Modifying Blowup theme configuration enables you to customize your theme very easily. To do so, simply fill in the configuration fields or choose a predefined style.

#### Predefined styles

You can choose a predefined style in the Predefined styles drop-down list. Once you have chosen the style, you have to submit the form to apply the modifications.

You may then modify the predefined style according to your taste and needs.

#### Colors

When you have to enter a color value, you should use the hexadecimal format. For example: `#FF0000` will give you red. You may also use the color picker located next to every color field.

If you lack inspiration, try and visit the following pages:

- Color code list (Wikipedia)
- Adobe Kuler
- ColorBlender
- ColorCombos

#### Measurement units

When you have to indicate a size, it must be followed by a measurement unit. For example: `1em`. If you do not include the unit, pixels will be used as default measurement unit.

The following measurement units are available:

- px
- em
- ex
- pt
- %

#### Header images

You can choose a header image among the list to replace the default one.

By choosing Custom... in the image list, you will be able to upload your own image. The image file must be in JPG or PNG format and must be precisely 800px wide.

If you upload a JPG image, a border will be added to the image, which is not the case with PNG images (the transparency of which will also be kept).

#### Configuration import and export

At the bottom of the page, you can display an area called Configuration import/export. This text area contains the configuration you are currently using. You can copy it to share it with others.

To apply (import) a configuration, you simply need to replace the content of the text area with the configuration you want to use. Don't forget to click on Apply code.