There may be a minor readability issue in Epiphany. To fix it:

(1) Select "Use custom stylesheet" in "Preferences > Font & Style"; and

(2) Create '~/.config/epiphany/user-stylesheet.css' as:

select {
	border-radius: 0 !important;
	border-color: transparent !important;
}

input {
	color: #000 !important;
}


There is a posibillity for changing the background color of the panel for dark ambiance,
useful for a transparency panel with a dark DE background,
Edit the gtkrc file in the gtk-2.0 folder.

change those lines

style "misc-panel"
{
	engine "murrine"
	{
		rgba = FALSE
		roundness=3
	}

	bg[NORMAL]   = "#C2D0BD"  # for the (light) Ambiance background
#	bg[NORMAL]   = "#5A6C5F"  # for the (dark) Ambiance background
	bg[PRELIGHT] = "#AEC6A6" #for the (light) Ambiance background
#	bg[PRELIGHT] = "#C7E3BE" #for the (dark) Ambiance background
	bg[SELECTED] = shade (0.6, @bg_color)  # to be compatible with menus
#	bg[SELECTED] = shade (1.08, @bg_color)  # to be compatible with menus (dark) Ambiance background
	fg[NORMAL]   = "#000000"  # for light panel
#	fg[NORMAL]   = "#FFFFFF"  # for dark panel
#	fg[PRELIGHT] = "#000000"  # for dark panel
#	fg[SELECTED] = "#000000"  # for dark panel

to this ones

style "misc-panel"
{
	engine "murrine"
	{
		rgba = FALSE
		roundness=3
	}

#	bg[NORMAL]   = "#C2D0BD"  # for the (light) Ambiance background
	bg[NORMAL]   = "#5A6C5F"  # for the (dark) Ambiance background
#	bg[PRELIGHT] = "#AEC6A6" #for the (light) Ambiance background
	bg[PRELIGHT] = "#C7E3BE" #for the (dark) Ambiance background
#	bg[SELECTED] = shade (0.6, @bg_color)  # to be compatible with menus (light) Ambiance background
	bg[SELECTED] = shade (1.08, @bg_color)  # to be compatible with menus (dark) Ambiance background
#	fg[NORMAL]   = "#000000"  # for light panel
	fg[NORMAL]   = "#FFFFFF"  # for dark panel
	fg[PRELIGHT] = "#000000"  # for dark panel
	fg[SELECTED] = "#000000"  # for dark panel

Have fun.
