Web Development web mobile css

What is Viewport?

Definition

The viewport is the visible area of a web page in the browser window. The HTML meta viewport tag (<meta name='viewport' content='width=device-width, initial-scale=1'>) controls how the page scales on mobile devices.

Why It Matters

Without a proper viewport meta tag, mobile browsers render pages at desktop width and then shrink them, making text unreadable. The viewport meta tag is required for responsive design to work. CSS viewport units (vw, vh) are relative to viewport size.

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