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

:root {
    --primary: #667eea;
    --primary-dark: #5a67d8;
    --secondary: #764ba2;
    --success: #48bb78;
    --danger: #f56565;
    --warning: #ed8936;
    --info: #4299e1;
    --light: #f7fafc;
    --dark: #2d3748;
    --gray: #718096;
    --gray-light: #e2e8f0;
    --shadow: 0 2px 10px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 30px rgba(0,0,0,0.15);
    --radius: 8px;
    --radius-lg: 12px;
    --transition: all 0.3s ease;
}

body {
    font-family: 'Poppins', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--dark);
    background-color: var(--light);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
}

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

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius);
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    outline: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: white;
}

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

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

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

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

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

/* Navigation */
.navbar {
    background: white;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
    padding: 1rem 0;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--dark);
}

.logo .highlight {
    color: var(--primary);
}

.nav-menu {
    display: flex;
    gap: 2rem;
    align-items: center;
}

.nav-link {
    color: var(--gray);
    font-weight: 500;
    padding: 0.5rem 0;
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary);
}

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

.admin-btn {
    background: var(--primary);
    color: white !important;
    padding: 0.5rem 1rem;
    border-radius: var(--radius);
}

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

.menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--dark);
    cursor: pointer;
}

/* Hero Section */
.hero {
    padding: 4rem 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}

.hero-content h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.hero-content p {
    font-size: 1.1rem;
    opacity: 0.9;
    margin-bottom: 2rem;
}

.hero-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
    margin-top: 2rem;
}

.stat {
    display: flex;
    align-items: center;
    gap: 1rem;
    background: rgba(255,255,255,0.1);
    padding: 1rem;
    border-radius: var(--radius);
    backdrop-filter: blur(10px);
}

.stat i {
    font-size: 2rem;
}

.stat h3 {
    font-size: 1.8rem;
    margin-bottom: 0.25rem;
}

.stat p {
    font-size: 0.9rem;
    opacity: 0.8;
}

.hero-image img {
    width: 100%;
    height: auto;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
}

/* Features Section */
.features {
    padding: 5rem 0;
    background: white;
}

.section-title {
    text-align: center;
    font-size: 2rem;
    margin-bottom: 3rem;
    color: var(--dark);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.feature-card {
    padding: 2rem;
    border-radius: var(--radius);
    background: var(--light);
    transition: var(--transition);
    text-align: center;
}

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

.feature-icon {
    width: 70px;
    height: 70px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
    font-size: 1.5rem;
    color: white;
}

.feature-card h3 {
    margin-bottom: 1rem;
    color: var(--dark);
}

/* Files Section */
.files-section {
    padding: 5rem 0;
}

.files-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-bottom: 3rem;
}

.file-card {
    background: white;
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

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

.file-icon {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    padding: 2rem;
    text-align: center;
    color: white;
    font-size: 2.5rem;
}

.file-info {
    padding: 1.5rem;
}

.file-title {
    font-size: 1.2rem;
    margin-bottom: 0.75rem;
    color: var(--dark);
}

.file-desc {
    color: var(--gray);
    font-size: 0.9rem;
    margin-bottom: 1rem;
    line-height: 1.5;
}

.file-meta {
    display: flex;
    gap: 1rem;
    font-size: 0.8rem;
    color: var(--gray);
    margin-bottom: 1rem;
}

.file-meta span {
    display: flex;
    align-items: center;
    gap: 0.25rem;
}

.file-actions {
    display: flex;
    gap: 0.5rem;
}

.btn-view {
    background: var(--gray-light);
    color: var(--dark);
}

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

/* Pagination */
.pagination {
    display: flex;
    justify-content: center;
    gap: 0.5rem;
    margin-top: 2rem;
}

.page-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: var(--radius);
    background: white;
    color: var(--dark);
    font-weight: 500;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.page-link:hover,
.page-link.active {
    background: var(--primary);
    color: white;
}

/* Footer */
.footer {
    background: var(--dark);
    color: white;
    padding: 4rem 0 2rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 3rem;
    margin-bottom: 3rem;
}

.footer-section h3 {
    font-size: 1.2rem;
    margin-bottom: 1.5rem;
    color: white;
}

.footer-section p {
    color: var(--gray-light);
    margin-bottom: 1.5rem;
}

.footer-section a {
    display: block;
    color: var(--gray-light);
    margin-bottom: 0.5rem;
}

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

.social-links {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
}

.social-links a {
    width: 40px;
    height: 40px;
    background: rgba(255,255,255,0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

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

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid rgba(255,255,255,0.1);
    color: var(--gray-light);
    font-size: 0.9rem;
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 4rem 2rem;
    color: var(--gray);
}

.empty-state i {
    font-size: 4rem;
    color: var(--gray-light);
    margin-bottom: 1rem;
}

.empty-state h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
    color: var(--dark);
}

/* Form Elements */
.form-control {
    width: 100%;
    padding: 0.875rem 1rem;
    border: 1px solid var(--gray-light);
    border-radius: var(--radius);
    font-size: 1rem;
    transition: var(--transition);
    background: white;
}

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

select.form-control {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' fill='%23718096' viewBox='0 0 16 16'%3E%3Cpath d='M7.247 11.14 2.451 5.658C1.885 5.013 2.345 4 3.204 4h9.592a1 1 0 0 1 .753 1.659l-4.796 5.48a1 1 0 0 1-1.506 0z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 1rem center;
    background-size: 16px 12px;
    padding-right: 2.5rem;
}

textarea.form-control {
    min-height: 100px;
    resize: vertical;
}

/* Alerts */
.alert {
    padding: 1rem 1.5rem;
    border-radius: var(--radius);
    margin-bottom: 1.5rem;
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
    font-size: 0.9rem;
}

.alert i {
    font-size: 1.2rem;
    flex-shrink: 0;
}

.alert-success {
    background: #f0fff4;
    color: #276749;
    border: 1px solid #c6f6d5;
}

.alert-error {
    background: #fff5f5;
    color: #c53030;
    border: 1px solid #fed7d7;
}

/* Responsive Design */
@media (max-width: 992px) {
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-stats {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (max-width: 768px) {
    .nav-menu {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 1rem;
        box-shadow: var(--shadow);
    }
    
    .nav-menu.active {
        display: flex;
    }
    
    .menu-toggle {
        display: block;
    }
    
    .hero-stats {
        grid-template-columns: 1fr;
    }
    
    .files-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .social-links {
        justify-content: center;
    }
}

@media (max-width: 576px) {
    .hero-content h1 {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 1.5rem;
    }
    
    .container {
        padding: 0 1rem;
    }
}