/*
 * AI Study Planner - Premium Theme Stylesheet
 * Light Sky Blue Premium Theme
 * Developer: Mohammed Usman | GitHub: issu321
 */

/* ========== CSS VARIABLES ========== */
:root {
    /* Primary Colors - Light Sky Blue Theme */
    --primary: #3b9aed;
    --primary-light: #e8f4fd;
    --primary-dark: #1a7cd6;
    --primary-gradient: linear-gradient(135deg, #4facfe 0%, #3b9aed 50%, #1a7cd6 100%);
    --primary-gradient-soft: linear-gradient(135deg, #e8f4fd 0%, #d0eaff 100%);
    
    /* Secondary Colors */
    --secondary: #6c757d;
    --success: #10b981;
    --success-light: #d1fae5;
    --warning: #f59e0b;
    --warning-light: #fef3c7;
    --danger: #ef4444;
    --danger-light: #fee2e2;
    --info: #06b6d4;
    --info-light: #cffafe;
    
    /* Background Colors */
    --body-bg: #f0f7ff;
    --card-bg: #ffffff;
    --sidebar-bg: #ffffff;
    --navbar-bg: rgba(255, 255, 255, 0.95);
    --dropdown-bg: #ffffff;
    --hover-bg: #f0f7ff;
    --active-bg: #e8f4fd;
    
    /* Text Colors */
    --text-dark: #0f172a;
    --text-body: #334155;
    --text-muted: #64748b;
    --text-light: #94a3b8;
    
    /* Border & Shadow */
    --border-color: #e2e8f0;
    --border-light: #f1f5f9;
    --shadow-sm: 0 1px 3px rgba(59, 154, 237, 0.08);
    --shadow: 0 4px 20px rgba(59, 154, 237, 0.1);
    --shadow-lg: 0 10px 40px rgba(59, 154, 237, 0.15);
    --shadow-card: 0 2px 12px rgba(0, 0, 0, 0.06);
    
    /* Typography */
    --font-heading: 'Poppins', sans-serif;
    --font-body: 'Inter', sans-serif;
    
    /* Spacing */
    --sidebar-width: 260px;
    --navbar-height: 70px;
    --radius: 12px;
    --radius-sm: 8px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    
    /* Transitions */
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-bounce: all 0.4s cubic-bezier(0.68, -0.55, 0.265, 1.55);
}

/* ========== BASE STYLES ========== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-body);
    background: var(--body-bg);
    color: var(--text-body);
    min-height: 100vh;
    overflow-x: hidden;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    scroll-behavior: smooth;
    -webkit-tap-highlight-color: transparent;
}

/* Touch-friendly improvements */
@media (hover: none) and (pointer: coarse) {
    .menu-item:hover::before,
    .menu-item.active::before {
        opacity: 1;
    }

    .card:hover,
    .document-card:hover,
    .stat-card:hover,
    .college-card:hover,
    .feature-card:hover,
    .dev-card:hover {
        transform: none !important;
    }

    .btn-primary:hover,
    .btn-outline-primary:hover {
        transform: none !important;
    }
}

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 600;
    color: var(--text-dark);
}

a {
    text-decoration: none;
    color: var(--primary);
    transition: var(--transition);
}

a:hover {
    color: var(--primary-dark);
}

::selection {
    background: var(--primary);
    color: white;
}

/* ========== SCROLLBAR ========== */
::-webkit-scrollbar {
    width: 6px;
}

::-webkit-scrollbar-track {
    background: var(--body-bg);
}

::-webkit-scrollbar-thumb {
    background: linear-gradient(to bottom, var(--primary), var(--primary-dark));
    border-radius: 10px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--primary-dark);
}

/* ========== NAVBAR ========== */
.navbar {
    height: var(--navbar-height);
    background: var(--navbar-bg) !important;
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-color);
    padding: 0 1.5rem;
    z-index: 1040;
    transition: var(--transition);
}

