diff --git a/briar-android/src/main/java/org/briarproject/briar/android/contact/add/remote/NicknameFragment.java b/briar-android/src/main/java/org/briarproject/briar/android/contact/add/remote/NicknameFragment.java
index b084c061d..acb5da8c2 100644
--- a/briar-android/src/main/java/org/briarproject/briar/android/contact/add/remote/NicknameFragment.java
+++ b/briar-android/src/main/java/org/briarproject/briar/android/contact/add/remote/NicknameFragment.java
@@ -55,6 +55,7 @@ public class NicknameFragment extends BaseFragment {
 
 	private TextInputLayout contactNameLayout;
 	private TextInputEditText contactNameInput;
+	private BriarButton addButton;
 
 	@Override
 	public String getUniqueTag() {
@@ -91,7 +92,7 @@ public class NicknameFragment extends BaseFragment {
 		contactNameLayout = v.findViewById(R.id.contactNameLayout);
 		contactNameInput = v.findViewById(R.id.contactNameInput);
 
-		BriarButton addButton = v.findViewById(R.id.addButton);
+		addButton = v.findViewById(R.id.addButton);
 		addButton.setOnClickListener(view -> onAddButtonClicked());
 
 		return v;
@@ -112,7 +113,7 @@ public class NicknameFragment extends BaseFragment {
 	@Nullable
 	private String getNicknameOrNull() {
 		Editable text = contactNameInput.getText();
-		if (text == null || text.toString().trim().length() == 0) {
+		if (text == null || text.toString().trim().isEmpty()) {
 			contactNameLayout.setError(getString(R.string.nickname_missing));
 			contactNameInput.requestFocus();
 			return null;
@@ -129,7 +130,10 @@ public class NicknameFragment extends BaseFragment {
 
 	private void onAddButtonClicked() {
 		String name = getNicknameOrNull();
-		if (name == null) return;  // invalid nickname
+		if (name == null) { // invalid nickname
+			addButton.reset();
+			return;
+		}
 
 		LifecycleOwner owner = getViewLifecycleOwner();
 		viewModel.getAddContactResult().observe(owner, result -> {
diff --git a/briar-android/src/main/java/org/briarproject/briar/android/util/BriarSnackbarBuilder.java b/briar-android/src/main/java/org/briarproject/briar/android/util/BriarSnackbarBuilder.java
index 0586e5a5f..8ff4c2058 100644
--- a/briar-android/src/main/java/org/briarproject/briar/android/util/BriarSnackbarBuilder.java
+++ b/briar-android/src/main/java/org/briarproject/briar/android/util/BriarSnackbarBuilder.java
@@ -26,7 +26,9 @@ public class BriarSnackbarBuilder {
 
 	public Snackbar make(View view, CharSequence text, int duration) {
 		Snackbar s = Snackbar.make(view, text, duration);
-		s.getView().setBackgroundResource(backgroundResId);
+		s.setBackgroundTint(getColor(view.getContext(), backgroundResId));
+		s.setTextColor(
+				getColor(view.getContext(), R.color.md_theme_onSecondary));
 		if (onClickListener != null) {
 			s.setActionTextColor(getColor(view.getContext(),
 					R.color.briar_button_text_positive));
diff --git a/briar-android/src/main/java/org/briarproject/briar/android/view/BriarButton.java b/briar-android/src/main/java/org/briarproject/briar/android/view/BriarButton.java
index 7247cc935..1a5b6b567 100644
--- a/briar-android/src/main/java/org/briarproject/briar/android/view/BriarButton.java
+++ b/briar-android/src/main/java/org/briarproject/briar/android/view/BriarButton.java
@@ -49,7 +49,7 @@ public class BriarButton extends FrameLayout {
 
