not(.active) {
            color: #6c757d !important;
        }
        
        .question-card-buttons .btn:not(.selected):not(.active) svg {
            color: #6c757d !important;
        }
        
        /* 保持选中状态的原有颜色 */
        .question-card-buttons .btn.selected,
        .question-card-buttons .btn.active {
            color: inherit;
        }
        
        .question-card-buttons .btn.selected svg,
        .question-card-buttons .btn.active svg {
            color: inherit;
        }
        
        
        .question-card-buttons  .icon {

        width: 30px !important;
        height: 30px !important;
        margin: 0;
        }
        
        .question-card-buttons .btn:hover {
            transform: translateY(-1px);
            opacity: 0.8;
        }
        
        .question-card-buttons .btn:focus {
            box-shadow: none;
        }
        
        .difficulty-text {
            font-weight: 600;
            font-size: 1rem;
        }
        
        .question-card-buttons .badge {
            font-size: 10px;
            min-width: 18px;
            height: 18px;
            line-height: 18px;
            padding: 0;
        }
        
        .question-card-buttons .like-count {
            background-color: #dc3545 !important;
        }
        
        .question-card-buttons .favorite-count {
            background-color: #ffc107 !important;
            color: #000 !important;
        }
        
        .question-image {
            max-height: 500px;
            object-fit: contain;
            background-color: #fff;
        }
    
    /* ==================== 评论功能样式 ==================== */
    
    /* 评论区整体样式 */
    .comment-section {
        /* position: fixed; */
        bottom: 0;
        left: 0;
        right: 0;
        /* background-color: rgba(0, 0, 0, 0.5); */
        z-index: 1050;
        padding: 20px 0;
        max-height: 80vh;
        overflow-y: auto;
    }
    
    .comment-section .card {
        margin: 0 auto;
        max-width: 800px;
        box-shadow: 0 -5px 15px rgba(0, 0, 0, 0.1);
    }
    
    /* 题目卡片底部按钮选中状态 - 统一蓝色风格 */
    .answer-btn.active,
    .video-btn.active,
    .comment-btn.active,
    .analysis-btn.active {
        color: #206bc4 !important;
    }
    
    .answer-btn.active .btn-label,
    .video-btn.active .btn-label,
    .comment-btn.active .btn-label,
    .analysis-btn.active .analysis-label {
        color: #206bc4 !important;
    }
    
    .answer-btn.active .answer-count,
    .video-btn.active .video-count,
    .comment-btn.active .comment-count {
        background-color: #206bc4 !important;
    }
    
    .analysis-btn.active svg {
        color: #206bc4 !important;
    }
    
    /* 评论项样式 */
    .comment-item {
        border-bottom: 1px solid #e9ecef;
        padding-bottom: 1rem;
    }
    
    .comment-item:last-child {
        border-bottom: none;
    }
    
    .comment-content {
        line-height: 1.5;
        word-wrap: break-word;
    }
    
    .comment-actions .btn {
        font-size: 12px;
        padding: 2px 4px;
    }
    
    .comment-actions .btn:hover {
        color: #206bc4 !important;
    }
    
    /* 回复项样式 */
    .reply-item {
        background-color: #f8f9fa;
        border-radius: 6px;
        padding: 8px;
        margin-left: 20px;
    }
    
    .reply-content {
        font-size: 14px;
        line-height: 1.4;
        word-wrap: break-word;
    }
    
    .reply-actions .btn {
        font-size: 11px;
        padding: 1px 3px;
    }
    
    /* 回复输入框样式 */
    .reply-input-container {
        margin-left: 20px;
    }
    
    .reply-input-container .form-control {
        font-size: 14px;
    }
    
    /* 头像样式 */
    .avatar {
        display: flex;
        align-items: center;
        justify-content: center;
        font-weight: 600;
    }
    
    .avatar-sm {
        width: 32px;
        height: 32px;
        font-size: 14px;
    }
    
    .avatar-xs {
        width: 24px;
        height: 24px;
        font-size: 12px;
    }
    
    /* 点赞按钮动画 */
    .like-btn:hover svg {
        transform: scale(1.1);
        transition: transform 0.2s ease;
    }
    
    /* 评论数量徽章 */
    .comment-count {
        min-width: 16px;
        height: 16px;
        line-height: 16px;
        padding: 0 4px;
        font-size: 10px;
    }
    
    /* 评论区滚动条样式 */
    .comment-section::-webkit-scrollbar {
        width: 6px;
    }
    
    .comment-section::-webkit-scrollbar-track {
        background: rgba(0, 0, 0, 0.1);
    }
    