/* Mobile navbar collapse fix */
.navbar-collapse {
    background: var(--navbar-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-radius: 0 0 var(--radius-lg) var(--radius-lg);
    box-shadow: var(--shadow-lg);
    padding: 1rem;
    margin-top: 0.5rem;
    border: 1px solid var(--border-color);
    border-top: none;
}

.navbar-toggler {
    border: none;
    padding: 0.5rem;
    border-radius: var(--radius-sm);
    transition: var(--transition);
}

.navbar-toggler:focus {
    box-shadow: 0 0 0 3px rgba(59, 154, 237, 0.2);
    outline: none;
}

.navbar-toggler-icon {
    width: 1.5em;
    height: 1.5em;
}

.navbar-brand {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-family: var(--font-heading);
    font-weight: 700;
    font-size: 1.4rem;
    color: var(--text-dark) !important;
}

.brand-icon {
    width: 40px;
    height: 40px;
    background: var(--primary-gradient);
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.2rem;
    box-shadow: 0 4px 15px rgba(59, 154, 237, 0.3);
    animation: float 3s ease-in-out infinite;
}

.brand-highlight {
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-5px); }
}

.nav-link {
    color: var(--text-muted) !important;
    font-weight: 500;
    padding: 0.5rem 1rem !important;
    border-radius: var(--radius-sm);
    transition: var(--transition);
    position: relative;
}

.nav-link:hover {
    color: var(--primary) !important;
    background: var(--primary-light);
}

.nav-link .badge {
    font-size: 0.65rem;
    padding: 0.25em 0.5em;
    margin-left: 0.3rem;
}

.user-dropdown {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.user-avatar-sm {
    width: 35px;
    height: 35px;
    border-radius: 50%;
    object-fit: cover;
    border: 2px solid var(--primary-light);
}

.default-avatar {
    background: var(--primary-gradient);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.75rem;
    font-weight: 600;
}

.dropdown-menu {
    border: none;
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    padding: 0.5rem;
    min-width: 200px;
}

.dropdown-item {
    padding: 0.6rem 1rem;
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
    color: var(--text-body);
    transition: var(--transition);
}

.dropdown-item:hover {
    background: var(--primary-light);
    color: var(--primary-dark);
}

/* ========== SIDEBAR ========== */
.sidebar {
    position: fixed;
    left: 0;
    top: var(--navbar-height);
    width: var(--sidebar-width);
    height: calc(100vh - var(--navbar-height));
    background: var(--sidebar-bg);
    border-right: 1px solid var(--border-color);
    z-index: 1030;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    transition: transform 0.35s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Sidebar overlay backdrop */
.sidebar-overlay {
    position: fixed;
    top: var(--navbar-height);
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(15, 23, 42, 0.4);
    backdrop-filter: blur(4px);
    z-index: 1025;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease, visibility 0.3s ease;
}

.sidebar-overlay.show {
    opacity: 1;
    visibility: visible;
}

.sidebar-header {
    padding: 1rem;
    display: flex;
    justify-content: flex-end;
}

.sidebar-toggle {
    background: none;
    border: none;
    color: var(--text-muted);
    font-size: 1.2rem;
    cursor: pointer;
    padding: 0.5rem;
}

.sidebar-menu {
    flex: 1;
    padding: 0 0.75rem;
}

.menu-section {
    margin-bottom: 1.5rem;
}

.menu-label {
    display: block;
    padding: 0.5rem 1rem;
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--text-light);
    font-weight: 600;
}

.menu-item {
    display: flex;
    align-items: center;
    padding: 0.7rem 1rem;
    color: var(--text-muted);
    font-size: 0.9rem;
    font-weight: 500;
    border-radius: var(--radius);
    margin-bottom: 0.25rem;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.menu-item::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    height: 100%;
    width: 3px;
    background: var(--primary-gradient);
    border-radius: 0 4px 4px 0;
    opacity: 0;
    transition: var(--transition);
}

