/* ==========================================================================
   1. ROOT VARIABLES & GLOBAL RESET
   ========================================================================== */
:root {
    /* Primary & Accents */
    --primary-color: #0067c6;       /* Microsoft Blue */
    --primary-color-hover: #005da6; /* Darker Blue */
    --secondary-color: #6c757d;

    /* Backgrounds */
    --bg-color: #f2f2f2;
    --panel-bg-color: #ffffff;
    --header-bg-color: #ffffff;
    --title-highlight-bg: rgba(0, 103, 198, 0.07);
    --card-header-bg: rgba(0, 103, 198, 0.1);

    /* Typography */
    --font-color: #333333;
    --font-color-light: #555555;

    /* Borders & Shadows */
    --border-color: #e0e0e0;
    --shadow-sm: 0 2px 4px rgba(0,0,0,0.06);
    --shadow-md: 0 5px 12px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 30px rgba(0,0,0,0.12);

    /* Status Colors */
    --status-red: #d83b01;
    --status-yellow: #ffb900;
    --status-green: #107c10;
    --status-red-bg: #fde7e9;
    --status-yellow-bg: #fff4ce;
    --status-green-bg: #dff6dd;
    --status-gray-bg: #f5f5f5;
    --status-blue-bg: #e3f2fd;
    --status-light-red-bg: #ffebee;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--font-color);
    margin: 0;
    display: flex;
    flex-direction: column;
    height: 100vh;
    overflow: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Custom Scrollbar */
::-webkit-scrollbar { width: 4px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: #0067c6; border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: #ffb900; }

/* Global Interactions */
.clickable-cell { cursor: pointer; }
.clickable-cell:hover {
    filter: brightness(0.95);
    box-shadow: inset 0 0 0 2px var(--primary-color);
}
.clickable-name {
    cursor: pointer; font-weight: 600; color: var(--primary-color);
    text-decoration: underline; text-underline-offset: 3px; text-decoration-color: rgba(0, 103, 198, 0.3);
}
.clickable-name:hover { color: var(--primary-color-hover); text-decoration-color: var(--primary-color); }

/* ==========================================================================
   2. LAYOUT STRUCTURE (Page, Header, Panels)
   ========================================================================== */
/* Header */
.platform-header {
    display: flex; justify-content: space-between; align-items: center;
    padding: 0.75rem 1.5rem; margin-bottom: 1.5rem;
    background: linear-gradient(90deg, var(--primary-color) 0%, #0078d4 100%);
    color: white; box-shadow: var(--shadow-md); flex-shrink: 0;
}
.header-main-content { display: flex; align-items: center; gap: 1.5rem; }
.header-title-group { display: flex; align-items: center; gap: 0.75rem; }
.header-title-group .fas { font-size: 2rem; color: white; text-shadow: 0 2px 4px rgba(0,0,0,0.2); }
.header-title-wrapper { display: flex; flex-direction: column; justify-content: center; line-height: 1.1; }
.platform-header h1 {
    font-size: 1.65rem; font-weight: 600; color: white; margin: 0 0 2px 0;
    text-shadow: 0 2px 4px rgba(0,0,0,0.2);
}
.current-user-text {
    font-size: 0.85rem; font-weight: 400; opacity: 0.85;
    letter-spacing: 0.5px; color: rgba(255, 255, 255, 0.95);
}
.user-identity-container { display: flex; align-items: center; gap: 12px; }
.user-role-badge {
    display: inline-block; padding: 2px 6px; border-radius: 4px;
    font-size: 0.7rem; font-weight: 600; margin-left: 6px; vertical-align: middle;
}
.user-role-badge.admin { background-color: #ffd700; color: #333; box-shadow: 0 1px 3px rgba(0,0,0,0.2); }
.user-role-badge.teacher { background-color: rgba(255, 255, 255, 0.25); color: white; border: 1px solid rgba(255, 255, 255, 0.4); }

/* Navigation Icons */
.nav-icons { display: flex; gap: 0.35rem; }
.nav-icon {
    display: flex; flex-direction: column; align-items: center; justify-content: center;
    cursor: pointer; color: white; transition: all 0.2s ease-in-out;
    border: none; background: none; padding: 0.2rem; border-radius: 6px; width: 65px;
}
.nav-icon:hover { background-color: rgba(255,255,255,0.15); transform: translateY(-2px); }
.nav-icon i { font-size: 1.35rem; opacity: 0.9; color: white; }
.nav-icon span { font-size: 0.7rem; margin-top: 0.2rem; opacity: 0.9; }
#datetime-display { font-size: 1.25rem; font-weight: 600; color: white; letter-spacing: 0.5px; opacity: 0.9; }

/* Main Containers */
.page-container { padding: 0 1.5rem 1.5rem 1.5rem; display: flex; flex-grow: 1; min-height: 0; }
.main-container { display: flex; flex-grow: 1; gap: 1.5rem; min-height: 0; }

/* Content Panels */
.content-panel {
    background-color: var(--panel-bg-color); border-radius: 8px; border: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm); padding: 1.5rem; display: flex; flex-direction: column;
    overflow: hidden; transition: box-shadow 0.3s ease, transform 0.3s ease;
}
.content-panel:focus-within, .content-panel:hover { box-shadow: var(--shadow-lg); transform: translateY(-4px); }

.content-panel-left { width: calc(33.333% - 0.75rem); }
.content-panel-right { width: calc(66.667% - 0.75rem); }

/* Panel Headers */
.content-panel-left .panel-header,
.right-panel-header {
    margin: -1.5rem -1.5rem 1.5rem -1.5rem; padding: 0.75rem 1.5rem;
    border-bottom: 1px solid var(--border-color);
    background-color: var(--title-highlight-bg);
    border-top-left-radius: 8px; border-top-right-radius: 8px;
}
.content-panel-left .panel-header { font-size: 1.25rem; font-weight: 600; color: var(--primary-color); padding-top: 1rem; }
.right-panel-header h2 { font-size: 1.25rem; font-weight: 600; color: var(--primary-color); margin: 0; }
.panel-body { flex-grow: 1; overflow-y: auto; padding-right: 10px; }

/* Registration Panel Specifics */
#homeworkRegistrationPanel { display: flex; flex-direction: column; height: 100%; overflow: hidden; gap: 0.5rem; }
#registrationScrollContainer { flex: 1 1 auto; min-height: 0; overflow-y: auto; padding-right: 10px; display: flex; flex-direction: column; gap: 0.75rem; }
#registrationScrollContainer #registerHomeworkBtn { margin-top: auto; }
#homeworkRegistrationPanel .form-label { margin-bottom: 0.35rem; }

