:root {
    --primary: #0a2540;
    --accent: #00aaff;
    --light: #f4f7fb;
}

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

body {
    font-family: Arial, sans-serif;
    background: var(--light);
}

.container {
    width:90%;
    max-width:1100px;
    margin:auto;
}

header {
    background: var(--primary);
    color:white;
    padding:15px 0;
    position:sticky;
    top:0;
}

.header-inner {
    display:flex;
    justify-content:space-between;
    align-items:center;
}

nav a {
    color:white;
    margin-left:20px;
    text-decoration:none;
}

nav a.active {
    border-bottom:2px solid var(--accent);
}

.burger {
    display:none;
    font-size:26px;
    cursor:pointer;
}

.hero {
    background:#1c3d5a;
    color:white;
    text-align:center;
    padding:80px 20px;
}

.btn {
    background:var(--accent);
    padding:12px 25px;
    color:white;
    text-decoration:none;
}

.section {
    padding:50px 0;
}

.section.alt {
    background:white;
}

.grid {
    display:grid;
    grid-template-columns:repeat(4,1fr);
    gap:20px;
}

.card {
    background:white;
    padding:20px;
    border-radius:8px;
}

.list {
    list-style:none;
}

footer {
    background:var(--primary);
    color:white;
    text-align:center;
    padding:20px;
}

footer a {
    color:var(--accent);
}

@media(max-width:768px) {

    nav {
        position:absolute;
        right:0;
        top:60px;
        background:var(--primary);
        flex-direction:column;
        display:none;
        padding:20px;
    }

    nav.active {
        display:flex;
    }

    .burger {
        display:block;
        color:white;
    }

    .grid {
        grid-template-columns:1fr;
    }
}