By default, any styles you’ve applied such as a strokes, border radius or shadow sizes will stay the same when you resize a layer. If you want to scale them proportionately with your layer size, head to Layer > Transform > Scale, right-click and choose Transform > Scale, or press K.
In the Layout · Scale section of the Inspector, you can choose whether your layer will resize from its center, sides or corners. Your layer will automatically scale as you change its properties.
As you scale, Smart Guides show measurements against nearby layers and help you snap to them. Hold ⌃ to temporarily turn them off.
When you’re done, click anywhere else on the Canvas. Alternatively, click Done or press ⏎.
