/* Reset and base styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
header {
    background-color: #fff;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: #007bff;
    text-decoration: none;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-links a {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s ease;
}

.nav-links a:hover {
    color: #007bff;
}

/* Main content */
main {
    min-height: calc(100vh - 140px);
    padding: 2rem 0;
}

.page-title {
    text-align: center;
    margin-bottom: 2rem;
    color: #333;
}

/* Cards */
.card {
    background: #fff;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    padding: 2rem;
    margin-bottom: 2rem;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    background-color: #007bff;
    color: #fff;
    text-decoration: none;
    border-radius: 5px;
    border: none;
    cursor: pointer;
    font-size: 1rem;
    transition: background-color 0.3s ease;
}

.btn:hover {
    background-color: #0056b3;
}

.btn-secondary {
    background-color: #6c757d;
}

.btn-secondary:hover {
    background-color: #545b62;
}

/* Footer */
footer {
    background-color: #333;
    color: #fff;
    text-align: center;
    padding: 1rem 0;
    margin-top: auto;
}

/* Responsive design */
@media (max-width: 768px) {
    .container {
        padding: 0 15px;
    }
    
    nav {
        flex-direction: column;
        gap: 1rem;
    }
    
    .nav-links {
        gap: 1rem;
    }
    
    .card {
        padding: 1.5rem;
    }
    
    .page-title {
        font-size: 1.5rem;
    }
}

/* Utility classes */
.text-center {
    text-align: center;
}

.mb-2 {
    margin-bottom: 1rem;
}

.mb-3 {
    margin-bottom: 1.5rem;
}

.mt-2 {
    margin-top: 1rem;
}

.mt-3 {
    margin-top: 1.5rem;
}