Short answer

Use display:none on the part you want to hide. Right-click it → Inspect to find its class name.

Step by step

1
On your site, right-click the thing → Inspect. Note its class (e.g. class="t-demo").
2
Design & theme → Custom CSS → write .that-class { display: none !important; }
3
To hide it only on phones, put it inside @media (max-width: 760px) { … }.

Copy this code

CSS

/* Hide the floating WhatsApp button on phones */
@media (max-width: 760px) {
  .wa-float, .t-wa { display: none !important; }
}

Paste it in Dashboard → Design & theme → Custom CSS, then press “Save design”.

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