/* Student Panel Specifics */
.student-panel { height: 100%; overflow: hidden; }
.student-filter-bar { padding: 1rem 1.25rem 0 1.25rem; background-color: var(--card-header-bg); border-bottom: 1px solid var(--border-color); flex-shrink: 0; z-index: 2; }
.student-table-wrapper { flex-grow: 1; overflow-y: auto; padding: 0 1.25rem 1.25rem 1.25rem; }
.student-table-wrapper table { width: 100%; border-collapse: separate; border-spacing: 0; }
.student-table-wrapper thead.sticky-top { position: sticky; top: 0; z-index: 1; background-color: var(--panel-bg-color); }

/* ==========================================================================
   3. BASIC COMPONENTS (Buttons, Forms, Tables, Tags)
   ========================================================================== */
/* Buttons */
.btn { transition: all 0.2s ease-in-out; border-radius: 4px; font-weight: 500; }
.btn-primary { background-color: var(--primary-color); border-color: var(--primary-color); }
.btn-primary:hover {
    background-color: var(--primary-color-hover); border-color: var(--primary-color-hover);
    transform: translateY(-2px); box-shadow: 0 6px 12px rgba(0, 103, 198, 0.3);
}
.btn-danger { background-color: var(--status-red); border-color: var(--status-red); }
.btn-sm.btn-outline-success { color: var(--status-green); border-color: var(--status-green); }
.btn-sm.btn-outline-success:hover { background-color: var(--status-green); color: white; }
.btn-sm.btn-outline-danger { color: var(--status-red); border-color: var(--status-red); }
.btn-sm.btn-outline-danger:hover { background-color: var(--status-red); color: white; }
.btn-sm.btn-outline-primary { color: var(--primary-color); border-color: var(--primary-color); }
.btn-sm.btn-outline-primary:hover { background-color: var(--primary-color); color: white; }

/* Custom Datepicker/Dropdown Button Style */
.btn-datepicker-style {
    background-color: var(--panel-bg-color); color: var(--font-color);
    border: 1px solid var(--border-color); text-align: left !important;
}
.btn-datepicker-style:hover, .btn-datepicker-style:active, .btn-datepicker-style.show {
    background-color: var(--panel-bg-color); color: var(--font-color);
    border-color: var(--primary-color); box-shadow: 0 0 0 3px rgba(0, 103, 198, 0.2);
}
.btn-datepicker-style::after { color: var(--font-color); }

/* Forms */
.form-label { font-weight: 600; color: var(--font-color); }
.form-control, .form-select { border-color: var(--border-color); transition: border-color .2s ease, box-shadow .2s ease; border-radius: 4px; }
.form-control:focus, .form-select:focus {
    border-color: var(--primary-color); box-shadow: 0 0 0 3px rgba(0, 103, 198, 0.2); outline: none;
}

/* Tables */
.table thead { position: sticky; top: 0; z-index: 1; background-color: var(--panel-bg-color) !important; border-bottom: 2px solid var(--primary-color); }
.table-hover tbody tr:hover { background-color: var(--title-highlight-bg); }
.table.table-hover #contractTableBody tr:hover { background-color: #1864d657 !important; }

/* Icons & Actions */
.action-icons { display: flex; gap: 0.75rem; align-items: center; }
.action-icons i { cursor: pointer; margin: 0; font-size: 1.1rem; color: var(--secondary-color); transition: transform 0.2s, color 0.2s; }
.action-icons i:hover { transform: scale(1.25); text-shadow: 0 0 8px rgba(0,0,0,0.2); }
.action-icons .fa-edit:hover { color: var(--status-yellow); }
.action-icons .fa-trash-alt:hover { color: var(--status-red); }
.action-icons .fa-print:hover { color: var(--primary-color); }
.action-icons .fa-copy:hover { color: var(--status-green); }

/* Tags (Grade, Classmate, Checkbox) */
.grade-tags, .checkbox-tags, .classmate-tags { display: flex; flex-wrap: wrap; gap: 0.5rem; }
.checkbox-tag input { display: none; }
.checkbox-tag label {
    display: block; padding: 0.3rem 0.8rem; border: 1px solid var(--border-color);
    border-radius: 15px; cursor: pointer; transition: all 0.2s;
}
.checkbox-tag input:checked + label { background-color: var(--primary-color); color: white; border-color: var(--primary-color); }

.grade-tag, .classmate-tag {
    padding: 0.35rem 0.9rem; border: 1px solid var(--border-color); border-radius: 15px;
    cursor: pointer; transition: all 0.2s ease; font-size: 0.9rem; background-color: var(--bg-color);
}
.grade-tag:hover { border-color: var(--primary-color-hover); color: var(--primary-color-hover); }
.grade-tag.selected, .classmate-tag.selected {
    background-color: var(--primary-color); color: white; border-color: var(--primary-color); font-weight: 500;
}
.classmate-tags-container {
    display: flex; flex-direction: column; gap: 0.75rem; margin-top: 1rem;
    padding: 0.75rem; border: 1px dashed var(--border-color); border-radius: 6px;
}
#progressGradeFilter .checkbox-tag label { padding: 0.15rem 0.4rem; font-size: 0.8rem; border-radius: 10px; }

/* Subject Icons */
.subject-icon {
    display: inline-flex; flex-direction: column; align-items: center; padding: 0.75rem;
    border: 1px solid var(--border-color); border-radius: 8px; cursor: pointer; min-width: 80px; transition: all .2s ease;
}
.subject-icon i { font-size: 1.75rem; margin-bottom: 0.5rem; color: var(--secondary-color); transition: all .2s ease; }
.subject-icon span { font-size: 0.8rem; }
.subject-icon.selected, .subject-icon:hover {
    border-color: var(--primary-color); background-color: var(--title-highlight-bg);
    transform: translateY(-2px); box-shadow: var(--shadow-md);
}
.subject-icon.selected i, .subject-icon:hover i { color: var(--primary-color); }

/* Service Type Icons */
.service-type-icon {
    display: inline-flex; flex-direction: column; align-items: center; padding: 0.6rem;
    border: 1px solid var(--border-color); border-radius: 8px; cursor: pointer; min-width: 86px;
    transition: all .2s ease; background: #fff;
}
.service-type-icon i { font-size: 1.35rem; margin-bottom: 0.35rem; color: var(--secondary-color); transition: all .2s ease; }
.service-type-icon span { font-size: 0.85rem; }
.service-type-icon.selected, .service-type-icon:hover {
    border-color: var(--primary-color); background-color: var(--title-highlight-bg);
    transform: translateY(-2px); box-shadow: var(--shadow-sm);
}
.service-type-icon.selected i, .service-type-icon:hover i { color: var(--primary-color); }

