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

body {

    font-family: Arial, sans-serif;

    background-color: #0f172a;

    color: white;
}

header {

    background-color: #111827;

    padding: 20px 50px;

    display: flex;

    justify-content: space-between;

    align-items: center;

    border-bottom: 1px solid #374151;
}

header h1 {

    font-size: 28px;
}

nav {

    display: flex;

    gap: 25px;
}

nav a {

    text-decoration: none;

    color: white;

    font-size: 16px;

    transition: 0.3s;
}

nav a:hover {

    color: #38bdf8;
}

button {

    cursor: pointer;

    border: none;
}

@media (max-width: 768px) {

    header {

        flex-direction: column;

        gap: 20px;
    }

    nav {

        flex-wrap: wrap;

        justify-content: center;
    }
}