How do you target all even or odd elements using a pseudo-selector in CSS?
Interviewer Expectations for this Question
01
Core Competency
Assesses fundamental understanding of HTML & CSS conventions, runtime behavior, and memory/performance considerations.
02
Evaluation Criteria
Hiring managers look for precision, avoidance of ambiguous jargon, and ability to explain trade-offs under real production conditions.
Comprehensive Model Answer
Verified Solution
You can target alternating rows or elements using the :nth-child() structural pseudo-class with the keywords even or odd:
/* Zebra striping table rows */
tbody tr:nth-child(odd) {
background-color: #ffffff;
}
tbody tr:nth-child(even) {
background-color: #f8fafc;
}
### Algebraic Notation (An + B):
The even keyword is functionally equivalent to :nth-child(2n), matching elements at indices 2, 4, 6, 8...
The odd keyword is equivalent to :nth-child(2n+1), matching elements at indices 1, 3, 5, 7...
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