.menu-item:hover {
    background: var(--primary-light);
    color: var(--primary-dark);
}

.menu-item:hover::before {
    opacity: 1;
}

.menu-item.active {
    background: var(--primary-gradient-soft);
    color: var(--primary-dark);
    font-weight: 600;
}

.menu-item.active::before {
    opacity: 1;
}

.menu-item i {
    width: 24px;
    margin-right: 0.75rem;
    font-size: 1rem;
    text-align: center;
}

.menu-item .badge {
    font-size: 0.65rem;
}

.sidebar-footer {
    padding: 1rem 0.75rem;
    border-top: 1px solid var(--border-light);
    margin-top: auto;
}

.version-info {
    text-align: center;
    padding: 0.5rem;
    color: var(--text-light);
    font-size: 0.75rem;
}

/* ========== MAIN CONTENT ========== */
.main-content {
    padding: calc(var(--navbar-height) + 1.5rem) 1.5rem 1.5rem;
    transition: var(--transition);
}

.main-content.has-sidebar {
    margin-left: var(--sidebar-width);
}

/* ========== FLASH MESSAGES ========== */
.flash-container {
    position: fixed;
    top: calc(var(--navbar-height) + 1rem);
    right: 1.5rem;
    z-index: 1050;
    max-width: 400px;
    width: 100%;
}

.flash-container .alert {
    border: none;
    border-radius: var(--radius);
    padding: 1rem 1.25rem;
    font-weight: 500;
    font-size: 0.9rem;
    animation: slideInRight 0.4s ease-out;
    backdrop-filter: blur(10px);
}

@keyframes slideInRight {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

.alert-success {
    background: rgba(16, 185, 129, 0.1);
    color: #047857;
    border-left: 4px solid var(--success);
}

.alert-danger {
    background: rgba(239, 68, 68, 0.1);
    color: #dc2626;
    border-left: 4px solid var(--danger);
}

.alert-warning {
    background: rgba(245, 158, 11, 0.1);
    color: #d97706;
    border-left: 4px solid var(--warning);
}

.alert-info {
    background: rgba(6, 182, 212, 0.1);
    color: #0891b2;
    border-left: 4px solid var(--info);
}

/* ========== CARDS ========== */
.card {
    background: var(--card-bg);
    border: none;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-card);
    transition: var(--transition);
    overflow: hidden;
}

.card:hover {
    box-shadow: var(--shadow);
}

.card-header {
    background: transparent;
    border-bottom: 1px solid var(--border-light);
    padding: 1.25rem 1.5rem;
    font-family: var(--font-heading);
    font-weight: 600;
}

.card-body {
    padding: 1.5rem;
}

.card-footer {
    background: transparent;
    border-top: 1px solid var(--border-light);
    padding: 1rem 1.5rem;
}

/* ========== STATS CARDS ========== */
.stat-card {
    background: var(--card-bg);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    box-shadow: var(--shadow-card);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.stat-card::after {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 100px;
    height: 100px;
    background: var(--primary-gradient);
    opacity: 0.05;
    border-radius: 50%;
    transform: translate(30%, -30%);
}

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

.stat-icon {
    width: 50px;
    height: 50px;
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.3rem;
    margin-bottom: 1rem;
}

.stat-icon.bg-primary-soft { background: var(--primary-light); color: var(--primary); }
.stat-icon.bg-success-soft { background: var(--success-light); color: var(--success); }
.stat-icon.bg-warning-soft { background: var(--warning-light); color: var(--warning); }
.stat-icon.bg-danger-soft { background: var(--danger-light); color: var(--danger); }
.stat-icon.bg-info-soft { background: var(--info-light); color: var(--info); }

.stat-value {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--text-dark);
    font-family: var(--font-heading);
    margin-bottom: 0.25rem;
}

.stat-label {
    font-size: 0.85rem;
    color: var(--text-muted);
    font-weight: 500;
}

.stat-trend {
    font-size: 0.8rem;
    font-weight: 600;
    margin-top: 0.5rem;
}

