*,::after,::before { boX-sizing: border-boX; } header,main { display: block; } body { margin: 0; font-family: arial,sans-serif,-apple-system,BlinkMacSystemFont,segoe ui,Roboto,helvetica neue,apple ......linear-gradient(180deg,#4f7a9f,#30638e) repeat-x; border-color: #30638e; box-shadow:...linear-gradient(180deg,#476987,#264f71) repeat-x; border-color: #234868; } .btn-primary:focus...