    .comment-section::-webkit-scrollbar-thumb {
        background: rgba(0, 0, 0, 0.3);
        border-radius: 3px;
    }
    
    .comment-section::-webkit-scrollbar-thumb:hover {
        background: rgba(0, 0, 0, 0.5);
    }

    /* 用户答题记录蒙版样式 */
    .mood-overlay {
        position: absolute;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        pointer-events: none;
        z-index: 10;
        transition: opacity 0.3s ease;
    }

    .mood-overlay.happy {
        background-color: rgba(40, 167, 69, 0.3); /* 绿色 - 熟练 #28a745 */
    }

    .mood-overlay.maybe {
        background-color: rgba(255, 193, 7, 0.3); /* 橙色 - 不熟 #ffc107 */
    }

    .mood-overlay.sad {
        background-color: rgba(220, 53, 69, 0.3); /* 红色 - 不会 #dc3545 */
    }

    /* 题号显示样式 */
    .question-number {
        /* position: absolute; */
        top: 1px;
        /* left: -10px; */
        width: 20px;
        height: 20px;
        color: rgb(77, 77, 77);
        border-radius: 50%;
        align-items: center;
        justify-content: center;
        /* font-size: 10px; */
        font-weight: bold;
        z-index: 2;
        pointer-events: none;
    }

    .show-question-numbers .question-number {
        display: flex;
    }

    /* 确保题目卡片有相对定位 */
    .question-card {
        position: relative;
    }

    /* 显示我的记录开关样式 */
    #showMyRecordsSwitch {
        margin-right: 8px;
    }

    .form-switch-2 .form-check-label {
        font-size: 12px;
        color: #909090;
    }

    /* 确保开关水平排列 */
    .card-actions {
        display: flex;
        align-items: center;
        gap: 1rem;
    }

    .card-actions .form-check {
        margin-bottom: 0;
    }

    /* 模态框中不显示题号 */
    .modal .question-number {
        /* display: none !important; */
    }

    /* 知识点统计图表样式 */
    #knowledgeStatsSection {
        animation: fadeIn 0.3s ease-in-out;
    }

    @keyframes fadeIn {
        from {
            opacity: 0;
            transform: translateY(20px);
        }
        to {
            opacity: 1;
            transform: translateY(0);
        }
    }

    .chart-container {
        text-align: center;
        padding: 0;
    }

    .chart-title {
        font-size: 1.1rem;
        font-weight: 600;
        color: var(--tblr-body-color);
        margin-bottom: 1rem;
    }

    .chart-wrapper {
        position: relative;
        height: 375px;
        margin: 0 auto;
        display: flex;
        align-items: center;
        justify-content: center;
    }

    .chart-wrapper canvas {
        max-width: 100%;
        max-height: 100%;
    }

    .chart-description {
        font-size: 0.875rem;
        line-height: 1.4;
    }

    /* 响应式设计 */
    @media (max-width: 768px) {
        .chart-wrapper {
            height: 300px;
        }
        
        .chart-title {
            font-size: 1rem;
        }
        
        .chart-description {
            font-size: 0.8rem;
        }
    }

    /* 纸张效果样式 - 试卷卡片 */
    .paper-column .card {
        background: transparent;
        border: none;
        box-shadow: none;
    }



    .paper-column .card:hover {
        transform: none;
        /* 移除试卷卡片悬浮时的阴影效果 */
    }
    
    /* 取消试卷头部悬浮阴影效果 */
    .paper-column .paper-header:hover ~ .card-body,
    .paper-column .paper-header:hover {
        box-shadow: none !important;
        transform: none !important;
        transition: none !important;
    }

    /* 取消试卷头部悬浮时字体颜色变化 */
    .paper-column .paper-header:hover .card-title {
        color: #fff !important;
        transition: none !important;
    }

    /* 模态框头部按钮样式 */
    .modal-header-buttons {
        display: flex;
        align-items: center;
        gap: 0.5rem;
    }

    .modal-header-buttons .btn {
        display: flex;
        align-items: center;
        gap: 0.25rem;
        white-space: nowrap;
    }

    .modal-header-buttons .btn i {
        font-size: 0.875rem;
    }

    .question-modal-header {
        display: flex;
        justify-content: space-between;
        align-items: center;
        padding: 1rem 1.5rem;
        border-bottom: 1px solid #dee2e6;
    }

    .question-modal-header .modal-title {
        margin: 0;
        font-size: 1.25rem;
        font-weight: 500;
    }

