body {font-family: Arial, sans-serif;
    margin: 10px;
    padding: 0;}

.container {padding: 20px;}

.breakpoint {margin: 20px 0;}

@media only screen and (max-width: 600px) {body {background-color: lightblue;}}

@media only screen and (min-width: 601px) and (max-width: 768px) {body {background-color: lightgreen;}}

@media only screen and (min-width: 769px) and (max-width: 1024px) {body {background-color: lightcoral;}}

@media only screen and (min-width: 1025px) {body {background-color: lightgoldenrodyellow;}}