.stat-trend.up { color: var(--success); }
.stat-trend.down { color: var(--danger); }

/* ========== COLLEGE CARDS ========== */
.college-card {
    background: var(--card-bg);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-card);
    transition: var(--transition);
    position: relative;
}

.college-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
}

.college-card-banner {
    height: 120px;
    background: var(--primary-gradient);
    position: relative;
    overflow: hidden;
}

.college-card-banner::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.08'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
}

.college-card-logo {
    width: 70px;
    height: 70px;
    border-radius: var(--radius);
    background: white;
    padding: 5px;
    box-shadow: var(--shadow);
    position: absolute;
    bottom: -35px;
    left: 1.5rem;
    overflow: hidden;
}

.college-card-logo img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    border-radius: calc(var(--radius) - 2px);
}

.college-card-body {
    padding: 2.5rem 1.5rem 1.5rem;
}

.college-card-title {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 0.3rem;
}

.college-card-code {
    font-size: 0.75rem;
    color: var(--primary);
    font-weight: 600;
    background: var(--primary-light);
    padding: 0.2rem 0.6rem;
    border-radius: 20px;
    display: inline-block;
}

.college-card-meta {
    margin-top: 1rem;
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    font-size: 0.8rem;
    color: var(--text-muted);
}

.college-card-meta i {
    color: var(--primary);
    margin-right: 0.3rem;
}

.college-card-footer {
    padding: 1rem 1.5rem;
    border-top: 1px solid var(--border-light);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.college-status {
    padding: 0.3rem 0.8rem;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 600;
}

.status-active { background: var(--success-light); color: #047857; }
.status-inactive { background: var(--warning-light); color: #d97706; }
.status-suspended { background: var(--danger-light); color: #dc2626; }

/* ========== BUTTONS ========== */
.btn {
    font-family: var(--font-body);
    font-weight: 600;
    padding: 0.6rem 1.25rem;
    border-radius: var(--radius);
    transition: var(--transition);
    font-size: 0.9rem;
}

.btn-primary {
    background: var(--primary-gradient);
    border: none;
    color: white;
    box-shadow: 0 4px 15px rgba(59, 154, 237, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(59, 154, 237, 0.4);
    color: white;
}

.btn-outline-primary {
    border: 2px solid var(--primary);
    color: var(--primary);
    background: transparent;
}

.btn-outline-primary:hover {
    background: var(--primary-gradient);
    border-color: transparent;
    color: white;
    transform: translateY(-2px);
}

.btn-success {
    background: linear-gradient(135deg, #34d399 0%, #10b981 100%);
    border: none;
    box-shadow: 0 4px 15px rgba(16, 185, 129, 0.3);
}

.btn-danger {
    background: linear-gradient(135deg, #f87171 0%, #ef4444 100%);
    border: none;
    box-shadow: 0 4px 15px rgba(239, 68, 68, 0.3);
}

.btn-sm {
    padding: 0.4rem 0.8rem;
    font-size: 0.8rem;
}

.btn-lg {
    padding: 0.8rem 2rem;
    font-size: 1rem;
}

.btn-rounded {
    border-radius: 50px;
}

.btn-icon {
    width: 36px;
    height: 36px;
    padding: 0;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius);
}

/* ========== FORMS ========== */
.form-control, .form-select {
    border: 2px solid var(--border-color);
    border-radius: var(--radius);
    padding: 0.65rem 1rem;
    font-size: 0.9rem;
    font-family: var(--font-body);
    transition: var(--transition);
    background: var(--card-bg);
}

.form-control:focus, .form-select:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 4px rgba(59, 154, 237, 0.15);
    background: var(--card-bg);
}

.form-label {
    font-weight: 600;
    font-size: 0.85rem;
    color: var(--text-dark);
    margin-bottom: 0.4rem;
}

.input-group-text {
    background: var(--primary-light);
    border: 2px solid var(--border-color);
    border-right: none;
    color: var(--primary);
    font-weight: 500;
}

