What we'll be creating:
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Figma tutorial
1) Add a fixed size square to the 'paper' element
I'm assuming your containing element has auto-layout already applied.
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2) Apply 'Position: Absolute' to the square
The square will no longer take up space in the layout. It can be moved freely.
Move the square to the corner.
Important: Change the square's color so that it equals that of the background (the element behind the 'paper' element).
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3) Add another, equal size square
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4) Edit the square and turn it into a triangle
Simply drag the corner vector point. Doesn't have to be exact.
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5) Position the triangle on top of the first square
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6) Edit and round corners as needed
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Done!
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Webflow tutorial
What we'll be creating:
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1) Give the containing 'paper' element a Position of Relative
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2) Add a div (it'll be the corner fold)
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3) Make sure it has no width or height + Give it some color and a thick border
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4) Change its position to Absolute
Move it to the top left corner.
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5) Change the border color of the top and left borders so they are the same color as the background
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Why does this work?
Div borders meet each other at an angle..
When the div has no height or width, the borders become triangles.
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