p {
    text-indent: 50px;
}

The text-indent property specifies how much horizontal space text should be moved before the beginning of the first line of the text content of an element.

Resources:

• http://stackoverflow.com/questions/5856952/indenting-only-the-first-line-of-text-in-a-paragraph
• https://www.w3.org/TR/CSS21/text.html#propdef-text-indent
• https://developer.mozilla.org/en-US/docs/Web/CSS/text-indent