html, 
body {
    height: 100%;
}

body {
    margin: 0;
}

.header {
    height: 100px;
    box-shadow: 3px 3px 5px 6px #ccc;
    display: flex;
    align-items: center;
    justify-content: center;
}
.header-company {
    font-size: 30px;
    font-weight: 600;
}
.content {
    font-size: 18px;
    margin-top: 30px;
    height: calc(100% - 130px);
}
.content.home {
    display: flex;
    justify-content: center;
    align-items: center;
}
.menu {
    margin-left: 30px;
}
.menu a {
    font-size: 18px;
    margin-right: 10px;
    color:black;
}