Format menu >> background selection.
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Make your Word document a more beautiful background
As you know, in the default settings, the background of the Word document is drab white. If you like to make it more beautiful, you can try to change the background in the following ways.
One, add color background
Click on the menu "format" → "background", in the color panel directly clicks the color you want. If the color above is not what you want, you can also choose a different color by clicking more Colors.
Add a gradient, texture, or pattern
Also, click Fill Effects to add gradients, textures, or patterns, and adjust the color of the texture or pattern to your liking.
If you want to remove the settings, perform the format → background, and then click No Fill. If you want to preview or print a background effect, perform the tools → options → print tab, select the background color and image check box.
Third, add a picture watermark
As above, click Watermark to open the Watermark dialog box to add a picture watermark or text watermark to your document. For example, add your photo or name, it will create the effect of the copyright page.
If you want to remove the watermark, you can select No watermark from the Watermark dialog box. In addition, watermarks are designed for printed documents and are not visible in Word's normal view, Web layout view, outline view, and reading layout. When you add a watermark to the header footer view, you can adjust the color or size of the watermark picture and WordArt.
Iv. changing the style of the document
If you're tired of Word's default white background black Word document style, you can choose another document style from the tools → options → general tab, such as the "white text on blue" check box, to change the style, may make your eyes and mood for one bright.