border

• 📘 border - shorthand for border-width, border-style, border-color

• 📘 border-shadow

example

border vs. outline

CSS

.flex {

    width: 300px;
    height: 200px;
    box-sizing: border-box;
    background-color: white;
    
    /* flex */
    display: flex;
    justify-content: center;
    align-items: center;
    
    margin: 30px auto;

    /* ⭐️ border */
    border: 5px solid black;

    /* ⭐️ outline */
    outline: 5px solid orange;
    outline-offset: 0.5rem;

    /* ⭐️ box-shadow */
    /* offset-x | offset-y | blur-radius | spread-radius | color */
    box-shadow: 1px 1px 6px 1px rgba(46, 49, 0, 0.89);
}