/* Table Toggle Switches */
.table .form-switch {
    min-height: auto; 
    margin-bottom: 0; 
    padding-left: 0; /* 清除默认内边距以配合 flex 居中 */
    display: flex;
    justify-content: center;
    align-items: center;
}

.table .form-check-input {
    width: 2.5em;       /* 开关宽度 */
    height: 1.3em;      /* 开关高度 */
    cursor: pointer;
    margin-top: 0;      /* 修正垂直对齐 */
    float: none;        /* 防止 Bootstrap 默认浮动影响居中 */
}

/* 选中状态变成主色调 */
.table .form-check-input:checked {
    background-color: var(--primary-color); 
    border-color: var(--primary-color);
}

/* 鼠标悬停时的微交互 */
.table .form-check-input:hover {
    filter: brightness(0.95);
}

/* ==========================================================================
   4. CARDS & HOMEWORK DISPLAY
   ========================================================================== */
/* Generic Card Micro-interaction */
.student-homework-card, .dash-card, .subject-task-group {
    transition: transform 0.3s cubic-bezier(0.25, 0.8, 0.25, 1), box-shadow 0.3s ease;
}
.student-homework-card:hover, .dash-card:hover, .subject-task-group:hover {
    transform: translateY(-4px); box-shadow: 0 12px 24px rgba(0, 103, 198, 0.15);
}

/* Student Homework Card */
.student-homework-card {
    border: 1px solid var(--border-color); border-radius: 8px; margin-bottom: 1rem;
    background-color: var(--panel-bg-color); box-shadow: var(--shadow-sm);
}
.student-homework-card:hover { border-color: var(--primary-color); }
.student-homework-card-header {
    background-color: var(--primary-color); color: white; padding: 0.75rem 1.25rem;
    font-weight: 600; display: flex; justify-content: space-between; align-items: center;
    border-bottom: 1px solid var(--border-color); border-top-left-radius: 8px; border-top-right-radius: 8px;
}
.student-homework-card-header .action-icons i { color: white; opacity: 0.9; }
.student-homework-card-header .action-icons i:hover { color: #ffffff; text-shadow: 0 0 6px rgba(255,255,255,0.3); transform: scale(1.2); }
.student-homework-card-body { padding: 1.25rem; transition: background-color 0.3s ease; }

/* Homework Items */
.homework-subject-group { margin-bottom: 1rem; }
.homework-subject-title {
    font-weight: bold; color: var(--primary-color); margin-bottom: 0.75rem;
    padding-bottom: 0.5rem; border-bottom: 1px solid var(--border-color);
    display: flex; justify-content: space-between; align-items: center;
}
.homework-item {
    display: flex; align-items: center; padding: 0.5rem 0.75rem; border-bottom: 1px solid #f0f0f0;
    background: none !important; border-radius: 0;
}
.homework-item:last-child { border-bottom: none; }
.homework-text { flex-grow: 1; padding-right: 1rem; }
.homework-actions-wrapper { display: flex; align-items: center; flex-shrink: 0; gap: 0.75rem; }
.homework-status-select { width: 105px; }
.homework-date-group {
    margin-bottom: 0.75rem; padding: 0.5rem 0.75rem; border-left: 3px solid var(--primary-color);
    background-color: rgba(0,103,198,0.04); border-radius: 4px;
}
.homework-date-group .text-muted { font-weight: 600; color: var(--primary-color) !important; }

/* Subject Task Group (Input) */
.subject-task-group {
    background-color: var(--panel-bg-color); border: 1px solid var(--border-color);
    border-radius: 8px; box-shadow: var(--shadow-sm); padding: 1rem; margin-bottom: 1rem;
    overflow: hidden;
}
.subject-task-group:hover { border-color: var(--primary-color); }
.subject-task-group > label.form-label {
    display: block; margin: -1rem -1rem 1rem -1rem; background-color: var(--card-header-bg);
    color: var(--font-color); font-weight: 600; padding: 0.75rem 1.25rem;
    border-bottom: 1px solid var(--border-color); width: auto; box-sizing: border-box;
}
.subject-task-group > textarea.form-control {
    border: none; resize: vertical; padding: 0; margin-bottom: 1rem; border-radius: 0;
    background-color: var(--panel-bg-color);
}
.subject-task-group > textarea.form-control:last-child { margin-bottom: 0; }

/* Dashboard Cards */
.dash-card { background-color: var(--panel-bg-color); border: 1px solid var(--border-color); border-radius: 8px; box-shadow: var(--shadow-sm); }
.dash-card-header {
    display: flex; align-items: center; gap: .5rem; padding: .5rem .75rem; font-weight: 600;
    border-bottom: 1px solid var(--border-color); background-color: var(--card-header-bg);
}
.dash-card-header.danger { color: #c62828; }
.dash-card-header.warning { color: #f57f17; }
.dash-card-header i { font-size: 1rem; color: inherit; }
.dash-card-body { padding: .75rem .9rem; }
.dash-kpi { font-size: 2rem; font-weight: 700; color: var(--primary-color); line-height: 1.2; }
.dash-sub { font-size: .85rem; color: var(--secondary-color); }
.dash-list .dash-item { display: flex; justify-content: space-between; align-items: center; padding: .25rem 0; border-bottom: 1px dashed var(--border-color); }
.dash-list .dash-item:last-child { border-bottom: none; }
.dash-table-wrapper { max-height: 40vh; overflow-y: auto; border: 1px solid var(--border-color); border-radius: 6px; }
.dash-expired-thead { background-color: var(--status-red-bg); position: sticky; top: 0; z-index: 2; }
.dash-expiring-thead { background-color: var(--status-yellow-bg); position: sticky; top: 0; z-index: 2; }
.dash-expired-thead th, .dash-expiring-thead th { color: #000000; font-weight: 700; }

