:root {
    --primary-blue: #1e40af;
    --primary-blue-dark: #1e3a8a;
    --primary-blue-light: #3b82f6;
    --accent-green: #10b981;
    --accent-orange: #f59e0b;
    --accent-red: #ef4444;
    --accent-purple: #8b5cf6;
    --text-dark: #1f2937;
    --text-muted: #6b7280;
    --text-light: #9ca3af;
    --bg-light: #f8fafc;
    --bg-white: #ffffff;
    --border-color: #e5e7eb;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --transition-fast: 150ms ease-in-out;
    --transition-normal: 300ms ease-in-out;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    color: var(--text-dark);
    line-height: 1.6;
    background-color: var(--bg-light);
}

.navbar {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    padding: 0.75rem 0;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    transition: var(--transition-normal);
}

.navbar.scrolled {
    box-shadow: var(--shadow-md);
}

.navbar-brand {
    font-weight: 700;
    font-size: 1.5rem;
    color: var(--primary-blue) !important;
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.navbar-brand span {
    background: linear-gradient(135deg, var(--primary-blue), var(--primary-blue-light));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-link {
    color: var(--text-dark) !important;
    font-weight: 500;
    padding: 0.5rem 1rem !important;
    border-radius: var(--radius-md);
    transition: var(--transition-fast);
}

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

.hero-section {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    padding-top: 80px;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, rgba(30, 64, 175, 0.9) 0%, rgba(59, 130, 246, 0.85) 50%, rgba(30, 58, 138, 0.9) 100%);
}

.hero-content {
    position: relative;
    z-index: 10;
    text-align: center;
    color: white;
    max-width: 800px;
    padding: 2rem;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
    line-height: 1.2;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
}

.hero-tagline {
    font-size: 1.5rem;
    font-weight: 300;
    margin-bottom: 2rem;
    opacity: 0.95;
    letter-spacing: 0.5px;
}

.hero-subtitle {
    font-size: 1.125rem;
    opacity: 0.9;
    margin-bottom: 2.5rem;
    line-height: 1.8;
}

.btn-hero {
    display: inline-flex;
    align-items: center;
    gap: 0.75rem;
    background: white;
    color: var(--primary-blue);
    padding: 1rem 2.5rem;
    font-size: 1.125rem;
    font-weight: 600;
    border-radius: 50px;
    text-decoration: none;
    transition: var(--transition-normal);
    box-shadow: var(--shadow-lg);
}

.btn-hero:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-xl);
    color: var(--primary-blue-dark);
}

.btn-hero i {
    font-size: 1.25rem;
}

.btn-primary-modern {
    background: linear-gradient(135deg, var(--primary-blue), var(--primary-blue-light));
    border: none;
    color: white;
    padding: 0.75rem 1.5rem;
    font-weight: 600;
    border-radius: var(--radius-md);
    transition: var(--transition-fast);
    box-shadow: var(--shadow-sm);
}

.btn-primary-modern:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
    background: linear-gradient(135deg, var(--primary-blue-dark), var(--primary-blue));
}

.btn-outline-modern {
    background: transparent;
    border: 2px solid var(--primary-blue);
    color: var(--primary-blue);
    padding: 0.75rem 1.5rem;
    font-weight: 600;
    border-radius: var(--radius-md);
    transition: var(--transition-fast);
}

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

.stats-section {
    background: white;
    padding: 4rem 0;
    border-bottom: 1px solid var(--border-color);
}

.stat-card {
    text-align: center;
    padding: 2rem;
}

.stat-number {
    font-size: 3rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--primary-blue), var(--accent-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 0.5rem;
}

.stat-label {
    color: var(--text-muted);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 1px;
    font-size: 0.875rem;
}

.features-section {
    padding: 5rem 0;
    background: var(--bg-light);
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 1rem;
    color: var(--text-dark);
}

.section-subtitle {
    text-align: center;
    color: var(--text-muted);
    font-size: 1.125rem;
    margin-bottom: 3rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.feature-card {
    background: white;
    border-radius: var(--radius-xl);
    padding: 2rem;
    height: 100%;
    border: 1px solid var(--border-color);
    transition: var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-blue), var(--primary-blue-light));
    transform: scaleX(0);
    transition: var(--transition-normal);
}

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

.feature-card:hover::before {
    transform: scaleX(1);
}

.feature-icon {
    width: 60px;
    height: 60px;
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
}

.feature-icon.blue {
    background: rgba(59, 130, 246, 0.1);
    color: var(--primary-blue-light);
}

.feature-icon.green {
    background: rgba(16, 185, 129, 0.1);
    color: var(--accent-green);
}

.feature-icon.orange {
    background: rgba(245, 158, 11, 0.1);
    color: var(--accent-orange);
}

.feature-icon.purple {
    background: rgba(139, 92, 246, 0.1);
    color: var(--accent-purple);
}

.feature-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
    color: var(--text-dark);
}

.feature-desc {
    color: var(--text-muted);
    font-size: 0.95rem;
    line-height: 1.7;
}

.dashboard-container {
    padding-top: 80px;
    padding-bottom: 5rem;
    min-height: calc(100vh - 200px);
    background: var(--bg-light);
}

