BMI: Improve Input Validation and Error Handling

[Pawankalyan2023]

Summary

PR for Issue no : #23

I have changed the validation part and also included the invalid border so as to indicate the issue clearly while entering data , also changed the styles on the UI part

Checklist

• Linked issue (if any)
• Ran locally without console errors
• Focused scope (kept PR small)
• Updated docs or TODO comments if needed

Screenshots

When both the condition fails :

when one of the condition fails :

if any one of the condition or both the condition fails it will make the border red , and the calculation won't happen when there is a invalid process

[vercel]

@Pawankalyan2023 is attempting to deploy a commit to the hrishikesh-dalal's projects Team on Vercel.

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[venisha-kalola]

add the assigned issue number in the PR request, #(no.) see the original issue number
complete the checklist , add screenshots of other invalid inputs too

[Pawankalyan2023]

add the assigned issue number in the PR request, #(no.) see the original issue number complete the checklist , add screenshots of other invalid inputs too

I have updated the PR , please do check