/* ========== TABLES ========== */
.table-container {
    background: var(--card-bg);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-card);
    overflow: hidden;
}

.table {
    margin-bottom: 0;
    font-size: 0.9rem;
}

.table thead th {
    background: var(--primary-light);
    color: var(--primary-dark);
    font-weight: 600;
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    border: none;
    padding: 1rem 1.25rem;
}

.table tbody td {
    padding: 1rem 1.25rem;
    vertical-align: middle;
    border-bottom: 1px solid var(--border-light);
}

.table tbody tr {
    transition: var(--transition);
}

.table tbody tr:hover {
    background: var(--primary-light);
}

.table tbody tr:last-child td {
    border-bottom: none;
}

/* ========== BADGES ========== */
.badge {
    padding: 0.4em 0.7em;
    font-weight: 600;
    font-size: 0.75rem;
    border-radius: 6px;
    transition: transform 0.2s ease;
}

.badge:hover {
    transform: scale(1.1);
}

/* Notification badge pulse animation */
.nav-link .badge.bg-danger,
.menu-item .badge.bg-danger {
    animation: badgePulse 2s ease-in-out infinite;
}

@keyframes badgePulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.15); }
}

/* Toast notification style */
.toast-notification {
    position: fixed;
    top: calc(var(--navbar-height) + 1rem);
    right: 1.5rem;
    z-index: 1050;
    max-width: 400px;
    width: 100%;
    background: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    padding: 1rem 1.25rem;
    border-left: 4px solid var(--primary);
    animation: toastSlideIn 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.toast-notification.success { border-left-color: var(--success); }
.toast-notification.error { border-left-color: var(--danger); }
.toast-notification.warning { border-left-color: var(--warning); }
.toast-notification.info { border-left-color: var(--info); }

@keyframes toastSlideIn {
    from {
        transform: translateX(120%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

@keyframes toastSlideOut {
    from {
        transform: translateX(0);
        opacity: 1;
    }
    to {
        transform: translateX(120%);
        opacity: 0;
    }
}

.bg-gradient {
    background: var(--primary-gradient) !important;
}

.badge-subject {
    background: var(--primary-light);
    color: var(--primary-dark);
    padding: 0.3rem 0.8rem;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
}

/* ========== PAGINATION ========== */
.pagination {
    gap: 0.3rem;
}

.page-link {
    border: none;
    border-radius: var(--radius-sm) !important;
    color: var(--text-muted);
    font-weight: 500;
    padding: 0.5rem 0.9rem;
    transition: var(--transition);
}

.page-link:hover {
    background: var(--primary-light);
    color: var(--primary);
}

.page-item.active .page-link {
    background: var(--primary-gradient);
    color: white;
    box-shadow: 0 4px 10px rgba(59, 154, 237, 0.3);
}

/* ========== MODALS ========== */
.modal-content {
    border: none;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
}

.modal-header {
    border-bottom: 1px solid var(--border-light);
    padding: 1.25rem 1.5rem;
}

.modal-footer {
    border-top: 1px solid var(--border-light);
    padding: 1rem 1.5rem;
}

/* ========== TABS ========== */
.nav-tabs {
    border-bottom: 2px solid var(--border-color);
    gap: 0.5rem;
}

.nav-tabs .nav-link {
    border: none;
    color: var(--text-muted);
    font-weight: 600;
    padding: 0.75rem 1.25rem !important;
    border-radius: var(--radius-sm) var(--radius-sm) 0 0 !important;
    position: relative;
}

.nav-tabs .nav-link::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--primary-gradient);
    transform: scaleX(0);
    transition: var(--transition);
}

.nav-tabs .nav-link:hover {
    color: var(--primary);
    background: transparent;
}

.nav-tabs .nav-link.active {
    color: var(--primary);
    background: transparent;
}

