/* ==========================================================================
   تطبيق إدارة نقاط التلاميذ - أنماط CSS شاملة
   تم التطوير بواسطة: عبد الرحيم بوعلي
   ========================================================================== */

/* ==========================================================================
   المتغيرات والأساسيات
   ========================================================================== */
:root {
    /* الألوان الرئيسية */
    --primary-color: #667eea;
    --primary-dark: #5a6fd8;
    --primary-light: #a3b5ff;
    --secondary-color: #764ba2;
    --accent-color: #4facfe;
    --accent-dark: #0095ff;
    
    /* ألوان الحالة */
    --success-color: #28a745;
    --success-dark: #218838;
    --warning-color: #ffc107;
    --warning-dark: #e0a800;
    --danger-color: #dc3545;
    --danger-dark: #c82333;
    --info-color: #17a2b8;
    
    /* ألوان النص والخلفية */
    --text-color: #2c3e50;
    --text-light: #6c757d;
    --text-lighter: #adb5bd;
    --bg-color: #ffffff;
    --bg-light: #f8f9fa;
    --bg-lighter: #f1f3f4;
    --border-color: #dee2e6;
    --border-light: #e9ecef;
    
    /* الظلال */
    --shadow-sm: 0 2px 4px rgba(0,0,0,0.1);
    --shadow-md: 0 4px 6px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 15px rgba(0,0,0,0.1);
    --shadow-xl: 0 20px 25px rgba(0,0,0,0.15);
    
    /* الزوايا */
    --border-radius-sm: 8px;
    --border-radius: 12px;
    --border-radius-lg: 16px;
    --border-radius-xl: 20px;
    
    /* التحولات */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
    
    /* المسافات */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    --spacing-xxl: 48px;
}

/* إعادة الضبط والأساسيات */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Tajawal', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    min-height: 100vh;
    line-height: 1.6;
    color: var(--text-color);
    font-weight: 400;
    padding: var(--spacing-md);
}

/* ==========================================================================
   الحاوية الرئيسية والتخطيط
   ========================================================================== */
.container {
    max-width: 1400px;
    margin: 0 auto;
    background: var(--bg-color);
    border-radius: var(--border-radius-xl);
    box-shadow: var(--shadow-xl);
    overflow: hidden;
    position: relative;
    min-height: calc(100vh - var(--spacing-md) * 2);
}

/* ==========================================================================
   قسم الهيرو
   ========================================================================== */
.hero-section {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    padding: var(--spacing-xl);
    position: relative;
    overflow: hidden;
}

.hero-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1000 1000" opacity="0.1"><polygon fill="white" points="0,1000 1000,0 1000,1000"/></svg>');
    background-size: cover;
}

.hero-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    max-width: 1200px;
    margin: 0 auto;
    position: relative;
    z-index: 2;
    gap: var(--spacing-xl);
}

.hero-text {
    flex: 1;
}

.hero-title {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: var(--spacing-md);
    line-height: 1.2;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
    animation: fadeInUp 0.8s ease;
}

.hero-subtitle {
    font-size: 1.3rem;
    font-weight: 300;
    margin-bottom: var(--spacing-lg);
    opacity: 0.9;
    line-height: 1.5;
    animation: fadeInUp 0.8s ease 0.2s both;
}

.hero-features {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
    animation: fadeInUp 0.8s ease 0.4s both;
}

.feature {
    background: rgba(255,255,255,0.2);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: 20px;
    font-size: 0.9rem;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255,255,255,0.3);
    transition: var(--transition-normal);
}

.feature:hover {
    background: rgba(255,255,255,0.3);
    transform: translateY(-2px);
}

.hero-image {
    /*flex: 0 0 300px;
    text-align: center;
    position: relative;*/
    width: 400px;
    height: 250px;
    object-fit: cover;
}

.hero-image img {
    max-width: 100%;
    height: auto;
    filter: drop-shadow(0 10px 20px rgba(0,0,0,0.3));
    animation: float  3s ease-in-out infinite;
}

