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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: white;
    color: #1f2937;
    transition: background-color 0.3s ease, color 0.3s ease;
}

body.dark-mode {
    background: #1a202c;
    color: #f9fafb;
}

/* Navbar */
.navbar {
    background: #1f2937;
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.nav-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    color: white;
    font-size: 1.5rem;
    font-weight: 700;
    text-decoration: none;
    letter-spacing: -0.02em;
}

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

.nav-links a {
    color: #d1d5db;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s;
    position: relative;
}

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

.nav-links a.active {
    color: white;
}

.nav-links a.active::after {
    content: '';
    position: absolute;
    bottom: -8px;
    left: 0;
    width: 100%;
    height: 2px;
    background: #667eea;
}

.theme-toggle {
    background: transparent;
    border: none;
    color: #d1d5db;
    font-size: 1.25rem;
    cursor: pointer;
    padding: 0.5rem;
    transition: color 0.2s;
}

.theme-toggle:hover {
    color: white;
}

/* Page Transition */
.page-transition {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: #667eea;
    z-index: 9999;
    pointer-events: none;
    opacity: 0;
    transition: opacity 0.3s;
}

/* Main Content */
main {
    min-height: calc(100vh - 70px);
}

/* Page Titles */
h1 {
    font-size: 2.5rem;
    font-weight: 800;
    color: white;
    margin-bottom: 2rem;
}

/* Mobile Styles */
@media (max-width: 768px) {
    .nav-content {
        padding: 0 1rem;
    }
    
    .nav-links {
        gap: 1rem;
        font-size: 0.9rem;
    }
    
    .logo {
        font-size: 1.25rem;
    }
    
    h1 {
        font-size: 2rem;
    }
}