.nav-tabs .nav-link.active::after {
    transform: scaleX(1);
}

/* ========== PROGRESS BARS ========== */
.progress {
    height: 8px;
    background: var(--border-light);
    border-radius: 10px;
    overflow: hidden;
}

.progress-bar {
    background: var(--primary-gradient);
    border-radius: 10px;
    transition: width 0.6s ease;
}

.progress-bar-success { background: linear-gradient(90deg, #34d399, #10b981); }
.progress-bar-warning { background: linear-gradient(90deg, #fbbf24, #f59e0b); }
.progress-bar-danger { background: linear-gradient(90deg, #f87171, #ef4444); }

/* ========== EMPTY STATE ========== */
.empty-state {
    text-align: center;
    padding: 3rem 2rem;
}

.empty-state-icon {
    width: 100px;
    height: 100px;
    background: var(--primary-light);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
    font-size: 2.5rem;
    color: var(--primary);
}

.empty-state-title {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 0.5rem;
}

.empty-state-text {
    color: var(--text-muted);
    font-size: 0.9rem;
    max-width: 400px;
    margin: 0 auto 1.5rem;
}

/* ========== TIMELINE ========== */
.timeline {
    position: relative;
    padding-left: 2rem;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 8px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--primary-light);
}

.timeline-item {
    position: relative;
    padding-bottom: 1.5rem;
}

.timeline-dot {
    position: absolute;
    left: -2rem;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--primary-gradient);
    border: 3px solid white;
    box-shadow: var(--shadow-sm);
}

.timeline-content {
    background: var(--card-bg);
    padding: 1rem 1.25rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow-sm);
    font-size: 0.9rem;
}

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

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

@keyframes slideInLeft {
    from {
        opacity: 0;
        transform: translateX(-30px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.animate-fade-in {
    animation: fadeInUp 0.5s ease-out;
}

.animate-scale-in {
    animation: scaleIn 0.4s ease-out;
}

/* ========== FOOTER ========== */
.app-footer {
    background: white;
    border-top: 1px solid var(--border-color);
    padding: 1.25rem 1.5rem;
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-top: 2rem;
}

.main-content.has-sidebar + .app-footer {
    margin-left: var(--sidebar-width);
}

/* ========== LANDING PAGE ========== */
.hero-section {
    background: var(--primary-gradient);
    color: white;
    padding: 6rem 0 5rem;
    position: relative;
    overflow: hidden;
}

.hero-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.08'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
}

.hero-title {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: 1rem;
    position: relative;
}

.hero-subtitle {
    font-size: 1.2rem;
    opacity: 0.9;
    margin-bottom: 2rem;
    max-width: 500px;
}

.hero-image {
    position: relative;
    animation: float 6s ease-in-out infinite;
}

.feature-card {
    background: var(--card-bg);
    border-radius: var(--radius-lg);
    padding: 2rem;
    text-align: center;
    box-shadow: var(--shadow-card);
    transition: var(--transition);
    border: 1px solid var(--border-light);
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-light);
}

.feature-icon {
    width: 70px;
    height: 70px;
    border-radius: var(--radius);
    background: var(--primary-light);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
    font-size: 1.8rem;
    color: var(--primary);
    transition: var(--transition);
}

.feature-card:hover .feature-icon {
    background: var(--primary-gradient);
    color: white;
    transform: scale(1.1);
}

/* ========== LOGIN & REGISTER ========== */
.auth-wrapper {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--body-bg);
    padding: 2rem;
    position: relative;
}

.auth-wrapper::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 800px;
    height: 800px;
    background: var(--primary-gradient);
    opacity: 0.05;
    border-radius: 50%;
}

.auth-card {
    background: var(--card-bg);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-lg);
    padding: 2.5rem;
    width: 100%;
    max-width: 450px;
    position: relative;
    z-index: 1;
}

.auth-header {
    text-align: center;
    margin-bottom: 2rem;
}

.auth-logo {
    width: 60px;
    height: 60px;
    background: var(--primary-gradient);
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1rem;
    color: white;
    font-size: 1.5rem;
    box-shadow: 0 8px 25px rgba(59, 154, 237, 0.3);
}

