body { margin: 0; font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue', sans-serif; -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale; } code { font-family: source-code-pro, Menlo, Monaco, Consolas, 'Courier New', monospace; } span { display: inline-block; width: 15%; float: right; } a { color: #000; } a:hover { color: #219837 } img { display: block; margin-left: auto; margin-right: auto; width: 100%; } .iframe-container { overflow: hidden; padding-top: 56.25%; position: relative; } .iframe-container iframe { border: 0; height: 100%; left: 0; position: absolute; top: 0; width: 100%; }