    /* 试卷内容区域的纸张效果 */
    .paper-column .card-header,
    .paper-column .card-body {
        background: #fefefe;
        box-shadow: 
            0.3px 0.5px 0.7px rgba(0, 0, 0, 0.36),
            0.8px 1.6px 2px -0.8px rgba(0, 0, 0, 0.36),
            2.1px 4.1px 5.2px -1.7px rgba(0, 0, 0, 0.36),
            5px 10px 12.6px -2.5px rgba(0, 0, 0, 0.36);
        border-radius: 2px;
        margin: 0 0.3vw 0 0;
        padding: 5px 5px !important;
    }



    /* 桌子纹理背景 */
    /* #mainContent {
        background: linear-gradient(135deg, #D2B48C 0%, #DEB887 25%, #D2B48C 50%, #DEB887 75%, #D2B48C 100%);
        background-size: 40px 40px;
        position: relative;
    } */

    /* #mainContent::before {
        content: '';
        position: absolute;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: 
            repeating-linear-gradient(
                90deg,
                transparent,
                transparent 2px,
                rgba(160, 82, 45, 0.08) 2px,
                rgba(160, 82, 45, 0.08) 4px
            ),
            repeating-linear-gradient(
                0deg,
                transparent,
                transparent 20px,
                rgba(139, 69, 19, 0.1) 20px,
                rgba(139, 69, 19, 0.1) 22px
            );
        pointer-events: none;
        z-index: 0;
    } */

    #mainContent .container-xl {
        position: relative;
        z-index: 1;
    }

    /* 试卷头部样式优化：改为白色粉笔字效果，移除悬浮阴影 */
    .paper-header {
        /* background: rgba(255, 255, 255, 0.95); */
        /* border-bottom: 1px solid rgba(0, 0, 0, 0.1); */
        /* backdrop-filter: blur(2px); */
        margin: 0 !important;
        font-size: 1vw!important;

        color: #fff;
        font-weight: 600;
        letter-spacing: 0.3px;
        font-family: "Chalkboard", "Comic Sans MS", "Segoe UI", -apple-system, system-ui, sans-serif;
        /* 多层次文本阴影，模拟粉笔字的颗粒与发散效果 */
        /* text-shadow:
            0 0 1px rgba(255, 255, 255, 0.9),
            0 0 2px rgba(255, 255, 255, 0.7),
            1px 0 1px rgba(255, 255, 255, 0.3),
            -1px 0 1px rgba(255, 255, 255, 0.3),
            0.5px 1px 0 rgba(255, 255, 255, 0.2); */
        /* 移除原有的阴影与悬浮动效 */
        box-shadow: none !important;
        transition: none !important;
    }

    /* 标题也应用粉笔字效果，确保 hover 不变色 */
    .paper-header .card-title {
        color: #fff !important;
        font-weight: 500;
        font-size: 0.7vw;
        
        /* text-shadow:
            0 0 1px rgba(255, 255, 255, 0.9),
            0 0 2px rgba(255, 255, 255, 0.7),
            1px 0 1px rgba(255, 255, 255, 0.3),
            -1px 0 1px rgba(255, 255, 255, 0.3),
            0.5px 1px 0 rgba(255, 255, 255, 0.25); */
    }

    /* 题目图片样式优化 */
    .question-item img {
        /* box-shadow: 0 1px 3px rgba(0, 0, 0, 0.2); */
        background: white;
    }
    /* 题卡上下间距至少 10px */
    .paper-column .question-item {
        padding-bottom: 10px !important;
    }
.col-md-t {
    width: 4.5vw;
    padding: 0px;
}




        /* Fullscreen modal styles */
        #task-modal {
            /* This is the overlay */
            display: none; /* Controlled by JS */
            position: fixed;
            top: 0;
            left: 0;
            width: 100vw;
            height: 100vh;
            background: rgba(0, 0, 0, 0.5);
            z-index: 10000;
            justify-content: center;
            align-items: center;
            padding: 0 !important;
            margin: 0 !important;
        }

        #task-modal .modal-content {
            border-radius: 20px;
            width: 99vw;
            height: 98vh;
            top:1vh;
            max-width: none;
            max-height: none;
            background: white;
            display: flex;
            flex-direction: column;
            overflow: hidden;
            margin: 0 !important;
            border: none;
        }

        /* Ensure modal body takes available space */
        #task-modal .modal-body {
            flex: 1;
            /* overflow: auto; */
            padding: 0; /* Remove padding if iframe is inside */
        }

        /* When fullscreen class is applied (redundant now but kept for compatibility) */
        /* #task-modal.fullscreen .modal-content { */
            /* width: 100vw; */
            /* height: 100vh; */
            /* max-width: none; */
            /* max-height: none; */
            /* border-radius: 0; */
            /* margin: 0; */
        /* } */