.auth-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 0.3rem;
}

.auth-subtitle {
    color: var(--text-muted);
    font-size: 0.9rem;
}

.auth-footer {
    text-align: center;
    margin-top: 1.5rem;
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* ========== DEVELOPER PAGE ========== */
.dev-hero {
    background: var(--primary-gradient);
    color: white;
    padding: 4rem 0;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.dev-avatar {
    width: 120px;
    height: 120px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
    font-size: 3rem;
    border: 4px solid rgba(255, 255, 255, 0.3);
}

.dev-name {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.dev-role {
    font-size: 1rem;
    opacity: 0.9;
    margin-bottom: 1.5rem;
}

.dev-social-links {
    display: flex;
    justify-content: center;
    gap: 1rem;
}

.dev-social-links a {
    width: 45px;
    height: 45px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.2rem;
    transition: var(--transition);
}

.dev-social-links a:hover {
    background: white;
    color: var(--primary);
    transform: translateY(-3px);
}

.dev-section {
    padding: 3rem 0;
}

.dev-card {
    background: var(--card-bg);
    border-radius: var(--radius-lg);
    padding: 2rem;
    box-shadow: var(--shadow-card);
    height: 100%;
    transition: var(--transition);
    border: 1px solid var(--border-light);
}

.dev-card:hover {
    box-shadow: var(--shadow);
    transform: translateY(-3px);
}

.dev-icon {
    width: 50px;
    height: 50px;
    background: var(--primary-light);
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary);
    font-size: 1.3rem;
    margin-bottom: 1rem;
}

/* ========== STUDY PLANNER ========== */
.planner-header {
    background: var(--primary-gradient);
    color: white;
    padding: 2rem;
    border-radius: var(--radius-lg);
    margin-bottom: 2rem;
    position: relative;
    overflow: hidden;
}

.planner-header::before {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 200px;
    height: 200px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    transform: translate(50%, -50%);
}

.schedule-day {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 1.25rem;
    margin-bottom: 1rem;
    box-shadow: var(--shadow-sm);
    border-left: 4px solid var(--primary);
}

.schedule-session {
    background: var(--primary-light);
    border-radius: var(--radius-sm);
    padding: 0.75rem 1rem;
    margin-top: 0.5rem;
    font-size: 0.9rem;
}

.recommendation-card {
    border-radius: var(--radius);
    padding: 1rem 1.25rem;
    margin-bottom: 0.75rem;
    font-size: 0.9rem;
    border-left: 4px solid;
}

.recommendation-card.warning {
    background: var(--warning-light);
    border-color: var(--warning);
    color: #92400e;
}

.recommendation-card.urgent {
    background: var(--danger-light);
    border-color: var(--danger);
    color: #991b1b;
}

.recommendation-card.info {
    background: var(--info-light);
    border-color: var(--info);
    color: #155e75;
}

.recommendation-card.success {
    background: var(--success-light);
    border-color: var(--success);
    color: #065f46;
}

.recommendation-card.tip {
    background: #f3e8ff;
    border-color: #a855f7;
    color: #6b21a8;
}

/* ========== TEST TAKING ========== */
.test-container {
    background: var(--card-bg);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow);
    padding: 2rem;
    max-width: 800px;
    margin: 0 auto;
}

.test-timer {
    position: fixed;
    top: var(--navbar-height);
    right: 2rem;
    background: var(--danger);
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: 0 0 var(--radius) var(--radius);
    font-weight: 700;
    font-size: 1.1rem;
    z-index: 1020;
    box-shadow: 0 4px 15px rgba(239, 68, 68, 0.3);
}

.question-card {
    background: var(--body-bg);
    border-radius: var(--radius);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
}

.question-number {
    display: inline-block;
    width: 32px;
    height: 32px;
    background: var(--primary-gradient);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 0.85rem;
    margin-right: 0.75rem;
    flex-shrink: 0;
}

