:root {
    --primary: #1f4f82;
    --secondary: #f5f7fa;
    --text: #222;
    --border: #d8d8d8;
}

*,
*::before,
*::after {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: Arial, Helvetica, sans-serif;
    line-height: 1.7;
    background: var(--secondary);
    color: var(--text);
}

header,
main,
footer {
    max-width: 1100px;
    margin: auto;
    padding: 1.5rem;
}

header {
    text-align: center;
    border-bottom: 4px solid var(--primary);
}

h1 {
    margin-bottom: .25rem;
    font-size: 2.6rem;
    color: var(--primary);
}

h2 {
    color: var(--primary);
    border-bottom: 2px solid var(--primary);
    padding-bottom: .4rem;
    margin-top: 2rem;
}

h3 {
    margin-bottom: .4rem;
}

h4 {
    margin-top: 1rem;
}

address {
    font-style: normal;
}

nav ul {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 1rem;
    list-style: none;
    padding: 0;
    margin-top: 1.5rem;
}

nav a {
    text-decoration: none;
    color: var(--primary);
    font-weight: bold;
}

nav a:hover,
nav a:focus {
    text-decoration: underline;
}

main {
    display: grid;
    gap: 1.5rem;
}

section,
aside {
    background: white;
    padding: 1.5rem;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,.08);
}

article {
    margin-bottom: 1.5rem;
}

ul {
    padding-left: 1.5rem;
}

dl {
    display: grid;
    grid-template-columns: max-content auto;
    gap: .5rem 1rem;
}

dt {
    font-weight: bold;
}

a {
    color: var(--primary);
}

a:focus {
    outline: 3px solid #ffbf47;
    outline-offset: 2px;
}

footer {
    text-align: center;
    margin-top: 2rem;
    border-top: 2px solid var(--primary);
    padding-top: 1rem;
}

@media (max-width: 768px) {

    header,
    main,
    footer {
        padding: 1rem;
    }

    h1 {
        font-size: 2rem;
    }

    nav ul {
        flex-direction: column;
        align-items: center;
    }

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