/* Umeed Bihar Learning App - Complete Styles */

:root {
    /* Colors */
    --primary: #667eea;
    --primary-hover: #5a6fd8;
    --secondary: #764ba2;
    --success: #28a745;
    --warning: #ffc107;
    --danger: #dc3545;
    --info: #17a2b8;
    --light: #f8f9fa;
    --dark: #343a40;
    --white: #ffffff;
    --gray-100: #f8f9fa;
    --gray-200: #e9ecef;
    --gray-300: #dee2e6;
    --gray-400: #ced4da;
    --gray-500: #adb5bd;
    --gray-600: #6c757d;
    --gray-700: #495057;
    --gray-800: #343a40;
    --gray-900: #212529;
    
    /* Spacing */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-5: 1.25rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-10: 2.5rem;
    --space-12: 3rem;
    
    /* Border radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.375rem;
    --radius-lg: 0.5rem;
    --radius-xl: 0.75rem;
    --radius-2xl: 1rem;
    --radius-full: 9999px;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

/* Base Styles */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html, body {
    height: 100%;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    font-size: 14px;
    line-height: 1.5;
    color: var(--gray-900);
    background-color: var(--gray-100);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Screen Management */
.screen {
    display: none;
}

.screen.active {
    display: block;
}

/* Login Screen */
.login-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    padding: var(--space-4);
}

.login-card {
    background: var(--white);
    border-radius: var(--radius-2xl);
    padding: var(--space-8);
    box-shadow: var(--shadow-xl);
    width: 100%;
    max-width: 400px;
}

.login-header {
    text-align: center;
    margin-bottom: var(--space-8);
}

.login-header h1 {
    font-size: 2rem;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: var(--space-2);
}

.login-header p {
    color: var(--gray-600);
    font-size: 1rem;
}

.login-form {
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
}

.form-group {
    margin-bottom: var(--space-4);
}

.form-label {
    display: block;
    margin-bottom: var(--space-2);
    font-weight: 500;
    color: var(--gray-700);
    font-size: 0.875rem;
}

.form-control {
    display: block;
    width: 100%;
    padding: var(--space-3);
    font-size: 1rem;
    line-height: 1.5;
    color: var(--gray-900);
    background-color: var(--white);
    border: 2px solid var(--gray-300);
    border-radius: var(--radius-lg);
    transition: border-color 0.15s ease-in-out, box-shadow 0.15s ease-in-out;
}

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

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-3) var(--space-4);
    margin-bottom: 0;
    font-size: 1rem;
    font-weight: 500;
    line-height: 1.5;
    text-align: center;
    text-decoration: none;
    vertical-align: middle;
    cursor: pointer;
    border: 1px solid transparent;
    border-radius: var(--radius-lg);
    transition: all 0.15s ease-in-out;
}

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

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

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

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

.btn--sm {
    padding: var(--space-2) var(--space-3);
    font-size: 0.875rem;
}

.btn--full-width {
    width: 100%;
}

.login-help {
    margin-top: var(--space-6);
    padding-top: var(--space-4);
    border-top: 1px solid var(--gray-200);
    text-align: center;
    font-size: 0.875rem;
    color: var(--gray-600);
}

.login-help p {
    margin: var(--space-1) 0;
}

/* Dashboard Layout */
.dashboard-layout {
    display: grid;
    grid-template-areas:
        "header header"
        "sidebar main";
    grid-template-columns: 280px 1fr;
    grid-template-rows: auto 1fr;
    min-height: 100vh;
    background-color: var(--gray-100);
}

.dashboard-header {
    grid-area: header;
    background: var(--white);
    border-bottom: 1px solid var(--gray-200);
    padding: var(--space-4) var(--space-6);
    box-shadow: var(--shadow-sm);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1400px;
    margin: 0 auto;
}

.header-content h1 {
    color: var(--primary);
    font-size: 1.5rem;
    font-weight: 600;
}

.user-info {
    display: flex;
    align-items: center;
    gap: var(--space-4);
    font-size: 0.875rem;
    color: var(--gray-600);
}

.dashboard-sidebar {
    grid-area: sidebar;
    background: var(--white);
    border-right: 1px solid var(--gray-200);
    padding: var(--space-6);
    overflow-y: auto;
}

.sidebar-section {
    margin-bottom: var(--space-8);
}

.sidebar-section h3 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--gray-900);
    margin-bottom: var(--space-4);
}

.subject-list {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}

.subject-item, .nav-link {
    display: flex;
    align-items: center;
    padding: var(--space-3) var(--space-4);
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: background-color 0.15s ease-in-out;
    text-decoration: none;
    color: var(--gray-700);
    font-weight: 500;
}

.subject-item:hover, .nav-link:hover {
    background-color: var(--gray-100);
    color: var(--gray-900);
}

