fix: touch below element together in smartphone (fix #78)

[jajugoguma]

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• [x] It's submitted to right branch according to our branching model
• [x] It's right issue type on title
• [x] When resolving a specific issue, it's referenced in the PR's title (e.g. fix #xxx[,#xxx], where "xxx" is the issue number)
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Description

• Fix problems that touched element below of datePicker together in smartphone

As-Is

To-Be

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