.image-placeholder {
    display: none;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: rgba(255,255,255,0.1);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-xl);
    backdrop-filter: blur(10px);
    border: 2px dashed rgba(255,255,255,0.3);
}

.placeholder-icon {
    font-size: 4rem;
    margin-bottom: var(--spacing-md);
    opacity: 0.8;
}

.hero-image img[style*="display: none"] + .image-placeholder {
    display: flex;
    animation: fadeIn 0.5s ease;
}

/* ==========================================================================
   المحتوى الرئيسي
   ========================================================================== */
.main-content {
    padding: 0;
}

/* ==========================================================================
   التبويبات
   ========================================================================== */
.nav-tabs {
    display: flex;
    background: var(--bg-light);
    border-bottom: 1px solid var(--border-color);
    overflow-x: auto;
    scrollbar-width: none;
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-tabs::-webkit-scrollbar {
    display: none;
}

.nav-tab {
    padding: var(--spacing-lg) var(--spacing-xl);
    background: none;
    border: none;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 500;
    transition: var(--transition-normal);
    flex: 1;
    min-width: 140px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    white-space: nowrap;
    color: var(--text-light);
    position: relative;
    overflow: hidden;
}

.nav-tab::before {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 3px;
    background: var(--primary-color);
    transition: var(--transition-normal);
    transform: translateX(-50%);
}

.nav-tab.active {
    background: var(--bg-color);
    color: var(--primary-color);
    font-weight: 700;
}

.nav-tab.active::before {
    width: 100%;
}

.nav-tab:hover {
    background: var(--bg-lighter);
    color: var(--primary-dark);
}

.tab-icon {
    font-size: 1.2em;
    transition: var(--transition-normal);
}

.nav-tab:hover .tab-icon {
    transform: scale(1.1);
}

/* ==========================================================================
   محتوى التبويبات
   ========================================================================== */
.tab-content {
    display: none;
    padding: var(--spacing-xl);
    animation: fadeIn 0.3s ease;
}

.tab-content.active {
    display: block;
}

/* ==========================================================================
   قسم الاستيراد
   ========================================================================== */
.upload-section {
    text-align: center;
    padding: var(--spacing-xxl) var(--spacing-xl);
    border: 3px dashed var(--accent-color);
    border-radius: var(--border-radius-lg);
    margin-bottom: var(--spacing-lg);
    background: var(--bg-lighter);
    transition: var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.upload-section::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: linear-gradient(45deg, transparent, rgba(79, 172, 254, 0.1), transparent);
    transition: var(--transition-normal);
    transform: rotate(45deg);
}

.upload-section:hover {
    border-color: var(--primary-color);
    background: var(--bg-light);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.upload-section:hover::before {
    transform: rotate(45deg) translate(10%, 10%);
}

.upload-icon {
    font-size: 3rem;
    margin-bottom: var(--spacing-md);
    opacity: 0.7;
}

.upload-section h3 {
    font-size: 1.5rem;
    color: var(--primary-color);
    margin-bottom: var(--spacing-sm);
    font-weight: 600;
}

.upload-section p {
    color: var(--text-light);
    margin-bottom: var(--spacing-lg);
    font-size: 1.1rem;
}

.file-requirements {
    font-size: 0.9rem;
    color: var(--text-lighter);
    margin-top: var(--spacing-md);
}

.upload-btn {
    background: linear-gradient(45deg, var(--primary-color), var(--primary-dark));
    color: white;
    border: none;
    padding: var(--spacing-md) var(--spacing-xl);
    border-radius: 25px;
    font-size: 1rem;
    cursor: pointer;
    transition: var(--transition-normal);
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
    position: relative;
    overflow: hidden;
}

.upload-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
    transition: var(--transition-normal);
}

.upload-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.6);
}

.upload-btn:hover::before {
    left: 100%;
}

.file-input {
    display: none;
}

/* ==========================================================================
   محدد الصفحات
   ========================================================================== */
.sheet-selector {
    margin: var(--spacing-lg) 0;
    text-align: center;
    display: none;
}