.dashboard-header {
    background: linear-gradient(135deg, var(--primary-blue), var(--primary-blue-light));
    color: white;
    padding: 2rem 0;
    margin-bottom: 2rem;
}

.dashboard-title {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: 0.25rem;
}

.dashboard-subtitle {
    opacity: 0.9;
    font-size: 1rem;
}

.dashboard-card {
    background: white;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
    overflow: hidden;
    transition: var(--transition-fast);
    margin-bottom: 1rem;
}

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

.dashboard-card-header {
    padding: 1.25rem 1.5rem;
    border-bottom: 1px solid var(--border-color);
    background: var(--bg-light);
}

.dashboard-card-title {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-dark);
    margin: 0;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.dashboard-card-body {
    padding: 1.5rem;
}

.stat-widget {
    background: white;
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    border: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    gap: 1rem;
    transition: var(--transition-fast);
}

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

.stat-widget-icon {
    width: 56px;
    height: 56px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
}

.stat-widget-icon.blue {
    background: rgba(59, 130, 246, 0.1);
    color: var(--primary-blue-light);
}

.stat-widget-icon.green {
    background: rgba(16, 185, 129, 0.1);
    color: var(--accent-green);
}

.stat-widget-icon.orange {
    background: rgba(245, 158, 11, 0.1);
    color: var(--accent-orange);
}

.stat-widget-icon.purple {
    background: rgba(139, 92, 246, 0.1);
    color: var(--accent-purple);
}

.stat-widget-info h3 {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 0.25rem;
}

.stat-widget-info p {
    color: var(--text-muted);
    font-size: 0.875rem;
    margin: 0;
}

.assignment-item {
    display: flex;
    align-items: center;
    padding: 1rem;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
    margin-bottom: 0.75rem;
    transition: var(--transition-fast);
    background: white;
}

.assignment-item:hover {
    border-color: var(--primary-blue-light);
    box-shadow: var(--shadow-sm);
}

.assignment-item:last-child {
    margin-bottom: 0;
}

.assignment-icon {
    width: 48px;
    height: 48px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: 1rem;
    font-size: 1.25rem;
}

.assignment-info {
    flex: 1;
}

.assignment-title {
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 0.25rem;
}

.assignment-meta {
    font-size: 0.875rem;
    color: var(--text-muted);
}

.assignment-status {
    padding: 0.375rem 0.75rem;
    border-radius: 50px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.status-pending {
    background: rgba(245, 158, 11, 0.1);
    color: var(--accent-orange);
}

.status-completed {
    background: rgba(16, 185, 129, 0.1);
    color: var(--accent-green);
}

.status-upcoming {
    background: rgba(59, 130, 246, 0.1);
    color: var(--primary-blue-light);
}

.login-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--primary-blue), var(--primary-blue-light));
    padding: 2rem;
}

.login-card {
    background: white;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    width: 100%;
    max-width: 420px;
    overflow: hidden;
}

.login-header {
    background: var(--bg-light);
    padding: 2rem;
    text-align: center;
    border-bottom: 1px solid var(--border-color);
}

.login-logo {
    font-size: 2rem;
    font-weight: 800;
    color: var(--primary-blue);
    margin-bottom: 0.5rem;
}

.login-tagline {
    color: var(--text-muted);
    font-size: 0.875rem;
}

.login-body {
    padding: 2rem;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-label {
    display: block;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 0.5rem;
    font-size: 0.875rem;
}

.form-control-modern {
    width: 100%;
    padding: 0.875rem 1rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 1rem;
    transition: var(--transition-fast);
    background: var(--bg-light);
}

.form-control-modern:focus {
    outline: none;
    border-color: var(--primary-blue-light);
    background: white;
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.btn-login {
    width: 100%;
    padding: 1rem;
    background: linear-gradient(135deg, var(--primary-blue), var(--primary-blue-light));
    border: none;
    color: white;
    font-size: 1rem;
    font-weight: 600;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition-fast);
}

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

.footer {
    background: var(--text-dark);
    color: white;
    padding: 3rem 0 1.5rem;
}

.footer-brand {
    font-size: 1.5rem;
    font-weight: 700;
    color: white;
    margin-bottom: 0.5rem;
}

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

.footer-links a {
    color: var(--text-light);
    text-decoration: none;
    display: block;
    padding: 0.25rem 0;
    transition: var(--transition-fast);
}

.footer-links a:hover {
    color: white;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 1.5rem;
    margin-top: 2rem;
    text-align: center;
    color: var(--text-light);
    font-size: 0.875rem;
}

.progress-ring {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    background: conic-gradient(var(--accent-green) var(--progress, 75%), var(--border-color) 0%);
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}

.progress-ring::before {
    content: '';
    width: 90px;
    height: 90px;
    background: white;
    border-radius: 50%;
    position: absolute;
}

.progress-ring span {
    position: relative;
    z-index: 10;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-dark);
}

.empty-state {
    text-align: center;
    padding: 3rem 2rem;
    color: var(--text-muted);
}

.empty-state i {
    font-size: 3rem;
    margin-bottom: 1rem;
    opacity: 0.5;
}

.empty-state h4 {
    color: var(--text-dark);
    margin-bottom: 0.5rem;
}

@media (max-width: 768px) {
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-tagline {
        font-size: 1.25rem;
    }
    
    .stat-number {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
}