Issue 96 Make the word visibility clear

[abansal15]

Overview

1. This PR fixes or fixes part of [BUG]: The alt of image dark mode which is switch is not visible clearly when alt is shown instead of image in slow net #96 .
2. This PR does the following: [ Make the word visibility clear ]

Essential Checklist

• The PR title starts with "Fix [BUG]: The alt of image dark mode which is switch is not visible clearly when alt is shown instead of image in slow net #96 : ", followed by a short, clear summary of the changes. (If this PR fixes part of an issue, prefix the title with "Fix part of #bugnum: ...".)
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• The PR is made from a branch that's not called "main/master".

Proof that changes are correct

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