/* ==========================================================================
   5. MODALS & OVERLAYS
   ========================================================================== */
/* Generic Modal Styles */
.modal.fade .modal-dialog { transition: transform .3s ease-out, opacity .3s ease-out; transform: translateY(-20px); opacity: 0; }
.modal.show .modal-dialog {
    transform: translateY(0); opacity: 1;
    display: flex; align-items: center; justify-content: center;
    margin: 0 auto; min-height: 100vh;
}
.main-modal .modal-dialog { width: calc(100vw - 40px); max-width: calc(100vw - 40px); height: calc(100vh - 40px); max-height: calc(100vh - 40px); }
.main-modal .modal-content { height: 100%; display: flex; flex-direction: column; border-radius: 8px; border: none; box-shadow: var(--shadow-lg); }
.main-modal .modal-body { overflow-y: auto; flex-grow: 1; }
.sub-modal .modal-dialog { width: 90vw; max-width: 1200px; }
.modal-header {
    background-color: var(--primary-color); color: white; padding: 1rem 1.5rem;
    border-top-left-radius: 7px; border-top-right-radius: 7px; flex-shrink: 0;
}
.modal-header .btn-close { filter: invert(1) grayscale(100%) brightness(200%); }
.modal-footer { flex-shrink: 0; }

/* Large Screen / Full Screen Modal */
.large-screen-container { display: flex; height: 100%; gap: 1rem; }
.grade-region {
    flex: 1; border: 1px solid var(--border-color); border-radius: 8px;
    display: flex; flex-direction: column; overflow: hidden; background-color: var(--bg-color);
    position: relative;
}
.grade-region-header {
    padding: 0.75rem; font-size: 1.25rem; font-weight: 600; text-align: center;
    border-bottom: 1px solid var(--border-color); flex-shrink: 0;
    background-color: var(--primary-color); color: white;
}
.grade-region-body { padding: 1rem; overflow-y: auto; }

/* Fix 2: 仅在全屏模式下隐藏列的滚动条 */
:fullscreen .grade-region-body::-webkit-scrollbar { display: none; }
:fullscreen .grade-region-body { -ms-overflow-style: none; scrollbar-width: none; }

.large-screen-card {
    background-color: var(--panel-bg-color); border: 1px solid var(--border-color); border-radius: 8px;
    margin-bottom: 1rem; box-shadow: var(--shadow-sm); overflow: hidden; transition: all 0.3s ease;
}

/* Fix: 防止悬停时出现黑框 (原inherit导致继承文字黑颜色)，并禁用浮动 */
.large-screen-card:hover { 
    background-color: var(--panel-bg-color) ;
    border-color: var(--border-color) !important; 
    box-shadow: var(--shadow-sm) !important; 
    transform: none !important; 
}

.large-screen-card-header {
    padding: 0.5rem 1rem; font-weight: 600; display: flex; justify-content: space-between; align-items: center;
    border-bottom: 1px solid var(--border-color); background-color: #cce4f9; color: var(--font-color);
}

.large-screen-subject-group { margin-bottom: 0.5rem; }
.large-screen-subject-title {
    font-weight: bold; color: var(--primary-color); padding: 0.5rem 0.25rem;
    border-bottom: 1px solid rgba(0, 103, 198, 0.15); margin-bottom: 0.5rem; font-size: 1.05rem;
}

.large-screen-homework-item { display: flex; align-items: center; padding: 0.3rem 0.75rem; background: none !important; border-radius: 0; }
.large-screen-homework-text { word-break: break-word; white-space: pre-wrap; line-height: 1.5; }

/* Fix 3: 圆形状态图标 */
.large-screen-status-label {
    display: inline-block; flex-shrink: 0; 
    width: 22px; height: 22px; border-radius: 50%; /* 圆形 */
    margin-right: 0.75rem; 
    text-align: center; line-height: 22px;
    font-size: 0; /* 隐藏原有文字 */
    position: relative;
    box-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

/* 使用 FontAwesome 图标填充 */
.large-screen-status-label::before {
    font-family: "Font Awesome 5 Free"; font-weight: 900; font-size: 12px;
    position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%);
    color: white;
}

/* 红色 - 未完成 (叉号) */
.large-screen-status-label.status-red-bg::before { content: "\f00d"; }
/* 黄色 - 部分完成 (感叹号) - 修正文字颜色 */
.large-screen-status-label.status-yellow-bg { color: #fff !important; }
.large-screen-status-label.status-yellow-bg::before { content: "\f12a"; }
/* 绿色 - 已完成 (对钩) */
.large-screen-status-label.status-green-bg::before { content: "\f00c"; }

/* 保持原有背景色定义 */
.large-screen-container .status-red-bg { background-color: #d83b01 !important; }
.large-screen-container .status-green-bg { background-color: #107c10 !important; }
.large-screen-container .status-yellow-bg { background-color: #ffb900 !important; }

/* Fix 1: 收缩任务显示区域 (增加边距) */
.large-screen-date-group {
    margin: 0.5rem 1rem 0.75rem 1rem; /* 左右增加间距 */
    padding: 0.75rem; border-left: 3px solid var(--primary-color);
    background-color: rgba(0,103,198,0.04); border-radius: 4px;
}
.large-screen-date-group .text-muted { font-weight: 600; color: var(--primary-color) !important; margin-bottom: 0.35rem; }
.large-screen-screenshot-icon {
    cursor: pointer; margin-left: 0.75rem; color: var(--secondary-color); transition: color 0.2s, transform 0.2s;
}
.large-screen-screenshot-icon:hover { color: var(--primary-color-hover); transform: scale(1.2); }

/* Auto Scroll */
@keyframes autoscroll { from { transform: translateY(0); } to { transform: translateY(-50%); } }
.autoscroll-enabled { padding: 0; }
.autoscroll-enabled .autoscroll-content { animation: autoscroll 60s linear infinite; }
.autoscroll-enabled:hover .autoscroll-content { animation-play-state: paused; }

