Controlled adaption, optimal user experience, and progressive enhancement techniques - for a specific context

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HTML Attributes
<!-- Cross-platform compatible (Android + iPhone) -->
<a href="tel://1-555-555-5555">+1 (555) 555-5555</a>
Always existed in CSS
<link rel="stylesheet" media="screen" href='desktop.css' />
<link rel="stylesheet" media="print" href='paper.css' />
<link rel="stylesheet" media="handheld" href='mobile.css' />
/* "screen" is Media Type *//* "max-device-width: 480px" is Query *//* If screen is 480px or smaller, apply these CSS Rules */@media only screen and (max-device-width: 480px) {/* CSS RULES */}