body {
    width: 570px;
    padding: 0 0.5em 0 0;
}

h2 {
    border: 0;
    font-size: 1.5em;
    margin: .83em 0;
    line-height: 1em;
    text-indent: 0;
    padding: .25em;
    /* background: lineargradient(#39F,0); */
    /* border: #135 2px solid; */
    color: white;
    background: linear-gradient(90deg, #26A 40%, #39F, transparent);
  }

h3 {
    color: #26A;
    border-bottom: 2px solid;
    padding: 0 .25em .1em;
    margin: .5em 0 0;
}

h4 {
    color: #26A;
    border-bottom: 1px solid;
    padding: 0 .25em;
    margin: .5em 0 0;
}

p {
    margin: .75em 0;
}

img {
    max-width: 100%;
}

.box {
    border: 2px #39F solid;
    padding: 0 .5em;
    margin: .5em 0 1em;
}

.box>:first-child {
    margin-top: 0.5em;
}

.box>:last-child {
    margin-bottom: 0.5em;
}

.box[data-title]::before {
    display: inline-block;
    content: attr(data-title);
    color: white;
    font-weight: bold;
    background-color: #39F;
    width: 100%;
    margin: 0 -.5em;
    padding: 0.1em .5em;
}

.strongbox {
    color: red;
    font-weight: bold;
    border: 2px solid;
    border-radius: 10px;
    padding: .25em;
    text-align: center;
    margin: .5em;
}