/* Bulk Input & OCR Modals (Unified Layout V3) */
#bulkInputModal .modal-content, #ocrInputModal .modal-content { display: flex; flex-direction: column; max-height: 80vh; }
#bulkInputModal .bulk-scroll-body, #ocrInputModal .ocr-scroll-body { overflow-y: auto; padding: 0 1rem 1rem 1rem; }
#bulkInputModal .bulk-two-col, #ocrInputModal .ocr-two-col { display: flex; gap: 1rem; align-items: stretch; }
#bulkInputModal .bulk-pane, #ocrInputModal .ocr-pane {
    flex: 1 1 0; min-height: 40vh; max-height: 52vh; overflow-y: auto;
    background: #fafafa; border-radius: 6px; padding: 0.75rem; display: flex; flex-direction: column;
}
/* Fixed heights for Bulk */
#bulkInputModal .bulk-pane textarea#bulkInputTextarea,
#bulkInputModal .bulk-pane #bulkInputPreview {
    height: 36vh; min-height: 36vh; max-height: 36vh; overflow-y: auto; resize: none;
}
#bulkInputModal .bulk-pane #bulkInputPreview { background: #fff; flex-grow: 0; }
/* OCR Specifics */
#ocrInputModal .ocr-input-dropzone {
    position: relative; border: 2px dashed var(--border-color); border-radius: 6px; padding: 0.75rem;
    background: #fff; display: flex; align-items: center; justify-content: center; overflow: hidden;
    height: 220px; min-height: 220px; max-height: 220px; flex-grow: 0;
}
#ocrInputModal .ocr-input-dropzone.dragover { border-color: var(--primary-color); background: rgba(0, 103, 198, 0.06); }
#ocrInputModal .ocr-image-preview { max-width: 100%; max-height: 100%; object-fit: contain; border-radius: 4px; display: block; }
#ocrInputModal .ocr-textarea {
    margin-top: 0.5rem; height: 210px; min-height: 210px; max-height: 210px;
    overflow-y: auto; resize: none; flex-grow: 0;
}
#ocrInputModal .ocr-preview-box {
    height: calc(220px + 0.5rem + 210px); min-height: calc(220px + 0.5rem + 210px); max-height: calc(220px + 0.5rem + 210px);
    overflow-y: auto; background: #fff; border: 1px solid var(--border-color); border-radius: 6px; padding: 0.5rem; flex-grow: 0;
}
#ocrInputModal .ocr-progress-pill {
    display: inline-flex; align-items: center; gap: 6px; padding: 6px 10px; border-radius: 16px;
    font-weight: 600; font-size: 0.85rem; background: var(--status-yellow); color: #1e1e1e; box-shadow: var(--shadow-sm);
}
#ocrInputModal .ocr-progress-pill .spinner {
    width: 14px; height: 14px; border: 2px solid rgba(255,255,255,0.6); border-top-color: #1e1e1e;
    border-radius: 50%; animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }
#ocrInputModal .ocr-progress-pill.done { background: var(--status-green); color: #fff; }
#ocrInputModal .ocr-progress-pill.error { background: var(--status-red); color: #fff; }

/* Progress Modal */
#progressModal .table-responsive { max-height: 90vh; overflow-y: auto; }
#progressModal .table { width: 100%; border-collapse: collapse; font-size: 0.9rem; margin-bottom: 0; }
#progressModal .table th {
    background-color: #343a40; color: #ffffff; border: 1px solid #dee2e6; padding: 0.5rem 0.4rem;
    vertical-align: middle; text-align: center; font-weight: 600; position: sticky; top: 0; z-index: 10;
}
#progressModal .table td { border: 1px solid #dee2e6; padding: 0.4rem 0.4rem; vertical-align: middle; text-align: center; transition: background-color 0.15s ease-in-out; }
#progressModal .table .status-completed { background-color: #e6f7ec; color: #28a745; font-weight: 500; }
#progressModal .table .status-partial { background-color: #fff8e1; color: #ffa000; font-weight: 500; }
#progressModal .table .status-uncompleted { background-color: #fbe9e7; color: #d32f2f; font-weight: 500; }
#progressModal .table .status-none { background-color: #f5f5f5; color: #757575; }
#progressModal #progressTableBody tr:hover td { background-color: #e7f7a3; }
#progressModal #progressTableBody tr:hover .status-completed { background-color: #d4f0df; }
#progressModal #progressTableBody tr:hover .status-partial { background-color: #fbecd4; }
#progressModal #progressTableBody tr:hover .status-uncompleted { background-color: #f8e1de; }
#progressModal #progressTableBody tr:hover .status-none { background-color: #ebebeb; }
#progressTableBody span { padding: 0.2em 0.6em; border-radius: 4px; font-weight: 500; font-size: 0.8rem; }
.status-uncompleted-text { color: #c62828; background-color: var(--status-red-bg); }
.status-partial-text { color: #f57f17; background-color: var(--status-yellow-bg); }
.status-completed-text { color: #2e7d32; background-color: var(--status-green-bg); }
.status-none-text { color: #4a5568; background-color: var(--status-gray-bg); }

/* Progress Detail Popover */
.progress-detail-overlay {
    position: fixed; top: 0; left: 0; width: 100vw; height: 100vh;
    background-color: rgba(0, 0, 0, 0.5); z-index: 2050;
    display: flex; align-items: center; justify-content: center;
    backdrop-filter: blur(2px); opacity: 0; transition: opacity 0.2s ease;
}
.progress-detail-overlay.show { opacity: 1; }
.progress-detail-card {
    background-color: var(--panel-bg-color); width: 90%; max-width: 600px; max-height: 80vh;
    border-radius: 8px; box-shadow: var(--shadow-lg); display: flex; flex-direction: column; overflow: hidden;
    transform: scale(0.95); transition: transform 0.2s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}
.progress-detail-overlay.show .progress-detail-card { transform: scale(1); }
.progress-detail-header {
    background-color: var(--primary-color); color: white; padding: 0.75rem 1.25rem;
    display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; flex-shrink: 0;
}
.progress-detail-header h5 {
    margin: 0; font-size: 1.1rem; font-weight: 600; justify-self: start;
    white-space: nowrap; overflow: hidden; text-overflow: ellipsis; max-width: 100%;
}
.progress-screenshot-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    font-size: 1.1rem;
    color: rgba(255, 255, 255, 0.85);
    justify-self: center;
    cursor: pointer;
    transition: all 0.2s cubic-bezier(0.25, 0.8, 0.25, 1);
    padding: 0;
}

.progress-screenshot-btn:hover {
    color: #ffffff;
    background-color: rgba(255, 255, 255, 0.25); 
    transform: scale(1.15); 
    box-shadow: 0 0 12px rgba(255, 255, 255, 0.3);
}