.sheet-selector label {
    font-weight: 600;
    color: var(--text-color);
    margin-left: var(--spacing-sm);
}

.sheet-selector select {
    padding: var(--spacing-md) var(--spacing-lg);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 1rem;
    min-width: 250px;
    font-family: 'Tajawal', sans-serif;
    transition: var(--transition-normal);
    background: var(--bg-color);
    cursor: pointer;
}

.sheet-selector select:focus {
    border-color: var(--primary-color);
    outline: none;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

/* ==========================================================================
   قسم المعاينة
   ========================================================================== */
.preview-section {
    display: none;
}

.selection-info {
    background: #e8f4fd;
    padding: var(--spacing-lg);
    border-radius: var(--border-radius-lg);
    margin-bottom: var(--spacing-lg);
    border-right: 4px solid var(--primary-color);
}

.selection-info h4 {
    color: var(--primary-dark);
    margin-bottom: var(--spacing-md);
    font-weight: 700;
}

.selection-info ul {
    color: var(--text-color);
    margin-right: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
}

.selection-info li {
    margin-bottom: var(--spacing-sm);
    line-height: 1.5;
}

.column-info {
    background: #fff3cd;
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    margin: var(--spacing-md) 0;
    border-right: 4px solid var(--warning-color);
    display: none;
}

.student-rows-info {
    background: #d4edda;
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    margin: var(--spacing-md) 0;
    border-right: 4px solid var(--success-color);
    display: none;
}

.bulk-selection {
    display: flex;
    gap: var(--spacing-sm);
    margin: var(--spacing-md) 0;
    flex-wrap: wrap;
}

.bulk-btn {
    background: #6c757d;
    color: white;
    border: none;
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--border-radius);
    cursor: pointer;
    font-size: 0.875rem;
    transition: var(--transition-normal);
    font-weight: 500;
}

.bulk-btn:hover {
    background: #5a6268;
    transform: translateY(-1px);
}

/* ==========================================================================
   قسم معالجة جميع الصفحات
   ========================================================================== */
.bulk-processing-section {
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    padding: var(--spacing-xl);
    border-radius: var(--border-radius-lg);
    margin: var(--spacing-lg) 0;
    border: 2px solid var(--primary-light);
    position: relative;
    overflow: hidden;
}

.bulk-processing-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
}

.bulk-processing-header {
    text-align: center;
    margin-bottom: var(--spacing-lg);
}

.bulk-processing-header h3 {
    color: var(--primary-color);
    margin-bottom: var(--spacing-sm);
    font-weight: 700;
}

.bulk-processing-header p {
    color: var(--text-light);
    font-size: 1rem;
}

.bulk-processing-controls {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: var(--spacing-lg);
}

.bulk-processing-results {
    background: var(--bg-color);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
    animation: fadeIn 0.5s ease;
}

.results-summary {
    margin-bottom: var(--spacing-lg);
}

.results-summary h4 {
    color: var(--primary-color);
    margin-bottom: var(--spacing-md);
    border-bottom: 2px solid var(--primary-light);
    padding-bottom: var(--spacing-sm);
}

.processing-summary {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-md);
}

.summary-item {
    background: var(--bg-light);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    text-align: center;
    border-left: 4px solid var(--primary-color);
}

.summary-number {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--primary-color);
    display: block;
}

.summary-label {
    font-size: 0.875rem;
    color: var(--text-light);
    margin-top: var(--spacing-xs);
}

.sheets-preview h4 {
    color: var(--primary-color);
    margin-bottom: var(--spacing-md);
    border-bottom: 2px solid var(--primary-light);
    padding-bottom: var(--spacing-sm);
}

.processed-sheets-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: var(--spacing-md);
}

.sheet-card {
    background: var(--bg-light);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    border: 1px solid var(--border-color);
    transition: var(--transition-normal);
    position: relative;
}

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

.sheet-card-header {
    display: flex;
    justify-content: between;
    align-items: center;
    margin-bottom: var(--spacing-sm);
}

