Head over to the Custom Branding page in Org Settings.
You can customize your logo and brand color using the settings below. The preview box to the right will reflect your changes in real time so you can see how it looks before you save. Once you're happy with the settings, save your changes and it will be applied to all users. Note: there is no auto-save so make sure you save your changes before leaving the page.
You can change the background color above the left navigation bar behind your company logo or name. You can choose from a pre-selected color palette or by entering a hex code.
You can also add a custom color to the navigation bar highlight in the same way as the logo background color:
You can also upload your company logo or use plain text for your company name.
If you are uploading a logo, here's what to keep in mind:
Recommended: logo images should be 48x410 pixels and up for best results (images will be scaled to fit)
Supported: PNG, JPEG, GIF, SVG
Recommended: PNG or SVG for best results
Recommended: transparent backgrounds will give best results (only available in PNG or SVG image files)