Is there a way to animate the border lines of button menus in Webflow, wherein the line appears from left to right as if it's being drawn, instead of just changing the width?

Yes, there is a way to achieve the effect of animating border lines of button menus in Webflow to appear as if they are being drawn. Instead of simply changing the width, you can use a combination of CSS transitions and pseudo-elements to create the desired animation.

Here is a step-by-step guide to help you implement this effect:

1. Add a button menu element to your Webflow project. You can use the built-in navbar component or create a custom button menu using div elements.

2. Select the button menu element and navigate to the Styles panel. Scroll down to the Border section and set the border width to the desired starting width.

3. Next, click on the "plus" icon (+) next to the border width property. This will create a new hover state for the button menu.

4. With the hover state selected, increase the border width to the desired ending width. This will be the fully drawn line width.

5. Now, switch to the Settings tab in the right panel and set the transition duration for the border width property. For example, you can set it to 0.5s to create a smooth animation effect.

6. To achieve the effect of the line appearing from left to right, we will use pseudo-elements. Select the button menu element and click on the "plus" icon (+) next to the "Before" or "After" property in the Styles panel.

7. Position the pseudo-element on the left side of the button menu element by setting its position to absolute and adjusting the left value. You can also set the pseudo-element's width to 0 and give it a height equal to the button menu's height.

8. Apply the desired animation effect to the pseudo-element by adding a transition on its width property. Set the transition duration to match the duration you set for the border width transition in step 5.

9. Finally, add a hover interaction to the button menu element. In the Interaction panel, choose the Hover trigger and select the pseudo-element. Set the width value of the pseudo-element to match the ending width of the border lines. This will trigger the animation when the button menu is hovered over.

By following these steps, you should be able to create an animated border line effect where the lines appear as if they are being drawn from left to right. Remember to customize the styles, timing, and positioning to match your design preferences.

Note that this technique requires some advanced knowledge of CSS and Webflow interactions, so it may take some experimentation and tweaking to achieve the desired result.