.sheet-name {
    font-weight: 600;
    color: var(--text-color);
    font-size: 1.1rem;
}

.sheet-stats {
    display: flex;
    gap: var(--spacing-md);
    margin-top: var(--spacing-sm);
}

.sheet-stat {
    text-align: center;
    flex: 1;
}

.sheet-stat-number {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary-color);
    display: block;
}

.sheet-stat-label {
    font-size: 0.75rem;
    color: var(--text-light);
}

.sheet-actions {
    display: flex;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-md);
}

.sheet-action-btn {
    flex: 1;
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: 0.75rem;
    border: none;
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    transition: var(--transition-normal);
}

.sheet-action-preview {
    background: var(--info-color);
    color: white;
}

.sheet-action-export {
    background: var(--success-color);
    color: white;
}

.sheet-action-btn:hover {
    opacity: 0.9;
    transform: translateY(-1px);
}

/* ==========================================================================
   عناصر التحكم
   ========================================================================== */
.controls {
    display: flex;
    gap: var(--spacing-md);
    margin: var(--spacing-lg) 0;
    flex-wrap: wrap;
    align-items: center;
}

.search-container {
    position: relative;
    flex: 1;
    min-width: 250px;
}

.search-box {
    width: 100%;
    padding: var(--spacing-md) var(--spacing-lg) var(--spacing-md) 3rem;
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 1rem;
    font-family: 'Tajawal', sans-serif;
    transition: var(--transition-normal);
    background: var(--bg-color);
}

.search-box:focus {
    border-color: var(--primary-color);
    outline: none;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.search-icon {
    position: absolute;
    left: var(--spacing-md);
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-light);
    pointer-events: none;
}

.search-info {
    padding: var(--spacing-md);
    background: #e8f4fd;
    border-radius: var(--border-radius);
    margin-bottom: var(--spacing-md);
    text-align: center;
    color: var(--text-color);
    display: none;
}

/* ==========================================================================
   الأزرار
   ========================================================================== */
.btn {
    background: var(--success-color);
    color: white;
    border: none;
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--border-radius);
    cursor: pointer;
    font-size: 0.875rem;
    transition: var(--transition-normal);
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    position: relative;
    overflow: hidden;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
    transition: var(--transition-normal);
}

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

.btn:hover::before {
    left: 100%;
}

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

.btn-danger:hover {
    background: var(--danger-dark);
}

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

.btn-primary:hover {
    background: var(--primary-dark);
}

.btn-warning {
    background: var(--warning-color);
    color: var(--text-color);
}

.btn-warning:hover {
    background: var(--warning-dark);
}

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

.btn-success:hover {
    background: var(--success-dark);
}

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

.btn-info:hover {
    background: #138496;
}

.export-btn {
    background: var(--info-color);
    color: white;
    border: none;
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--border-radius);
    cursor: pointer;
    font-size: 1rem;
    transition: var(--transition-normal);
    font-weight: 500;
}

.export-btn:hover {
    background: #138496;
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.selection-count {
    font-weight: bold;
    color: var(--primary-color);
    margin-right: var(--spacing-md);
}

.total-rows-count {
    font-weight: bold;
    color: var(--text-light);
    margin-right: var(--spacing-md);
}

/* ==========================================================================
   الجداول
   ========================================================================== */
.preview-table-container {
    overflow: hidden;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
}

.preview-table {
    overflow-x: auto;
    max-height: 600px;
    overflow-y: auto;
}

.grades-table-container {
    overflow: hidden;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
    margin-top: var(--spacing-lg);
}

table {
    width: 100%;
    border-collapse: collapse;
    background: var(--bg-color);
    font-size: 0.875rem;
    min-width: 800px;
}

th, td {
    padding: var(--spacing-md) var(--spacing-sm);
    text-align: center;
    border-bottom: 1px solid var(--border-light);
    font-weight: 500;
}

th {
    background: var(--bg-light);
    color: var(--text-color);
    font-weight: 700;
    position: sticky;
    top: 0;
    z-index: 10;
    border-bottom: 2px solid var(--border-color);
    white-space: nowrap;
}

tr:hover {
    background: var(--bg-lighter);
}

.selectable-row {
    cursor: pointer;
    transition: var(--transition-normal);
}

