You could upload an image logo for the header, loading, and footer in SEA Theme > Theme Options > General Settings.

If you want to set a plain text logo, please turn on the “Enable Plain Text Logo”. The “Logo Text” input will be shown.
Image Logo
If you want to set a image logo, please turn off the “Enable Plain Text Logo”. The logo image uploader will be shown. You need to upload(or select from WordPress media library) a logo image to “Default Image Logo”.
The custom logo supports JPG, PNG, GIF, and SVG format. The SVG Support plugin should be installed if you use the SVG logo.
If you want to set plain text logo, please activate “Enable Plain Text Logo” to set.
If you want to show a different color logo on particular pages, please upload the logo from “Alternative Image Logo”.

Alternative Logo
If there are some special pages with different background colors, the logo maybe not clear on this BG color (e.g. dark logo on the dark fullscreen slider). You could a different color logo on particular pages(e.g. show a Light logo for a Dark page).

Please upload the logo from “Alternative Image Logo”. If you use the Plain Text as a logo, you could define the Alternative color in “Theme Option > Colors”.
Mobile Logo
You could upload the different image files(Default Image Logo for Mobile, Alternative Logo for Mobile) for the mobile. The Default and Alternative logo(desktop) will NOT be shown on the mobile.

Logo Size
The custom logo is limited to 40px(desktop)/30px(mobile) height by default, and you could set the height for Desktop and Mobile layout. You could enter the number to define the logo height for Desktop and Mobile. It will ignore the default 40/30 height limit.

Page Loader Logo
If you want to show the Logo on Page Loader(Theme Options > General Settings: Page Loader), please upload(or select from WordPress media library) a logo image. The default height is 60px(desktop)/60px(mobile).
Footer Logo
You could set a Logo for the footer bar. The default height is 30px(desktop)/20px(mobile). You need to select “Logo” from the “Theme Options > Footer > Footer Elements”, the logo will be shown on the footer bar.