.subject-item.active, .nav-link.active {
    background-color: var(--primary);
    color: var(--white);
}

.dashboard-main {
    grid-area: main;
    padding: var(--space-6);
    overflow-y: auto;
    background: var(--gray-100);
}

/* Content Sections */
.content-section {
    display: none;
    max-width: 1200px;
    margin: 0 auto;
}

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

.section-header {
    display: flex;
    align-items: center;
    gap: var(--space-4);
    margin-bottom: var(--space-6);
}

.section-header h2 {
    color: var(--gray-900);
    font-size: 1.75rem;
    font-weight: 600;
}

/* Stats Grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--space-6);
    margin-bottom: var(--space-8);
}

.stat-card {
    background: var(--white);
    border-radius: var(--radius-2xl);
    padding: var(--space-6);
    display: flex;
    align-items: center;
    gap: var(--space-4);
    box-shadow: var(--shadow-md);
    transition: transform 0.2s ease-in-out, box-shadow 0.2s ease-in-out;
}

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

.stat-icon {
    font-size: 2.5rem;
    line-height: 1;
}

.stat-content h3 {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: var(--space-1);
}

.stat-content p {
    color: var(--gray-600);
    margin: 0;
    font-size: 0.875rem;
    font-weight: 500;
}

/* Subjects Grid */
.subjects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--space-6);
}

.subject-card {
    background: var(--white);
    border-radius: var(--radius-2xl);
    padding: var(--space-6);
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
    box-shadow: var(--shadow-md);
}

.subject-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
}

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

.subject-header {
    display: flex;
    align-items: center;
    gap: var(--space-4);
    margin-bottom: var(--space-4);
}

.subject-header .subject-icon {
    font-size: 2.5rem;
    line-height: 1;
}

.subject-header h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--gray-900);
}

.subject-progress {
    margin-bottom: var(--space-4);
    text-align: center;
}

.progress-circle {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--primary);
    margin: 0 auto var(--space-3);
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1), rgba(118, 75, 162, 0.1));
    border: 3px solid rgba(102, 126, 234, 0.2);
}

.subject-stats {
    display: flex;
    justify-content: space-between;
    font-size: 0.875rem;
    color: var(--gray-600);
    font-weight: 500;
}

/* Subject Content Layout */
.subject-content {
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: var(--space-6);
    min-height: 600px;
}

.folders-sidebar {
    background: var(--white);
    border-radius: var(--radius-2xl);
    padding: var(--space-5);
    box-shadow: var(--shadow-md);
    height: fit-content;
}

.folders-sidebar h3 {
    color: var(--gray-900);
    font-weight: 600;
    margin-bottom: var(--space-4);
}

.folders-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}

.folder-item {
    padding: var(--space-3) var(--space-4);
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: background-color 0.15s ease-in-out;
    color: var(--gray-700);
    font-weight: 500;
}

.folder-item:hover {
    background-color: var(--gray-100);
}

.folder-item.active {
    background-color: var(--primary);
    color: var(--white);
}

.content-area {
    background: var(--white);
    border-radius: var(--radius-2xl);
    overflow: hidden;
    box-shadow: var(--shadow-md);
}

/* Tabs */
.content-tabs {
    display: flex;
    border-bottom: 1px solid var(--gray-200);
}

.tab-btn {
    padding: var(--space-4) var(--space-6);
    border: none;
    background: none;
    color: var(--gray-600);
    cursor: pointer;
    font-weight: 500;
    transition: all 0.15s ease-in-out;
    border-bottom: 2px solid transparent;
}

.tab-btn:hover {
    background-color: var(--gray-50);
    color: var(--gray-900);
}

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

.tab-content {
    position: relative;
}

.tab-pane {
    display: none;
    padding: var(--space-6);
}

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

/* Lectures and Notes Lists */
.lectures-list, .notes-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
}

.lecture-item, .note-item {
    display: flex;
    align-items: center;
    gap: var(--space-4);
    padding: var(--space-4);
    border: 1px solid var(--gray-200);
    border-radius: var(--radius-xl);
    transition: all 0.2s ease-in-out;
    background: var(--gray-50);
}

.lecture-item:hover, .note-item:hover {
    border-color: var(--primary);
    background: var(--white);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.lecture-item.completed {
    border-color: var(--success);
    background: rgba(40, 167, 69, 0.05);
}

.lecture-status, .note-status {
    font-size: 1.5rem;
    line-height: 1;
}

.lecture-status.completed {
    color: var(--success);
}

.lecture-info, .note-info {
    flex: 1;
}

.lecture-info h4, .note-info h4 {
    color: var(--gray-900);
    font-weight: 600;
    margin-bottom: var(--space-1);
}

.lecture-meta, .note-meta {
    font-size: 0.875rem;
    color: var(--gray-600);
}