.selectable-row.selected {
    background: #e3f2fd !important;
    border-right: 4px solid var(--accent-color);
}

/* ==========================================================================
   قسم النقاط
   ========================================================================== */
.grade-section {
    background: var(--bg-light);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius-lg);
    margin: var(--spacing-lg) 0;
    border: 1px solid var(--border-color);
}

.grade-controls {
    display: flex;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
    flex-wrap: wrap;
    align-items: center;
}

.grade-type-selector {
    display: flex;
    gap: var(--spacing-md);
    align-items: center;
}

.grade-type-selector label {
    font-weight: 600;
    color: var(--text-color);
}

.grade-type-selector select {
    padding: var(--spacing-sm) var(--spacing-md);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    font-family: 'Tajawal', sans-serif;
    background: var(--bg-color);
    cursor: pointer;
}

.continuous-assessment {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
    gap: var(--spacing-lg);
    margin: var(--spacing-lg) 0;
    padding: var(--spacing-lg);
    background: var(--bg-color);
    border-radius: var(--border-radius);
    border: 1px solid var(--border-light);
}

.single-grade-input {
    display: none;
    margin: var(--spacing-lg) 0;
    padding: var(--spacing-lg);
    background: var(--bg-color);
    border-radius: var(--border-radius);
    border: 1px solid var(--border-light);
}

.assessment-item {
    text-align: center;
}

.assessment-item label {
    display: block;
    margin-bottom: var(--spacing-sm);
    font-size: 0.875rem;
    color: var(--text-color);
    font-weight: 600;
}

.grade-input {
    width: 80px;
    padding: var(--spacing-sm);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    text-align: center;
    font-family: 'Tajawal', sans-serif;
    transition: var(--transition-normal);
    font-size: 1rem;
}

.grade-input:focus {
    border-color: var(--primary-color);
    outline: none;
    box-shadow: 0 0 0 2px rgba(102, 126, 234, 0.2);
}

.average-display {
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--success-color);
    margin-right: var(--spacing-sm);
}

.grade-comment {
    font-style: italic;
    color: var(--text-light);
    margin-right: var(--spacing-sm);
    font-size: 0.875rem;
}

/* ==========================================================================
   الإحصائيات
   ========================================================================== */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
    margin: var(--spacing-lg) 0;
}

.stat-card {
    background: var(--bg-color);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-md);
    text-align: center;
    border: 1px solid var(--border-color);
    transition: var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.stat-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
}

.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.stat-card.full-width {
    grid-column: 1 / -1;
}

.stat-icon {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-md);
    opacity: 0.8;
}

.stat-card h3 {
    font-size: 1.1rem;
    color: var(--text-light);
    margin-bottom: var(--spacing-md);
    font-weight: 600;
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--primary-color);
    margin: var(--spacing-sm) 0;
}

.grade-distribution {
    margin-top: var(--spacing-md);
}

.distribution-item {
    margin: var(--spacing-md) 0;
}

.distribution-header {
    display: flex;
    justify-content: space-between;
    margin-bottom: var(--spacing-sm);
}

.grade-name {
    font-weight: 500;
    color: var(--text-color);
}

.grade-count {
    color: var(--text-light);
    font-size: 0.875rem;
}

.distribution-bar {
    width: 100%;
    height: 8px;
    background: var(--border-light);
    border-radius: 4px;
    overflow: hidden;
}

.distribution-fill {
    height: 100%;
    transition: width 0.3s ease;
    border-radius: 4px;
}

.advanced-stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
}

.advanced-stat {
    background: var(--bg-light);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    border: 1px solid var(--border-light);
    text-align: center;
}

