How to lay out non-standard tabs?

Question

css

You need to lay out 3 non-standard tabs. One border-radius and scale for pseudo-classes is indispensable here. The hardest part is the smooth bottom edge. I would like to do without svg of course. What are some ideas? Thank you!
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Answer 1

Make the tabs themselves via wide ("overlapping") images (possibly using css clip-path; although it seems possible to do without this) and use a negative z-index for all inactive tabs positioned below the active one (on the Y-axis, i.e. active - "raise" through JS).