/* Night Mode Styles - Scoped to Task Modal Only */
#task-modal.night-mode .modal-content,
#task-modal.night-mode .modal-body,
#task-modal.night-mode .modal-header,
#task-modal.night-mode .modal-title,
#task-modal.night-mode .modal-close {
    background-color: #000 !important;
    color: #aaa !important;
    border-color: #333 !important;
}

#task-modal.night-mode .modal-close.modal-close-text {
    background-color: #fff !important;
    color: #e53935 !important;
    border-color: #e53935 !important;
}

.modal-title-note {
    font-size: 12px;
    color: #999;
}

#task-modal.night-mode .btn {
    background-color: #000 !important;
    color: #aaa !important;
    border-color: #333 !important;
}

#task-modal.night-mode .btn:hover {
    background-color: #222 !important;
}

#task-modal.night-mode #knowledgeFilterContainer select {
    background-color: #000 !important;
    color: #aaa!important;
    border-color: #333 !important;
}

#task-modal.night-mode #knowledgeFilterContainer option {
    background-color: #000 !important;
    color: #aaa!important;
}

#task-modal #displayModeSelect {
    background-color: #fff;
    color: #333;
    border: 1px solid #ccc;
    border-radius: 6px;
    padding: 2px 8px;
    height: 28px;
}

#task-modal.eye-mode #displayModeSelect {
    background-color: #C7EDCC;
    color: #2e7d32;
    border-color: #9ccaa3;
}

#task-modal.eye-mode #displayModeSelect option {
    background-color: #C7EDCC;
    color: #2e7d32;
}

#task-modal.night-mode #displayModeSelect {
    background-color: #000 !important;
    color: #aaa !important;
    border-color: #333 !important;
}

#task-modal.night-mode #displayModeSelect option {
    background-color: #000 !important;
    color: #fff !important;
}

.task-timer {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 2px 6px;
    border: 1px solid #ddd;
    border-radius: 6px;
    background: #fff;
    color: #333;
    font-family: "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

.task-timer .timer-display {
    font-size: 12px;
    min-width: 46px;
    text-align: center;
}

.task-timer .timer-btn {
    width: 32px;
    height: 22px;
    border: 1px solid #ccc;
    border-radius: 4px;
    background: #f8f8f8;
    color: #333;
    font-size: 12px;
    line-height: 20px;
    padding: 0;
    cursor: pointer;}

.task-timer .timer-btn-toggle {
    position: relative;
    font-size: 0;
}

.task-timer .timer-btn-toggle::before,
.task-timer .timer-btn-toggle::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

.task-timer .timer-btn-toggle::before {
    width: 0;
    height: 0;
    border-style: solid;
    border-width: 5px 0 5px 8px;
    border-color: transparent transparent transparent #333;
}

.task-timer .timer-btn-toggle.is-running::before {
    width: 3px;
    height: 10px;
    background: #333;
    border: none;
    transform: translate(-6px, -50%);
}

.task-timer .timer-btn-toggle.is-running::after {
    width: 3px;
    height: 10px;
    background: #333;
    transform: translate(2px, -50%);
}

#task-modal.night-mode .task-timer {
    background: #000 !important;
    color: #aaa !important;
    border-color: #333 !important;
}

#task-modal.night-mode .task-timer .timer-btn {
    background: #111 !important;
    color: #aaa!important;
    border-color: #333 !important;
}

    /* Vocabulary Book Styles */
    .book_popup_content .group {
        margin-bottom: 20px;
    }
    .book_popup_content .group h5 {
        font-size: 14px;
        color: #999;
        margin-bottom: 10px;
        padding-left: 5px;
        border-left: 3px solid #667eea;
        font-weight: normal;
    }
    .book_popup_content .group-item ul {
        list-style: none;
        padding: 0;
        margin: 0;
        display: flex;
        flex-wrap: wrap;
        gap: 10px;
    }
    .book_popup_content .group-item li {
        position: relative;
        background: rgb(255, 204, 204);
        border: 1px solid rgb(255, 179, 179);
        border-radius: 4px;
        padding: 5px 25px 5px 10px;
        font-size: 14px;
        color: #333;
        transition: all 0.2s;
    }
    .book_popup_content .group-item li:hover {
        background: #fff;
        border-color: #667eea;
        box-shadow: 0 2px 5px rgba(0,0,0,0.05);
    }
    .book_popup_content .group-item li .delete {
        position: absolute;
        right: 5px;
        top: 50%;
        transform: translateY(-50%);
        cursor: pointer;
        color: #adb5bd;
        font-size: 16px;
        line-height: 1;
        display: none;
    }
    .book_popup_content .group-item li:hover .delete {
        display: block;
    }
    .book_popup_content .group-item li .delete:hover {
        color: #dc3545;
    }