Gnome3 Customization | Change Alt+Tab color

To change the color or transparency of Alt+tab App switcher in Gnome 3, you need to edit the file "/usr/share/gnome-shell/theme/gnome-sll.css"
You can do much if you know css basics.




Open the file

sudo gedit /usr/share/gnome-shell/theme/gnome-sll.css


go to the section

.switcher-list

use search to find it (ctrl + f)

the line

background: rgba(R,G,B,A);


The R,G,B for rgb values of the colour
Change it by referring here

A stands for alpha channel. use a value from  0.0 to 1.0
0 is transparent.

example :

.switcher-list {
    background: rgba(173,255,47,0.5);
    border: 1px solid brown;
    border-radius: 24px;
    padding: 20px;

    font-size: 9pt;
    color: brown;
}

In the example above i have changed the border colour to brown.

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Happy hacking

Gnome3 Customization | Change Icon Size

To change the size of the icons in the activity Tab, you need to customize the file /usr/share/gnome-shell/theme/gnome-shell.css.

open the file in gedit or any text editor you like

sudo gedit /usr/share/gnome-shell/theme/gnome-shell.css

the following section describes the icon size and table structure.

.icon-grid {
    spacing: 36px;
    -shell-grid-item-size: 118px;
}

.icon-grid .overview-icon {
    icon-size: 96px;
}

so to reduce the size of the table , you need to change the entries spacing and -shell-grid-item-size

to reduce the size change the values as follows


.icon-grid {
    spacing: 25px;
    -shell-grid-item-size: 50px;
}

.icon-grid .overview-icon {
    icon-size: 50px;
}



Choose values according to your displaY resolution.

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Happy Hacking