body{display:flex;flex-direction:column;margin:0;padding:0;overflow:hidden;height:100vh}.header{flex:0 0 auto;background-color:#f8f9fa;padding:1rem}.main{flex:1 0 auto;display:flex;flex-direction:column;justify-content:center;align-items:center;text-align:center;padding:1rem;background-color:#fff}.footer{flex:0 0 auto;text-align:center;padding:1rem;background-color:#f8f9fa}