JavaScript · Middle · Question 72 of 75

Why does `el.style.width` return an empty string for a width set in CSS?

✓Correct answer: el.style reflects only inline styles; use getComputedStyle(el).width for the resolved value
2The element hasn't loaded yet
3CSS widths are always auto in JavaScript

Explanation

Computed styles return resolved values in pixels. Reading them forces style/layout calculation, so avoid doing it in tight loops.

Further reading

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