Check out example codes for "style input field". It will help you in understanding the concepts better.

Code Example 1

/* Style input based on type */
input[type=text] 
{

}

Code Example 2

#userInfoForm {
    width: 80%;
    padding: 5px 5px;
    margin: 0 auto;
    background: #FF6700;
    border-radius: 25px; 
}

#userInfoForm input {
    width: 100%;
    padding: 12px 20px;
    margin: 8px 0;
    box-sizing: border-box;
    border-radius: 25px;
}

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