.progress-screenshot-btn i,
.progress-screenshot-btn::before {
    display: inline-block;
    vertical-align: middle;
    line-height: 1;
    margin: 0;
    padding: 0;
}
.progress-detail-header .btn-close { justify-self: end; margin: 0; }
.progress-detail-body { padding: 1rem; overflow-y: auto; }
.detail-group-title {
    font-weight: bold; color: var(--primary-color); margin-top: 0.75rem; margin-bottom: 0.5rem;
    border-bottom: 1px solid var(--border-color); padding-bottom: 0.25rem; font-size: 0.95rem;
}
.detail-date-label {
    font-size: 0.85rem; font-weight: 600; color: var(--secondary-color);
    margin: 0.5rem 0 0.25rem 0; padding-left: 0.5rem; border-left: 3px solid var(--border-color);
}
.detail-task-row { display: flex; align-items: center; padding: 0.5rem 0; border-bottom: 1px dashed #eee; gap: 0.75rem; }
.detail-task-row:last-child { border-bottom: none; }
.detail-status-pill {
    flex-shrink: 0; font-size: 0.75rem; padding: 2px 8px; border-radius: 4px; font-weight: 600; width: 70px; text-align: center;
}
.detail-status-pill.completed { background-color: var(--status-green-bg); color: #2e7d32; }
.detail-status-pill.partial { background-color: var(--status-yellow-bg); color: #f57f17; }
.detail-status-pill.uncompleted { background-color: var(--status-red-bg); color: #c62828; }
.detail-task-text { flex-grow: 1; font-size: 0.9rem; font-weight: 500; color: var(--font-color); line-height: 1.5; word-break: break-word; }
.detail-status-select {
    width: auto; min-width: 90px; padding: 2px 24px 2px 8px; font-size: 0.8rem; font-weight: 600;
    border-radius: 12px; border: 1px solid var(--border-color); background-position: right 4px center; cursor: pointer;
}
.detail-status-select.uncompleted { background-color: var(--status-red-bg); color: #c62828; border-color: #f5c6cb; }
.detail-status-select.partial { background-color: var(--status-yellow-bg); color: #f57f17; border-color: #ffeeba; }
.detail-status-select.completed { background-color: var(--status-green-bg); color: #2e7d32; border-color: #c3e6cb; }
.capturing-mode { background-color: #fff !important; border-radius: 0 !important; box-shadow: none !important; }

/* ==========================================================================
   6. FLOATING ELEMENTS & PLUGINS
   ========================================================================== */
/* Toast */
.toast-container { position: fixed; top: 20px; right: 20px; z-index: 1080; }
.custom-toast {
    display: flex; align-items: center; padding: 1rem 1.5rem; color: white; border-radius: 8px;
    box-shadow: var(--shadow-lg); opacity: 0; transition: opacity 0.3s, transform 0.3s; transform: translateX(100%);
}
.custom-toast.show { opacity: 1; transform: translateX(0); }
.custom-toast.success { background-color: var(--status-green); }
.custom-toast.error { background-color: var(--status-red); }
.custom-toast.info { background-color: var(--primary-color); }

/* Login Overlay (Education Style) */
#loginOverlay {
    background-color: transparent !important;
    background-image:
        radial-gradient(1200px 600px at 8% 18%, rgba(0,103,198,0.10), transparent 16%),
        radial-gradient(900px 500px at 92% 82%, rgba(0,150,200,0.06), transparent 20%),
        linear-gradient(180deg, #f8fbff 0%, var(--bg-color) 100%);
    background-repeat: no-repeat; position: fixed; inset: 0;
    display: flex; align-items: center; justify-content: center; z-index: 2000; overflow: hidden;
    transition: opacity .45s ease, visibility .45s ease;
}
#loginOverlay::before, #loginOverlay::after {
    content: ""; position: absolute; pointer-events: none; filter: blur(28px); opacity: 0.34;
}
#loginOverlay::before {
    left: -12%; top: -8%; width: 62%; height: 62%;
    background: radial-gradient(circle at 30% 30%, rgba(255,255,255,0.85), rgba(255,255,255,0.02) 40%); transform: rotate(-12deg);
}
#loginOverlay::after {
    right: -12%; bottom: -6%; width: 62%; height: 62%;
    background: radial-gradient(circle at 70% 70%, rgba(0,103,198,0.12), rgba(0,103,198,0) 40%); transform: rotate(8deg);
}
#loginOverlay .login-grid {
    position: absolute; inset: 0; pointer-events: none; z-index: 2;
    background-image: linear-gradient(rgba(255,255,255,0.03) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,0.03) 1px, transparent 1px);
    background-size: 30px 30px; mix-blend-mode: overlay; opacity: 0.20;
}
#loginOverlay .login-decor { position: absolute; inset:0; pointer-events: none; z-index: 3; }
#loginOverlay .login-decor .decor-icon {
    position: absolute; font-size: 68px; opacity: 0.08; color: var(--primary-color);
    transform-origin: center; filter: drop-shadow(0 6px 16px rgba(0,0,0,0.06));
}
#loginOverlay .login-decor .book  { left: 6%;  top: 18%; transform: rotate(-12deg); }
#loginOverlay .login-decor .pencil { right: 8%; bottom: 20%; transform: rotate(18deg); }
#loginOverlay .login-decor .cap    { left: 50%; top: 6%; transform: translateX(-50%) rotate(6deg); }

#loginBox {
    position: relative; z-index: 10; width: min(420px, 92%); padding: 2.25rem;
    border-radius: 14px; background: linear-gradient(180deg, rgba(255,255,255,0.96), rgba(255,255,255,0.84));
    box-shadow: 0 20px 60px rgba(3,46,86,0.18), 0 6px 20px rgba(3,46,86,0.08);
    border: 1px solid rgba(0,0,0,0.04); backdrop-filter: blur(8px) saturate(120%);
    -webkit-backdrop-filter: blur(8px) saturate(120%);
    transition: transform .35s ease, box-shadow .35s ease; animation: floatCard 6s ease-in-out infinite;
}
#loginBox::before {
    content: ""; position: absolute; left: 50%; transform: translateX(-50%); top: -12px;
    width: 88px; height: 8px; border-radius: 12px;
    background: linear-gradient(90deg, var(--primary-color), var(--primary-color-hover));
    box-shadow: 0 8px 20px rgba(0,103,198,0.18);
}
@keyframes floatCard { 0% { transform: translateY(0); } 50% { transform: translateY(-8px); } 100% { transform: translateY(0); } }
#loginBox .fas.fa-user-graduate { font-size: 3rem; color: var(--primary-color); margin-bottom: 1rem; text-shadow: 0 4px 18px rgba(0,103,198,0.08); }
#loginBox h3 { margin-bottom: 1.2rem; color: var(--font-color); font-weight:600; }
#loginBox .form-control { border-radius: 8px; padding: .62rem .75rem; border: 1px solid var(--border-color); box-shadow: none; }
#loginBox .btn-primary { border-radius: 8px; padding: .58rem 1rem; font-weight: 600; box-shadow: 0 10px 30px rgba(0,103,198,0.16); }
@media (max-width: 420px) {
  #loginOverlay .login-decor .decor-icon { font-size:46px; }
  #loginBox { padding: 1.2rem; border-radius: 12px; }
}

