This is an example of a simple contact us form, designed using HTML, CSS, and Bootstrap framework 4. The background color of the form is set as #4DB7FE. The background-size is set as cover for the background image to resize and cover the whole container. The form card is given a border of rgba(68, 68, 65, 0.77), whereas the background color of the card is set to white, with a padding of 20px. The button is created as a primary type button. The styles for the input text fields are set as border-bottom as 1px solid #61615e, background as transparent, and transition as all 0.3s ease 0s. The 'Send Message' button has the styles of display as block, padding as 11px 32px, transition as all 0.3s ease 0s, and margin as 30px 0px. It is also given the styles of background-color as #4285f4, color as #fff, and border as 1px solid #4285f4. Source: https://bbbootstrap.com/snippets/contact-us-responsive-form-91369694