.navbar-inner {
background-color: #000; /* background color will be black for all browsers */
background-image: none;
background-repeat: no-repeat;
filter: none;
}
You can take advantage of such tools as the 颜色渐变编辑器 and create your own gradient colors for all browsers and replace the original colors with your own.
And as i mentioned on the comments, i would not recommend you modifying the bootstrap.css stylesheet directly as all of your changes will be lost once the stylesheet gets updated (current version is V2.0.2) so it is preferred that you include all of your changes inside your own stylesheet, in tandem with the bootstrap.css stylesheet. But remember to overwrite all of the appropriate properties to have consistency across browsers.
Once you have done this, then go to the less folder in the directory and then edit the file variables.less and you can change a lot of variables according to what you need including the color of the navigation bar