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

body {
    font-family: '-apple-system', BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    min-height: 100vh;
    background: linear-gradient(135deg, #0f2027, #203a43, #2c5364);
    color: #ffffff;
    overflow-x: hidden;
}

.main-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 70px;
    display: flex;
    justify-content: center;
    align-items: center;
    background: rgba(15, 32, 39, 0.8);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    z-index: 1000;
}

.nav-container {
    display: flex;
    gap: 1.5rem;
}

.nav-link {
    color: #ffffff;
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    padding: 0.6rem 1.2rem;
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: all 0.3s ease;
    letter-spacing: 1px;
}

.nav-link:hover, .nav-link.active {
    background: #00d2ff;
    color: #0f2027;
    border-color: #00d2ff;
    box-shadow: 0 0 15px rgba(0, 210, 255, 0.4);
    transform: translateY(-2px);
}

@media (max-width: 768px) {
    .nav-container { gap: 0.4rem; }
    .nav-link { font-size: 0.75rem; padding: 0.4rem 0.7rem; }
}