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<html><head><meta name="viewport" content="width=device-width, initial-scale=1"><style>/* Variable declarations */ :root { --blue: #1e90ff; --white: #ffffff; }.container { --fontsize: 25px;}/* Styles */ body { background-color: var(--blue);}h2 { border-bottom: 2px solid var(--blue);}.container { color: var(--blue); background-color: var(--white); padding: 15px; font-size: var(--fontsize);}@media screen and (min-width: 450px) { .container { --fontsize: 50px; } :root { --blue: lightblue; }}</style></head><body><h1>Using Variables in Media Queries</h1><div class="container"> <h2>Lorem Ipsum</h2> <p>When the browser's width is 450px or wider, set the --fontsize variable value to 50px and the --blue variable value to lightblue. Resize the browser window to see the effect.</p></div></body></html>