UI: Minor tweaks to default theme

Based on feedback from the 'User Feedback' devtalk forum

* More opaque panels for the viewport
* Darker state colors
* Current frame color consistency for MCE

release/datafiles/userdef/userdef_default_theme.c

@@ -107,7 +107,7 @@ const bTheme U_theme_default = {
 			.text_sel = RGBA(0xffffffff),
 			.shaded = 1,
 			.shadetop = -4,
-			.roundness = 0.4f,
+			.roundness = 0.2f,
 		},
 		.wcol_tab = {
 			.outline = RGBA(0x2d2d2dff),
@@ -220,11 +220,11 @@ const bTheme U_theme_default = {
 			.roundness = 0.2f,
 		},
 		.wcol_state = {
-			.inner_anim = RGBA(0x73be4cff),
+			.inner_anim = RGBA(0x53992eff),
 			.inner_anim_sel = RGBA(0x5aa633ff),
-			.inner_key = RGBA(0xf0eb64ff),
+			.inner_key = RGBA(0xb3ae36ff),
 			.inner_key_sel = RGBA(0xd7d34bff),
-			.inner_driven = RGBA(0xb400ffff),
+			.inner_driven = RGBA(0x9000ccff),
 			.inner_driven_sel = RGBA(0x9900e6ff),
 			.inner_overridden = RGBA(0x19c3c300),
 			.inner_overridden_sel = RGBA(0x118f8f00),
@@ -288,8 +288,8 @@ const bTheme U_theme_default = {
 		.button_text = RGBA(0xe5e5e5ff),
 		.button_text_hi = RGBA(0xffffffff),
 		.panelcolors = {
-			.header = RGBA(0x424242cc),
-			.back = RGBA(0x333333b3),
+			.header = RGBA(0x424242e6),
+			.back = RGBA(0x333333f0),
 			.sub_back = RGBA(0x0000003e),
 			.show_header = 1,
 			.show_back = 1,
@@ -900,7 +900,7 @@ const bTheme U_theme_default = {
 		},
 		.strip = RGBA(0x0c0a0a80),
 		.strip_select = RGBA(0xff8c00ff),
-		.cframe = RGBA(0x308837ff),
+		.cframe = RGBA(0x5680c2ff),
 		.handle_auto = RGBA(0x909000ff),
 		.handle_align = RGBA(0x803060ff),
 		.handle_sel_auto = RGBA(0xf0ff40ff),