1) Click here to open your Weebly Editor

2) Click into “design” then into “edit html/css”

3) Click into “main_style.css”

4) Here locate this code:

#navigation ul li#active a, #navigation a:hover {
border-top: 3px solid #2ec5cc;
}

5) You can change the HEX color code highlighted above to change the color of the strip. You can find your color code here: http://colorpicker.com/

6) Once complete, save your change and re-publish your website