* {box-sizing: border-box;}html, body {margin: auto;padding: 10px;max-width: 80ch;font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;color: black;background-color: rgb(233, 234, 247);}a {text-decoration: none;color: rgb(43, 109, 230);}header, .link {background-color: rgb(43, 109, 230);color: white;padding: 10px;object-position: center;border-radius: 5px;text-align: center;}main {background-color: rgb(237, 244, 252);padding: 20px;padding-left: 40px;padding-right: 40px;margin-top: 20px;margin-bottom: 10px;object-position: center;border-radius: 5px;}.desc {font-size: 12px;padding: 3px;}.postlist-link {padding: 10px;font-size: 20px;color: darkslateblue;}.button {background-color: rgb(43, 109, 230);color: white;padding: 10px;border-radius: 5px;}.video {position: relative;padding-bottom: 56.25%;height: 0;}.video iframe {position: absolute;top: 0;left: 0;width: 100%;height: 100%;border-radius: 5px;background-color: rgb(43, 109, 230);}footer, footer a:link {font-size: 12px;text-align: center;color: black;}h3 {font-size: 32px;}