main {
    width: 100%;
    height: 100%;
    background-color: #fff;
    margin-top: 70px;
    margin-bottom: 20px;
    justify-content: center;
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    z-index: 100;
}

main h1 {
    width: 100%;
    flex-basis: 100%;
    margin-top: 10px;
    font-size: 4rem;
    text-align: center;
}

.index-portfolio-box {
    /*width: 500px;
    height: 100px;*/
    display: flex;
    justify-content: center;
    align-items: center;
    position: relative;
    margin: 20px;
    border: 2px solid blue;
}


section {
    margin: 0 auto;
    padding: 0 20px;
    max-width: 800px;
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
}

.subnav {
    padding: 0;
}

.subnav ul {
    width: 100%;
    list-style: none;
    display: flex;
    justify-content: space-evenly;
    margin-bottom: 20px;
}

.subnav a {
    font-family: 'Oswald', sans-serif;
    font-size: 2.5rem;
    line-height: 2.7rem;
    color: #000;
    display: block;
    height: 100%;
    transition: all ease-in-out 200ms;
    text-decoration: underline;
    text-align: center;
}

.subnav a:hover {
    color: red;
}

.anchor {
    display:block;
    padding-top:100px;
    margin-top:-100px;
 }

h2, h2 a {
    width: 100%;
    flex-basis: 100%;
    margin-top: 10px;
    font-size: 3rem;
    text-align: center;
    text-transform: none;
}

h2 {
    margin-bottom: 20px;
}

section h4 {
    font-family: 'Oswald', sans-serif;
    width: 100%;
    flex-basis: 100%;
    font-size: 3rem;
    text-align: center;
    text-transform: none;
}

h2 a {
    text-decoration: underline;
}

h3 {
    font-size: 3rem;
}

main p, section p {
    width: 100%;
    flex-basis: 100%;
    font-size: 2rem;
    line-height: 2.4rem;
    margin-bottom: 20px;
}

main p {
    width: 600px;
    flex-basis:auto;
}

.centered {
    text-align: center;
}

section img {
    max-height: calc(100vh - 140px);
    margin-bottom: 20px;
}

.collapsed {
    width: 100%;
    height: 0;
}

iframe {
    margin: 20px;
}

.backtotop {
    text-align: center;
    flex-basis: 100%;
    font-size: 2rem;
    text-decoration: underline;
    transition: all ease-in-out 200ms;
    margin-bottom: 20px;
}

.backtotop:hover {
    color: red;
}

.centerlink {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    text-align: center;
}

.centerlink p {
    text-decoration: underline;
    color: blue;
}

.centerlink p:hover {
    color: red;
}

@media only screen and (min-width: 768px) {

    main {
        margin-top: 110px;
    }

}