We know that sometimes in the process of writing code, we will find that the z-index I wrote is invalid, so this time I will bring you why z-index will fail and why z-index is used. NotesWhat are the following? Let’s take a look at the actual cases.
1. The parent tag position attribute is relative;
2. The question tag has no position attribute (excluding static );
3. The question label contains float(float) attribute.
4. The z-index value of the ancestor tag of the question tag is relatively small.
If this is the case, only absolute and fixed positions are left.
I believe you have mastered the methods after reading these cases. For more exciting information, please pay attention to other related articles on the php Chinese website!
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How to operate the child page of iframe to shield the page pop-up layer effect of the parent pagehtml standard writing method and What are the differences in the code generated by dreamweaverHow to achieve mixed graphics and text in htmlThe above is the detailed content of Why does z-index fail?. For more information, please follow other related articles on the PHP Chinese website!