/* Floating Name Card */
.floating-name-card {
    position: absolute; bottom: 1rem; right: 1rem; max-height: 25vh; overflow-y: auto;
    background: rgba(255, 255, 255, 0.015); border: 1px solid var(--border-color); border-radius: 10px;
    box-shadow: 0 8px 20px rgba(0, 103, 198, 0.25); padding: 0.5rem 0.75rem;
    backdrop-filter: blur(6px); -webkit-backdrop-filter: blur(6px); font-size: 0.85rem; z-index: 2000;
}
.floating-name-card::-webkit-scrollbar { width: 0px; }
.floating-name-card ul { list-style: none; margin: 0; padding: 0; }
.floating-name-card ul li {
    padding: 0.25rem 0; border-bottom: 1px dashed var(--border-color); color: var(--font-color);
    font-weight: 600; font-size: 0.8rem; display: flex; align-items: center; gap: 6px;
}
.floating-name-card ul li:last-child { border-bottom: none; }
.floating-name-card .indicator {
    display: inline-block; flex-shrink: 0; width: 10px; height: 10px; border-radius: 50%;
    background-color: #6c757d; opacity: 0.4; transition: background-color 0.3s ease, opacity 0.3s ease, box-shadow 0.3s ease;
}
.floating-name-card .indicator.is-visible {
    background-color: #107c10; opacity: 1; box-shadow: 0 0 5px #107c10; animation: blink 1.2s infinite ease-in-out;
}
@keyframes blink { 0%, 100% { transform: scale(1); opacity: 1; } 50% { transform: scale(0.7); opacity: 0.6; } }

/* Contract/Status Helpers */
#contractTableBody .status-cell span { padding: 0.2em 0.6em; border-radius: 4px; font-weight: 500; font-size: 0.8rem; }
#contractTableBody .status-valid { color: #2e7d32; background-color: var(--status-green-bg); }
#contractTableBody .status-warning { color: #f57f17; background-color: var(--status-yellow-bg); }
#contractTableBody .status-expired { color: #c62828; background-color: var(--status-red-bg); }
#contractTableBody .status-archived { color: #4a5568; background-color: var(--status-gray-bg); }
#contractTableBody .status-renewed { color: #1565c0; background-color: var(--status-blue-bg); }
#contractTableBody .status-terminated { color: #b71c1c; background-color: var(--status-light-red-bg); }

.overlap-group-card { border: 1px solid #f5c6cb; background-color: #fff; border-radius: 6px; margin-bottom: 1rem; overflow: hidden; }
.overlap-group-header { background-color: #fde8e8; padding: 0.5rem 1rem; font-weight: 600; color: #333333; border-bottom: 1px solid #f5c6cb; }
.overlap-group-body { padding: 0.75rem 1rem; }
.overlap-item { padding: 0.5rem 0; border-bottom: 1px dashed #eee; font-size: 0.9rem; display: flex; justify-content: space-between; align-items: center; }
.overlap-item:last-child { border-bottom: none; }
.date-highlight-conflict { color: #d83b01; font-weight: 700; background-color: #ffebee; padding: 2px 6px; border-radius: 4px; border: 1px solid #ffcdd2; }

/* Filter Dropdown UI */
.dropdown-menu[aria-labelledby="filterStudentNameBtn"],
.dropdown-menu[aria-labelledby="filterCompletionStatusBtn"] {
    padding: 0; border: 1px solid var(--border-color); border-radius: 3px;
    box-shadow: var(--shadow-md); max-height: 60vh; overflow-y: auto;
}
.dropdown-menu .dropdown-menu-header {
    position: sticky; top: 0; z-index: 10; background-color: var(--card-header-bg); color: var(--primary-color);
    padding: 0.75rem 1rem; display: flex; justify-content: space-between; align-items: center;
    border-bottom: 1px solid var(--border-color); font-size: 0.9rem; font-weight: 600;
}
#clearStudentFilterIcon { cursor: pointer; color: var(--secondary-color); font-size: 1rem; }
#clearStudentFilterIcon:hover { color: var(--status-red); transform: scale(1.1); }
.dropdown-menu .dropdown-menu-list { max-height: 250px; overflow-y: auto; padding: 0.25rem 0; }
.dropdown-menu .form-check { padding: 0.25rem 1rem; transition: background-color 0.2s ease; cursor: pointer; }
.dropdown-menu .form-check:hover { background-color: var(--title-highlight-bg); }
.dropdown-menu .form-check-label { font-size: 0.8rem; font-weight: 500; white-space: nowrap; cursor: pointer; }
.dropdown-menu .dropdown-menu-list::-webkit-scrollbar, #filterStudentNameContainer::-webkit-scrollbar { width: 4px; }
.dropdown-menu .dropdown-menu-list::-webkit-scrollbar-track, #filterStudentNameContainer::-webkit-scrollbar-track { background: var(--panel-bg-color); }
.dropdown-menu .dropdown-menu-list::-webkit-scrollbar-thumb, #filterStudentNameContainer::-webkit-scrollbar-thumb { background: var(--primary-color); border-radius: 3px; }
.dropdown-menu .dropdown-menu-list::-webkit-scrollbar-thumb:hover, #filterStudentNameContainer::-webkit-scrollbar-thumb:hover { background: #ffb900; }
.dropdown-menu .dropdown-item-text { display: flex; align-items: flex-start; padding: 0.35rem 1rem; }
.dropdown-menu .dropdown-item-text .form-check-input { flex-shrink: 0; margin-top: 0.2em; }

/* Network Status */
.network-status {
    position: fixed; bottom: 1px; left: 1px; transform: translateY(-50%);
    padding: 8px 12px; border-radius: 20px; font-size: 0.8rem; font-weight: 500;
    z-index: 9999; opacity: 0.8; transition: all 0.3s ease; backdrop-filter: blur(10px); box-shadow: var(--shadow-md);
}
.network-status.online { background-color: var(--status-green); color: white; }
.network-status.offline { background-color: var(--status-red); color: white; }
.network-status.syncing { background-color: var(--status-yellow); color: var(--font-color); }
.network-status.error { background-color: var(--status-red); color: white; }

