opera-panel.css

/* move addressbar and bookmarks  to the right */
.toolbar-addressbar.toolbar,.bookmark-bar {margin-left: 34px;} /* if you use panel toggle, make this 44 */

/* create illusion of panel merging into address bar by making panel same color as browser background */
#switch,#panels-container:after {background: var(--colorBg);}

#panels-container:after {border-right: 1px solid var(--colorBg) !important;}

/* move panel buttons down just a tad */
.bookmarks {margin-top: 1px;} /* if you use the bookmarks bar, make this -1 */

/* disable everything after this line if you don't use AFV */
#browser.acc-dark.color-behind-tabs-on #main > .toolbar {background: var(--colorBg);}

#browser.acc-dark.color-behind-tabs-on #main,
#browser.acc-dark.color-behind-tabs-on #switch,
#browser.acc-dark.color-behind-tabs-on #panel_switch,
#browser.acc-dark.color-behind-tabs-on #panels-container:after {
	background: #353945 !important;
}

#panels-container:after {border-right: 1px solid rgba(0,0,0,0.35) !important;}

.acc-dark.color-behind-tabs-on #switch button svg {fill: #d3dae3;}

.theme-light.acc-light #panel_switch:hover,
.theme-light.acc-light #switch button:hover {
	background: var(--colorBgLightIntense) !important;
}

.theme-light.acc-light #switch,
.theme-light.acc-light #panel_switch {
	box-shadow: inset -1px 0 transparent !important;
}

.theme-dark #switch button svg,
.theme-dark #switch button.active svg,
.theme-light.acc-dark.color-behind-tabs-on #switch button svg {
	fill: #d3dae3 !important;
}

#switch button svg,
#switch button.active svg,
.theme-light.acc-dark #switch button.active svg {
    fill: var(--colorFg) !important;
}

.theme-dark #switch .webviewbtn img {background: transparent !important;}

.theme-light.acc-light.color-behind-tabs-off #switch button:hover {background: #fff !important;}