🧊 How to Apply a Glass Effect to a Rectangle in Adobe Illustrator

✅ Step 1: Draw the Base Shape

1. Open Adobe Illustrator and create a new document.

2. Select the Rectangle Tool (M).

3. Click and drag on the artboard to draw your rectangle.

✅ Step 2: Add a Gradient Fill

1. With the rectangle selected, go to the Gradient panel (Window > Gradient).

2. Apply a white-to-transparent linear gradient:

   • Use white (or light gray) on one end.

   • Use 100% opacity for white, and 0% opacity on the other end.

3. Adjust the angle and gradient position to match the light source.

✅ Step 3: Lower the Opacity

1. Open the Transparency panel (Window > Transparency).

2. Reduce the opacity to 20–30%, depending on how "frosted" you want the effect.

✅ Step 4: Add a Blur Background (Optional)

If you want to simulate content behind the glass:

1. Create some shapes/text behind the glass rectangle.

2. Select them.

3. Go to Effect > Blur > Gaussian Blur.

4. Apply a blur (e.g., 5–15 px) to simulate background blur.

This creates the illusion that the glass is blurring what's behind it.

✅ Step 5: Add Inner Shine (Highlight)

1. Copy the original rectangle (Ctrl+C) and paste in place (Ctrl+F).

2. Change the fill to white and reduce the opacity to around 5–10%.

3. Use Effect > Blur > Gaussian Blur to slightly blur it.

4. Resize it slightly smaller or move it upward for a subtle shine effect.

✅ Step 6: Add a Stroke (Optional)

1. Add a white or light gray stroke.

2. Reduce the stroke's opacity to 10–20%.

3. Set it to Inside (via Appearance panel > Stroke > Align Stroke to Inside) for a smooth border.

✅ Step 7: Group and Save

1. Select all glass elements and group them (Ctrl+G).

2. Done! Now you have a frosted glass-style effect.