.option-label {
    display: flex;
    align-items: center;
    padding: 0.75rem 1rem;
    background: var(--card-bg);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-sm);
    margin-bottom: 0.5rem;
    cursor: pointer;
    transition: var(--transition);
}

.option-label:hover {
    border-color: var(--primary-light);
    background: var(--primary-light);
}

.option-label input[type="radio"] {
    margin-right: 0.75rem;
}

/* ========== RESPONSIVE ========== */
@media (max-width: 991px) {
    .sidebar {
        transform: translateX(-100%);
        z-index: 1060;
    }
    
    .sidebar.show {
        transform: translateX(0);
    }
    
    .main-content.has-sidebar {
        margin-left: 0;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .main-content.has-sidebar + .app-footer {
        margin-left: 0;
    }
}

@media (max-width: 768px) {
    .hero-section {
        padding: 4rem 0 3rem;
    }
    
    .hero-title {
        font-size: 1.75rem;
    }
    
    .stat-card {
        margin-bottom: 1rem;
    }
    
    .flash-container {
        left: 1rem;
        right: 1rem;
        max-width: none;
    }
}

/* ========== PRINT ========== */
@media print {
    .sidebar, .navbar, .app-footer, .btn {
        display: none !important;
    }
    
    .main-content {
        margin-left: 0 !important;
        padding: 0 !important;
    }
}

/* ========== MISCELLANEOUS ========== */
.text-gradient {
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.bg-soft { background: var(--primary-light); }
.border-soft { border-color: var(--border-light); }

.page-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 0.25rem;
}

.page-subtitle {
    color: var(--text-muted);
    font-size: 0.9rem;
}

.section-title {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.search-box {
    position: relative;
}

.search-box i {
    position: absolute;
    left: 1rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-light);
}

.search-box input {
    padding-left: 2.5rem;
    border-radius: 50px;
}

.divider {
    height: 1px;
    background: var(--border-light);
    margin: 1.5rem 0;
}

.avatar-lg {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    object-fit: cover;
    border: 3px solid var(--primary-light);
}

.avatar-md {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    object-fit: cover;
}

.hover-scale {
    transition: var(--transition);
}

.hover-scale:hover {
    transform: scale(1.05);
}

.document-card {
    display: flex;
    align-items: center;
    padding: 1rem;
    background: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    border: 1px solid var(--border-light);
}

.document-card:hover {
    box-shadow: var(--shadow);
}

.document-icon {
    width: 45px;
    height: 45px;
    border-radius: var(--radius-sm);
    background: var(--primary-light);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary);
    font-size: 1.2rem;
    margin-right: 1rem;
    flex-shrink: 0;
}

.chart-container {
    position: relative;
    height: 300px;
    width: 100%;
}

.info-row {
    display: flex;
    padding: 0.75rem 0;
    border-bottom: 1px solid var(--border-light);
}

.info-row:last-child {
    border-bottom: none;
}

.info-label {
    width: 140px;
    font-weight: 600;
    color: var(--text-muted);
    font-size: 0.85rem;
    flex-shrink: 0;
}

.info-value {
    color: var(--text-dark);
    font-size: 0.9rem;
}
/* Premium loading skeleton */
.skeleton {
    background: linear-gradient(90deg, var(--border-light) 25%, var(--body-bg) 50%, var(--border-light) 75%);
    background-size: 200% 100%;
    animation: skeletonShimmer 1.5s ease-in-out infinite;
    border-radius: var(--radius-sm);
}

@keyframes skeletonShimmer {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}

/* Premium glass morphism effect */
.glass {
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.3);
}

/* Premium hover lift with shadow */
.hover-lift {
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1), box-shadow 0.3s ease;
}

.hover-lift:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

/* Smooth page transitions */
.page-transition {
    animation: pageFadeIn 0.4s ease-out;
}

@keyframes pageFadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}