.stat-label {
    display: block;
    font-size: 0.875rem;
    color: var(--text-light);
    margin-bottom: var(--spacing-sm);
}

.stat-value {
    display: block;
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
}

/* ==========================================================================
   الإعدادات
   ========================================================================== */
.grade-settings {
    background: var(--bg-light);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius-lg);
    margin: var(--spacing-lg) 0;
    border: 1px solid var(--border-color);
}

.grade-settings h3 {
    color: var(--primary-color);
    margin-bottom: var(--spacing-md);
    font-weight: 700;
}

.settings-table-container {
    overflow-x: auto;
    margin: var(--spacing-lg) 0;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
}

.grade-settings-table {
    width: 100%;
    border-collapse: collapse;
    background: var(--bg-color);
    min-width: 600px;
}

.grade-settings-table th,
.grade-settings-table td {
    padding: var(--spacing-md) var(--spacing-sm);
    text-align: center;
    border: 1px solid var(--border-color);
}

.grade-settings-table th {
    background: var(--primary-color);
    color: white;
    font-weight: 600;
    border-color: var(--primary-dark);
}

.grade-settings-table input {
    width: 100%;
    padding: var(--spacing-sm);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    text-align: center;
    font-family: 'Tajawal', sans-serif;
    transition: var(--transition-normal);
    background: var(--bg-color);
}

.grade-settings-table input:focus {
    border-color: var(--primary-color);
    outline: none;
    box-shadow: 0 0 0 2px rgba(102, 126, 234, 0.2);
}

.import-export-section {
    background: var(--bg-light);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius-lg);
    margin: var(--spacing-lg) 0;
    border: 1px solid var(--border-color);
}

.import-export-controls {
    display: flex;
    gap: var(--spacing-md);
    align-items: center;
    flex-wrap: wrap;
    margin-bottom: var(--spacing-lg);
}

.file-input-wrapper {
    position: relative;
    display: inline-block;
}

.file-input-wrapper input[type="file"] {
    position: absolute;
    left: 0;
    top: 0;
    opacity: 0;
    width: 100%;
    height: 100%;
    cursor: pointer;
}

.file-input-label {
    display: inline-block;
    padding: var(--spacing-md) var(--spacing-lg);
    background: var(--info-color);
    color: white;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition-normal);
    font-weight: 500;
}

.file-input-label:hover {
    background: #138496;
    transform: translateY(-1px);
}

.danger-section-title {
    color: var(--danger-color);
    margin-top: var(--spacing-xl);
    margin-bottom: var(--spacing-md);
}

.danger-actions {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
    margin-bottom: var(--spacing-md);
}

.danger-warning {
    color: var(--text-light);
    font-size: 0.875rem;
    text-align: center;
    padding: var(--spacing-md);
    background: rgba(220, 53, 69, 0.05);
    border-radius: var(--border-radius);
    border: 1px solid rgba(220, 53, 69, 0.2);
}

/* ==========================================================================
   التذييل
   ========================================================================== */
.developer-footer {
    background: var(--bg-light);
    padding: var(--spacing-lg);
    text-align: center;
    border-top: 1px solid var(--border-color);
    margin-top: var(--spacing-xl);
}

.footer-content {
    max-width: 600px;
    margin: 0 auto;
}

.developer-footer p {
    margin-bottom: var(--spacing-sm);
    color: var(--text-light);
}

.developer-footer a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition-normal);
}

.developer-footer a:hover {
    color: var(--primary-dark);
    text-decoration: underline;
}

/* ==========================================================================
   مؤشر التحميل
   ========================================================================== */
.loading-spinner {
    display: none;
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: var(--bg-color);
    padding: var(--spacing-xl);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-xl);
    z-index: 1000;
    text-align: center;
    min-width: 200px;
}

.spinner {
    border: 4px solid var(--border-light);
    border-top: 4px solid var(--primary-color);
    border-radius: 50%;
    width: 50px;
    height: 50px;
    animation: spin 1s linear infinite;
    margin: 0 auto var(--spacing-md);
}

