css - My canvas gets 2 borders instead of one -

I have several canvases on my page. I should all leave one and get a thin border, which has a thick border I want to insert all the border information into the element inside the HTML head. Here's my attempt:

  & lt; Style & gt; / * In the canvas with thick border, the ID is 'C' * / # C. Border: 8px solid # 8525AA; } Canvas {boundary: 2px solid # 5408FA; } & Lt; / Style & gt;  

This is a fraction of my HTML body:

  & lt; Canvas ID = "Filler" width = "10" height = "70" & gt; & Lt; / Canvas & gt; & Lt; Canvas id = "c" width = "400" height = "200" & gt; & Lt; / Canvas & gt; & Lt ;! - Follow more canvas here - & gt;  

Problem: With this code, the canvas two boundaries, with the id 'c', become one thick and thin! Is it intentional behavior? If so, how can I achieve my goal?

Try changing your CSS like this:

  & Lt; Style & gt; / * Id 'c' * / canvas in broadband canvas {range is: 2px solid # 5408FA; } # C {range: 8px solid # 8525AA; } & Lt; / Style & gt;