body {
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
}

header {
    background: #eeeeee;
    border-bottom: 1px solid #dddddd;
}

.fixed-header header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    overflow: hidden;
    flex-shrink: 0;
    z-index: 1;
}

.fixed-header main {
    padding-top: var(--header-height);
}

.fixed-footer main {
    padding-bottom: var(--footer-height);
}

footer {
    margin-top: auto;
    background: #eeeeff;
    border-top: 1px solid #dddddd;
}

.fixed-footer footer {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    height: var(--footer-height);
    overflow: hidden;
    flex-shrink: 0;
}

header menu {
    display: flex;
    align-items: center;
}