body { font: 17px/1.55 -apple-system, BlinkMacSystemFont, "Helvetica Neue", sans-serif; max-width: 640px; margin: 0 auto; padding: 32px 16px; color: #1d1d1f; background: #c0c0c0; }
main { background: #fff; padding: 24px; border: 3px solid; border-color: #fff #808080 #808080 #fff; }
h1 { margin-top: 0; font-size: 28px; }
a { color: #0000c0; }