When you go to your organization settings, any user with Organization Administrator permissions can customize template settings from the Proposal phase on the menu.
To start, click on the gear icon on the top right of the platform. Then choose Proposal Phase on the left menu. 
From here, you can customized all unlocked templates. You'll know it's customizable if there is no lock icon on the template preview's top left corner. For this example, we chose to customize Sighten EverBright Proposal (copy). To proceed, click on the preview to open the template and then click Settings on the left menu.
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This is where the color scheme for a proposal template can be edited. You can update up to 8 color selections to match your companies exact branding, including the colors used to show different quotes you include for comparison and for charts.
Background: this sets the colors used for the top bar, page background, and side bar background.
Text: this sets the colors used to show the quotes included in the proposal. The primary color is used for the first quote included in the proposal. If you include a second or third quote, the secondary and tertiary colors will be used.
Charts: this sets the colors used in proposal charts, like the usage offset charts and the display system production vs consumption.
You can also confirm or switch what logo would be used. By default, the logo included in your company profile is used.
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Related articles
Check out these related articles on using SightenEverBright's MyProposal:
What does MyProposal look like and what is the homeowner experience?
How do I get started with my company's new customized MyProposal?
Existing proposal: How do I change my company's proposal settings & content?