This is not actually PHP question but HTML related. You can use placeholder="" it does the same thing what you are looking for. You have done almost the same but just remove the value="" form the input field. If you are not calling any value than no need to use it. If you hav
<input type="text" id="full-name" class="long-text" placeholder="Jatin Soni" />
Try above in your code
Or you can do something below
.myclass {
border: 2px solid #003366;
}
<input onfocus="this.className = 'myclass';" onblur="this.className = '';" name="thename" id="thename" type="text" value="Jatin Soni" size="80" maxlength="30">