html, body { height: 100%; width: 100%; margin: 0; }

body {  display: table; }

header, footer { background-color: #333; color: #fff; text-align: center; padding: 1rem; }

header { display: table-header-group; }

main { display: table-row; width: 100%; background: #f4f4f4; }

footer { display: table-footer-group; }

section { background: white; margin: 1rem auto; padding: 1rem; max-width: 1024px; width: calc(100%-2rem); }

section details { display: inline-block; margin: 1rem; vertical-align: top; }