.block:not(:last-child) {
    margin-bottom: 1.5rem;
  }

.box {
    margin: 5em auto auto auto;
    text-align: center;
    min-width: 25rem;
    max-width: 65%;
}

h1 {
    font-weight: bold;
    font-size: 200%;
}

h2 {
    font-size: 120%;
 }

h3 {
    font-size: 100%;
}

h4 {
    font-size: 110%;
}

.textspacer {
    margin-bottom: 4rem;
    margin-top: 4rem;
}

#explanation {
    position: relative;
    max-width: 65%;
    align-items: center;
    margin: 0 auto 0 auto;
}