This is an example of a bootstrap grid layout used to display thumbnail details with hover effects, designed using CSS, HTML, and Bootstrap framework 4. The background images of the cards are imported to the code with their URLs. The number of grid items per row is defined as 3, and the gap between each item is set as 1, in CSS. The colors are predefined as primary-color: #333, secondary-color: #fff, and font-color: #fff. For the browser that does not support the grid layout, the background color is set as #00d2ff. The font family for the form is given as 'Roboto', sans-serif. The title of the form is given a style set of color as white, font-size as 30px, text-transform as uppercase to automatically convert the text to uppercase, and font-weight as 700, whereas the subtitle of the form is given the styles of font-size as 18px, and font-weight as 300. In a hover effect, the first card takes a transform effect of transformSkewScale (-45deg, 1), and a transition effect of (all 400ms cubic-bezier(0.175, 0.885, 0.32, 1.275)), whereas the second and third ones take transformSkewScale(45deg, 1), and transformSkewScale(45deg, 0) effects, respectively.