/* Screen Lock */
.screen-lock-overlay {
    position: fixed; top: 0; left: 0; width: 100vw; height: 100vh; z-index: 9999;
    background-color: rgba(0, 0, 0, 0.6); backdrop-filter: blur(5px); -webkit-backdrop-filter: blur(5px);
    display: flex; justify-content: center; align-items: center; transition: opacity 0.3s ease;
}
body.screen-locked { overflow: hidden !important; }

/* ==========================================================================
   7. DARK MODE STYLES
   ========================================================================== */
#largeScreenModalBody.dark-mode { background-color: #121212 !important; }
#largeScreenModalBody.dark-mode .grade-region { background-color: #00000000; border-color: #00000000; }
#largeScreenModalBody.dark-mode .grade-region-header { background-color: #00000000; color: #f1f1f1; border-bottom-color: #00000000; }

#largeScreenModalBody.dark-mode .large-screen-card,
#largeScreenModalBody.dark-mode .student-homework-card,
#largeScreenModalBody.dark-mode .dash-card,
#largeScreenModalBody.dark-mode .subject-task-group {
    background-color: #2b2b2b; border: 1px solid #444; box-shadow: 0 4px 12px rgba(0,0,0,0.3);
}

#largeScreenModalBody.dark-mode .large-screen-card-header,
#largeScreenModalBody.dark-mode .student-homework-card-header,
#largeScreenModalBody.dark-mode .dash-card-header,
#largeScreenModalBody.dark-mode .subject-task-group > label.form-label {
    background-color: #0078d4; color: #ffffff; border-bottom-color: #555;
}

#largeScreenModalBody.dark-mode .large-screen-subject-title { color: #e0e0e0; border-bottom-color: rgba(255, 255, 255, 0.1); }
#largeScreenModalBody.dark-mode .large-screen-homework-text { color: #c5c5c5; }
#largeScreenModalBody.dark-mode .text-muted { color: #6c757d !important; }

#largeScreenModalBody.dark-mode .large-screen-status-label { color: #ffffff; font-weight: bold; }
#largeScreenModalBody.dark-mode .status-red-bg { background-color: #d83b01; }
#largeScreenModalBody.dark-mode .status-green-bg { background-color: #107c10; }
#largeScreenModalBody.dark-mode .status-yellow-bg { background-color: #ffb900; color: #1e1e1e; }

#largeScreenModalBody.dark-mode .student-homework-card-body { background-color: #2b2b2b; color: #e0e0e0; }

#largeScreenModalBody.dark-mode .large-screen-card:hover,
#largeScreenModalBody.dark-mode .student-homework-card:hover,
#largeScreenModalBody.dark-mode .subject-task-group:hover {
    border-color: #0078d4 !important; 
    box-shadow: 0 10px 24px rgba(0,103,198,0.3) !important; 
    background-color: #333333 !important;
}

#largeScreenModalBody.dark-mode .action-icons i:hover { text-shadow: 0 0 6px rgba(255,255,255,0.2); }
#largeScreenModalBody.dark-mode .large-screen-date-group .text-muted { color: #ffffff !important; font-weight: 600; }
#largeScreenModalBody.dark-mode .large-screen-homework-text { color: #ffffff; font-weight: 500; }

#largeScreenModalBody.dark-mode .large-screen-screenshot-icon,
#largeScreenModalBody.dark-mode .large-screen-screenshot-icon:hover { color: #ffffff; opacity: 0.9; text-shadow: 0 0 6px rgba(255,255,255,0.3); }

#largeScreenModalBody.dark-mode .large-screen-homework-item { background: none !important; }

#largeScreenModalBody.dark-mode .floating-name-card ul li { color: #ffffff; font-weight: 600; font-size: 0.8rem; text-shadow: 0 0 2px #000; }
#largeScreenModalBody.dark-mode .floating-name-card .indicator.is-visible { background-color: #37ed31; box-shadow: 0 0 6px #d4ed31; }

/* ==========================================================================
   8. PRINT STYLES
   ========================================================================== */
@media print {
  .student-homework-card .table td,
  .student-homework-card .table th {
    font-size: 1.1rem; line-height: 1.6;
  }
}

/* ==========================================================================
   9. DASHBOARD EXPANSION (Receivables & Accordion)
   ========================================================================== */
/* 详情模态框表格样式 */
.receivable-table {
    border-collapse: separate; 
    border-spacing: 0; 
    width: 100%;
}

/* 姓名行（一级行）样式 */
.receivable-student-row {
    cursor: pointer;
    background-color: #f8f9fa;
    transition: background-color 0.2s ease;
}
.receivable-student-row:hover {
    background-color: #e9ecef;
}
.receivable-student-row td {
    padding: 12px 15px;
    border-bottom: 1px solid var(--border-color);
    font-weight: 600;
    color: var(--font-color);
}

/* 吸顶核心代码 */
.receivable-student-row.sticky-name {
    position: sticky;
    top: 0; /* 吸顶位置 */
    z-index: 10; /* 保证在普通行之上 */
    box-shadow: 0 2px 4px rgba(0,0,0,0.05); /* 吸顶时加个阴影区分 */
}
/* 当该行处于展开状态时，颜色加深一点 */
.receivable-student-row.expanded {
    background-color: #e7f1ff; 
    color: var(--primary-color);
    border-bottom: 2px solid var(--primary-color);
}

/* 详情行（二级表格容器） */
.receivable-detail-row {
    display: none; /* 默认隐藏 */
    background-color: #fff;
}
.receivable-detail-row.show {
    display: table-row; /* 展开显示 */
    animation: fadeInRow 0.3s ease;
}
@keyframes fadeInRow { from { opacity: 0; } to { opacity: 1; } }

/* 内部嵌套表格 */
.receivable-inner-table {
    width: 96%;
    margin: 10px auto;
    border: 1px solid #eee;
    font-size: 0.9rem;
}
.receivable-inner-table thead th {
    background-color: #f1f1f1 !important;
    color: #555;
    font-weight: 600;
    padding: 8px;
    border-bottom: 1px solid #ddd;
}
.receivable-inner-table tbody td {
    padding: 8px;
    border-bottom: 1px solid #eee;
    color: #666;
    vertical-align: middle;
}

/* 金额高亮 */
.amt-highlight {
    font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    font-weight: 700;
    color: var(--status-red); 
}
.amt-total {
    font-size: 1.1rem;
    color: var(--status-red);
}

/* 箭头旋转动画 */
.fa-chevron-right {
    transition: transform 0.3s ease;
}
.receivable-student-row.expanded .fa-chevron-right {
    transform: rotate(90deg);
}