How do I get this code block to be full width?

Site URL: https://www.guygroove.net/widget

Hello!

I essentially want this code box to be full width. In my mind the widget inside the code block should expand to a grid like view afterwards. 

Sorry I know this type of question has been asked time and time again but I'm still finding it difficult. 

The password to the site is: test

Thank you in advance.

Add to Design > Custom CSS

/* Code block fullwidth */
div#block-yui_3_17_2_1_1612245654784_5921 {
    width: 100%;
}