/* ==========================================================================
   الإشعارات
   ========================================================================== */
.toast-container {
    position: fixed;
    top: var(--spacing-lg);
    left: 50%;
    transform: translateX(-50%);
    z-index: 1001;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    max-width: 400px;
    width: 90%;
}

.toast {
    background: var(--success-color);
    color: white;
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-lg);
    animation: slideDown 0.3s ease;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    position: relative;
    overflow: hidden;
}

.toast::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 4px;
    background: rgba(255,255,255,0.5);
}

.toast.error {
    background: var(--danger-color);
}

.toast.warning {
    background: var(--warning-color);
    color: var(--text-color);
}

.toast.info {
    background: var(--info-color);
}

/* ==========================================================================
   الحركات والتحولات
   ========================================================================== */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

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

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

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

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

/* ==========================================================================
   التجاوب مع الأجهزة المحمولة
   ========================================================================== */
@media (max-width: 1200px) {
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-content {
        gap: var(--spacing-lg);
    }
}

@media (max-width: 992px) {
    .container {
        margin: 0;
        border-radius: 0;
    }
    
    .hero-section {
        padding: var(--spacing-lg);
    }
    
    .hero-content {
        flex-direction: column;
        text-align: center;
    }
    
    .hero-text {
        margin-bottom: var(--spacing-lg);
    }
    
    .hero-features {
        justify-content: center;
    }
    
    .hero-image {
        flex: none;
        max-width: 250px;
    }
    
    .tab-content {
        padding: var(--spacing-lg);
    }
    
    .stats-grid {
        grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
        gap: var(--spacing-md);
    }
    
    .bulk-processing-controls {
        flex-direction: column;
        align-items: center;
    }
    
    .bulk-processing-controls .btn {
        width: 100%;
        max-width: 300px;
    }
    
    .processed-sheets-list {
        grid-template-columns: 1fr;
    }
    
    .processing-summary {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    body {
        padding: var(--spacing-sm);
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1.1rem;
    }
    
    .nav-tab {
        padding: var(--spacing-md) var(--spacing-lg);
        font-size: 0.875rem;
        min-width: 120px;
    }
    
    .upload-section {
        padding: var(--spacing-lg);
    }
    
    .upload-btn {
        padding: var(--spacing-md) var(--spacing-lg);
        font-size: 0.875rem;
    }
    
    .controls {
        gap: var(--spacing-sm);
    }
    
    .search-container {
        min-width: 200px;
    }
    
    .btn, .export-btn {
        padding: var(--spacing-sm) var(--spacing-md);
        font-size: 0.813rem;
    }
    
    .grade-controls {
        gap: var(--spacing-md);
    }
    
    .continuous-assessment {
        grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
        gap: var(--spacing-md);
        padding: var(--spacing-md);
    }
    
    .stat-card {
        padding: var(--spacing-md);
    }
    
    .stat-number {
        font-size: 2rem;
    }
    
    .preview-table {
        max-height: 500px;
    }
    
    th, td {
        padding: var(--spacing-sm) var(--spacing-xs);
        font-size: 0.813rem;
    }
    
    .grade-input {
        width: 70px;
        padding: var(--spacing-xs);
    }
    
    .sheet-actions {
        flex-direction: column;
    }
    
    .sheet-action-btn {
        width: 100%;
    }
}

@media (max-width: 576px) {
    .hero-section {
        padding: var(--spacing-md);
    }
    
    .hero-title {
        font-size: 1.8rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .feature {
        font-size: 0.8rem;
        padding: var(--spacing-xs) var(--spacing-sm);
    }
    
    .nav-tabs {
        flex-wrap: nowrap;
        overflow-x: auto;
    }
    
    .nav-tab {
        min-width: 100px;
        padding: var(--spacing-md);
        font-size: 0.813rem;
    }
    
    .tab-icon {
        font-size: 1.1em;
    }
    
    .tab-content {
        padding: var(--spacing-md);
    }
    
    .upload-section {
        padding: var(--spacing-lg) var(--spacing-md);
        margin-bottom: var(--spacing-md);
    }
    