.lecture-progress {
    min-width: 80px;
    text-align: right;
}

.progress-bar {
    background: var(--gray-200);
    height: 6px;
    border-radius: var(--radius-full);
    overflow: hidden;
    margin-bottom: var(--space-1);
}

.progress-fill {
    background: var(--primary);
    height: 100%;
    transition: width 0.3s ease-in-out;
    border-radius: var(--radius-full);
}

.progress-text {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--primary);
}

.action-btn {
    padding: var(--space-2) var(--space-4);
    border-radius: var(--radius-lg);
    border: 1px solid var(--primary);
    background: var(--primary);
    color: var(--white);
    cursor: pointer;
    transition: all 0.15s ease-in-out;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    font-size: 0.875rem;
    font-weight: 500;
}

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

.empty-state {
    text-align: center;
    color: var(--gray-500);
    font-style: italic;
    padding: var(--space-8);
}

/* Video Player Modal */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.modal.hidden {
    display: none;
}

.modal-content {
    background: var(--white);
    border-radius: var(--radius-2xl);
    width: 90%;
    max-width: 800px;
    max-height: 80vh;
    overflow: hidden;
    position: relative;
    box-shadow: var(--shadow-xl);
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--space-5);
    border-bottom: 1px solid var(--gray-200);
}

.modal-header h3 {
    color: var(--gray-900);
    font-weight: 600;
    margin: 0;
}

.modal-close {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--gray-500);
    padding: var(--space-1);
    border-radius: var(--radius-md);
    transition: color 0.15s ease-in-out;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-close:hover {
    color: var(--gray-900);
    background-color: var(--gray-100);
}

.modal-body {
    padding: var(--space-6);
}

.video-wrapper {
    background: var(--gray-900);
    border-radius: var(--radius-xl);
    overflow: hidden;
    margin-bottom: var(--space-4);
    position: relative;
}

.video-frame {
    position: relative;
    width: 100%;
    aspect-ratio: 16/9;
    background: #000;
    display: flex;
    align-items: center;
    justify-content: center;
}

.video-frame iframe {
    width: 100%;
    height: 100%;
    border: none;
}

#fullScreenBtn {
    position: absolute;
    bottom: var(--space-4);
    right: var(--space-4);
    z-index: 10;
    opacity: 0.9;
    font-size: 0.875rem;
    padding: var(--space-2) var(--space-3);
    background: rgba(0, 0, 0, 0.7);
    border: none;
    color: var(--white);
    border-radius: var(--radius-md);
}

.video-info {
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
}

.video-progress-info {
    display: flex;
    align-items: center;
    gap: var(--space-3);
}

.video-progress-info .progress-bar {
    flex: 1;
    height: 8px;
}

#videoProgressText {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--primary);
    min-width: 40px;
}

/* Responsive Design */
@media (max-width: 768px) {
    .dashboard-layout {
        grid-template-areas:
            "header"
            "main";
        grid-template-columns: 1fr;
        grid-template-rows: auto 1fr;
    }

    .dashboard-sidebar {
        display: none;
    }

    .dashboard-main {
        padding: var(--space-4);
    }

    .stats-grid {
        grid-template-columns: 1fr;
    }

    .subjects-grid {
        grid-template-columns: 1fr;
    }

    .subject-content {
        grid-template-columns: 1fr;
    }

    .folders-sidebar {
        order: 2;
        margin-top: var(--space-4);
    }

    .content-area {
        order: 1;
    }

    .modal-content {
        width: 95%;
        margin: var(--space-4);
    }

    .video-frame {
        aspect-ratio: 16/9;
        min-height: 200px;
    }
}

@media (max-width: 480px) {
    .login-container {
        padding: var(--space-4);
    }

    .login-card {
        padding: var(--space-6);
    }

    .dashboard-main {
        padding: var(--space-3);
    }

    .section-header {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--space-3);
    }

    .modal-body {
        padding: var(--space-4);
    }

    .video-frame {
        min-height: 180px;
    }
}

/* Dark mode support */
@media (prefers-color-scheme: dark) {
    :root {
        --white: #1a1a1a;
        --gray-100: #111111;
        --gray-200: #2a2a2a;
        --gray-300: #3a3a3a;
        --gray-400: #4a4a4a;
        --gray-500: #6a6a6a;
        --gray-600: #8a8a8a;
        --gray-700: #aaaaaa;
        --gray-800: #cccccc;
        --gray-900: #ffffff;
    }
    
    body {
        background-color: var(--gray-100);
        color: var(--gray-900);
    }
}
.back-btn {
    background: none;
    border: none;
    font-size: 2rem;
    color: #667eea;
    cursor: pointer;
    margin-right: 1rem;
    line-height: 1;
    padding: 0 8px;
    transition: color .2s;
    display: none;
}
.back-btn:hover {
    color: #764ba2;
}