add placeholder to textarea code example

Example 1: textarea placeholder

<!-- Make sure that there is No space and No breaklines between the <textarea></textarea>. Example below: -->
<textarea placeholder="Enter Details..."></textarea>

Example 2: put placeholder text in middle textarea

// Generally if you put a font-size and a height then it will place it in the middle
// - If it still doesnt then use padding-top to be half of padding-bottom.