    .sheet-selector select {
        min-width: 200px;
        padding: var(--spacing-sm) var(--spacing-md);
    }
    
    .controls {
        flex-direction: column;
        align-items: stretch;
    }
    
    .search-container {
        min-width: auto;
        margin-bottom: var(--spacing-sm);
    }
    
    .bulk-selection {
        justify-content: center;
    }
    
    .bulk-btn {
        flex: 1;
        min-width: 120px;
        text-align: center;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }
    
    .continuous-assessment {
        grid-template-columns: 1fr 1fr;
    }
    
    .grade-settings-table {
        font-size: 0.813rem;
    }
    
    .grade-settings-table th,
    .grade-settings-table td {
        padding: var(--spacing-sm) var(--spacing-xs);
    }
    
    .bulk-processing-section {
        padding: var(--spacing-lg);
    }
}

@media (max-width: 380px) {
    .hero-title {
        font-size: 1.6rem;
    }
    
    .nav-tab {
        min-width: 90px;
        padding: var(--spacing-sm);
        font-size: 0.75rem;
    }
    
    .continuous-assessment {
        grid-template-columns: 1fr;
    }
    
    .feature {
        font-size: 0.75rem;
    }
    
    .sheet-stats {
        flex-direction: column;
        gap: var(--spacing-sm);
    }
}

/* ==========================================================================
   الطباعة
   ========================================================================== */
@media print {
    .nav-tabs,
    .hero-section,
    .developer-footer,
    .controls .btn:not(.export-btn),
    .bulk-processing-section {
        display: none !important;
    }
    
    .tab-content {
        display: block !important;
        padding: 0;
    }
    
    .container {
        box-shadow: none;
        border-radius: 0;
    }
    
    body {
        background: white;
    }
    
    table {
        box-shadow: none;
        border: 1px solid #000;
    }
    
    th {
        background: #f0f0f0 !important;
        color: #000 !important;
    }
}

/* ==========================================================================
   دعم الوضع عالي التباين
   ========================================================================== */
@media (prefers-contrast: high) {
    :root {
        --primary-color: #0044cc;
        --secondary-color: #663399;
        --border-color: #000000;
        --text-color: #000000;
        --bg-light: #ffffff;
    }
    
    .hero-section {
        background: linear-gradient(135deg, #0044cc 0%, #663399 100%);
    }
}

/* ==========================================================================
   دعم تقليل الحركة
   ========================================================================== */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    .stat-card:hover,
    .btn:hover,
    .upload-btn:hover,
    .sheet-card:hover {
        transform: none;
    }
}

/* ==========================================================================
   دعم الوضع المظلم
   ========================================================================== */
@media (prefers-color-scheme: dark) {
    :root {
        --text-color: #e9ecef;
        --text-light: #adb5bd;
        --bg-color: #343a40;
        --bg-light: #495057;
        --bg-lighter: #6c757d;
        --border-color: #495057;
        --border-light: #6c757d;
    }
    
    body {
        background: linear-gradient(135deg, #495057 0%, #212529 100%);
    }
    
    .container {
        background: var(--bg-color);
        color: var(--text-color);
    }
    
    .nav-tab.active {
        background: var(--bg-light);
    }
    
    .nav-tab:hover {
        background: var(--bg-light);
    }
    
    .upload-section {
        background: var(--bg-light);
        border-color: var(--border-light);
    }
    
    table {
        background: var(--bg-light);
        color: var(--text-color);
    }
    
    th {
        background: var(--bg-lighter);
        color: var(--text-color);
    }
    
    .stat-card {
        background: var(--bg-light);
        border-color: var(--border-light);
    }
    
    .grade-settings-table {
        background: var(--bg-light);
    }
    
    .bulk-processing-section {
        background: linear-gradient(135deg, #495057 0%, #6c757d 100%);
    }
    
    .sheet-card {
        background: var(--bg-lighter);
    }
}