This is an example of a collapsible menu layout, designed using HTML, CSS, JavaScript, and Bootstrap framework 4. JavaScript has been used to implement the expanding function of the menu. The fonts are imported to the code with the URL. The concept of Lists has been used with UL and LI components. UL element has been used with the child elements of LI to display the menu items in an orderly manner. The body of the form is given the styles of color as #444246, background as linear-gradient(to bottom, #dd879f 0%,#4e337e 100%), font-family as 'Open Sans', sans-serif, and padding as 10% 0 0 40%. The text is given a text-transform style as uppercase to automatically convert the text to uppercase, and also the cursor style as pointer to get the hand cursor effect in a hover event. The menu list items are given the styles of display as block, min-height as 48px, font-weight as bold, font-size as 0.76em, position as relative, and border-bottom as 1px solid rgba(255,255,255,0.1), which takes the background color of #3ed8b5, in a hover event. Source: https://codepen.io/chrisota/pen/hkAFm