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CSS Quiz Practice
Active Recall Drill Session
← Exit Session
Question 1 of 1
medium
CSS
Why does `width: var(--base-width) + 10px;` not work as arithmetic, requiring calc() instead?
A
var() is not valid inside the width property
B
Custom properties substitute their value as literal CSS token text — arithmetic requires wrapping the expression in calc()
C
CSS does not support addition under any circumstances
D
This syntax works correctly without calc()
Check Answer