* {
    box-sizing: border-box;
}

body {
    margin: 0;
    color: #252525;
    font-family: Arial, Helvetica, sans-serif;
    background: #f7f7f3;
}

a {
    color: inherit;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
    padding: 18px clamp(16px, 4vw, 56px);
    background: #ffffff;
    border-bottom: 1px solid #dddddd;
}


.brand {
    display: flex;
    align-items: center;
    gap: 12px;
    color: #252525;
    text-decoration: none;
}

.site-footer {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    align-items: center;
    gap: 10px 18px;
    width: 100%;
    margin: 0 auto;
    padding: 20px clamp(16px, 4vw, 40px) 28px;
    text-align: center;
    color: #4c585b;
    font-size: 14px;
    border-top: 1px solid #d8d8d0;
}

.site-footer a {
    color: #005ea8;
    font-weight: 700;
    text-underline-offset: 2px;
}

.brand img {
    width: 172px;
    height: auto;
}

.site-header nav {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.site-header nav a {
    padding: 8px 12px;
    border-radius: 4px;
    text-decoration: none;
    background: #ece9df;
}

.site-header nav a.active {
    color: #ffffff;
    background: #2f6f73;
}

main {
    max-width: 960px;
    margin: 0 auto;
    padding: 24px clamp(16px, 4vw, 40px) 56px;
}

.page-heading h1 {
    margin: 0 0 22px;
    font-size: 32px;
}

.teacher-page {
    display: grid;
    gap: 18px;
}

.teacher-section {
    padding: 18px 0 20px;
    border-top: 1px solid #d8d8d0;
}

.teacher-section:first-of-type {
    border-top: 0;
}

.teacher-section h2 {
    margin: 0 0 12px;
    font-size: 22px;
}

.teacher-section p {
    margin: 0 0 10px;
    line-height: 1.55;
}

.teacher-section a {
    color: #005ea8;
    font-weight: 700;
    text-decoration-thickness: 2px;
    text-underline-offset: 2px;
}

.teacher-section a:hover,
.teacher-section a:focus-visible {
    color: #003f73;
}

.subject-label {
    margin: 0 0 8px;
    color: #687277;
    font-size: 14px;
    font-weight: 700;
    text-transform: uppercase;
}

.download-list {
    display: grid;
    gap: 8px;
    margin: 0;
    padding-left: 22px;
    line-height: 1.45;
}

@media (max-width: 720px) {
    .site-header {
        align-items: flex-start;
        flex-direction: column;
    }

    .site-header nav a {
        padding: 7px 9px;
    }

    .page-heading h1 {
        font-size: 28px;
    }

    .teacher-section h2 {
        font-size: 20px;
    }
}