 		ContextThemeWrapper wrapper = new ContextThemeWrapper(context, style);
 		button = isInEditMode() ? new MaterialButton(context) :
-				new MaterialButton(wrapper);
+				new MaterialButton(wrapper, null, style);
 		button.setText(text);
 		addView(button);
 		progressBar = findViewById(R.id.briar_button_progress_bar);
diff --git a/briar-android/src/main/res/color/button_text.xml b/briar-android/src/main/res/color/button_text.xml
deleted file mode 100644
index 1f1c03e9f..000000000
--- a/briar-android/src/main/res/color/button_text.xml
+++ /dev/null
@@ -1,9 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<selector
-	xmlns:android="http://schemas.android.com/apk/res/android">
-	<item
-		android:color="@color/briar_button_text_disabled"
-		android:state_enabled="false"/>
-	<item
-		android:color="#ffffffff"/>
-</selector>
\ No newline at end of file
diff --git a/briar-android/src/main/res/drawable-v21/button_outline.xml b/briar-android/src/main/res/drawable-v21/button_outline.xml
deleted file mode 100644
index d7a4382c2..000000000
--- a/briar-android/src/main/res/drawable-v21/button_outline.xml
+++ /dev/null
@@ -1,7 +0,0 @@
-<ripple xmlns:android="http://schemas.android.com/apk/res/android"
-	android:color="?attr/colorControlHighlight">
-	<item
-		android:id="@android:id/mask"
-		android:drawable="@drawable/button_outline_mask" />
-	<item android:drawable="@drawable/button_outline_background" />
-</ripple>
diff --git a/briar-android/src/main/res/drawable-v21/button_outline_background.xml b/briar-android/src/main/res/drawable-v21/button_outline_background.xml
deleted file mode 100644
index 960d21db4..000000000
--- a/briar-android/src/main/res/drawable-v21/button_outline_background.xml
+++ /dev/null
@@ -1,19 +0,0 @@
-<inset xmlns:android="http://schemas.android.com/apk/res/android"
-	android:insetLeft="4dp"
-	android:insetTop="6dp"
-	android:insetRight="4dp"
-	android:insetBottom="6dp">
-	<shape
-		android:shape="rectangle">
-		<corners android:radius="2dp" />
-		<solid android:color="@android:color/transparent" />
-		<stroke
-			android:width="1dp"
-			android:color="@color/briar_button_outline" />
-		<padding
-			android:bottom="4dp"
-			android:left="8dp"
-			android:right="8dp"
-			android:top="4dp" />
-	</shape>
-</inset>
diff --git a/briar-android/src/main/res/drawable-v21/button_outline_mask.xml b/briar-android/src/main/res/drawable-v21/button_outline_mask.xml
deleted file mode 100644
index 88b29c7a2..000000000
--- a/briar-android/src/main/res/drawable-v21/button_outline_mask.xml
+++ /dev/null
@@ -1,19 +0,0 @@
-<inset xmlns:android="http://schemas.android.com/apk/res/android"
-	android:insetLeft="4dp"
-	android:insetTop="6dp"
-	android:insetRight="4dp"
-	android:insetBottom="6dp">
-	<shape
-		android:shape="rectangle">
-		<corners android:radius="2dp" />
-		<solid android:color="@android:color/white" />
-		<stroke
-			android:width="1dp"
-			android:color="@android:color/white" />
-		<padding
-			android:bottom="4dp"
-			android:left="8dp"
-			android:right="8dp"
-			android:top="4dp" />
-	</shape>
-</inset>
diff --git a/briar-android/src/main/res/drawable/button_outline.xml b/briar-android/src/main/res/drawable/button_outline.xml
deleted file mode 100644
index 795b3fdca..000000000
--- a/briar-android/src/main/res/drawable/button_outline.xml
+++ /dev/null
@@ -1,16 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
-	<item
-		android:bottom="6dp"
-		android:left="4dp"
-		android:right="4dp"
-		android:top="6dp">
-		<shape android:shape="rectangle">
-			<corners android:radius="2dp" />
-			<solid android:color="@android:color/transparent" />
-			<stroke
-				android:width="1dp"
-				android:color="@color/briar_button_outline" />
-		</shape>
-	</item>
-</layer-list>
\ No newline at end of file
diff --git a/briar-android/src/main/res/layout/fragment_hotspot_intro.xml b/briar-android/src/main/res/layout/fragment_hotspot_intro.xml
index 0789c5fc5..d8017ddda 100644
--- a/briar-android/src/main/res/layout/fragment_hotspot_intro.xml
+++ b/briar-android/src/main/res/layout/fragment_hotspot_intro.xml
@@ -61,7 +61,7 @@
 			android:layout_marginHorizontal="@dimen/margin_large"
 			android:text="@string/hotspot_button_start_sharing"
 			app:icon="@drawable/ic_wifi_tethering"
-			app:iconTint="@color/button_text"
+			app:iconTint="?attr/colorOnPrimary"
 			app:layout_constraintBottom_toBottomOf="parent"
 			app:layout_constraintEnd_toEndOf="parent"
 			app:layout_constraintStart_toStartOf="parent"
diff --git a/briar-android/src/main/res/layout/fragment_hotspot_tabs.xml b/briar-android/src/main/res/layout/fragment_hotspot_tabs.xml
index 9ccf1cb78..ed6ee1088 100644
--- a/briar-android/src/main/res/layout/fragment_hotspot_tabs.xml
+++ b/briar-android/src/main/res/layout/fragment_hotspot_tabs.xml
@@ -78,7 +78,7 @@
 		android:layout_marginTop="6dp"
 		android:text="@string/hotspot_button_connected"
 		app:icon="@drawable/ic_check_white"
-		app:iconTint="@color/button_text"
+		app:iconTint="?attr/colorOnPrimary"
 		app:layout_constraintBottom_toTopOf="@+id/stopButton"
 		app:layout_constraintEnd_toEndOf="parent"
 		app:layout_constraintStart_toStartOf="parent"
diff --git a/briar-android/src/main/res/layout/fragment_mailbox_setup_download.xml b/briar-android/src/main/res/layout/fragment_mailbox_setup_download.xml
index aa49a5893..b17011be0 100644
--- a/briar-android/src/main/res/layout/fragment_mailbox_setup_download.xml
+++ b/briar-android/src/main/res/layout/fragment_mailbox_setup_download.xml
@@ -54,7 +54,7 @@
 		android:layout_marginHorizontal="@dimen/margin_large"
 		android:text="@string/mailbox_setup_button_scan"
 		app:icon="@drawable/ic_qr_code"
-		app:iconTint="@color/button_text"
+		app:iconTint="?attr/colorOnPrimary"
 		app:layout_constraintBottom_toBottomOf="parent"
 		app:layout_constraintEnd_toEndOf="parent"
 		app:layout_constraintStart_toStartOf="parent"
diff --git a/briar-android/src/main/res/layout/image_preview.xml b/briar-android/src/main/res/layout/image_preview.xml
index 83bd2271e..93a38cdc0 100644
--- a/briar-android/src/main/res/layout/image_preview.xml
+++ b/briar-android/src/main/res/layout/image_preview.xml
@@ -38,13 +38,15 @@
 		android:layout_marginEnd="8dp"
 		android:layout_marginRight="8dp"
 		android:layout_marginBottom="8dp"
-		app:backgroundTint="@color/briar_accent"
+		android:contentDescription="@string/close"
+		app:backgroundTint="?colorSecondary"
 		app:fabCustomSize="26dp"
 		app:layout_constraintBottom_toBottomOf="parent"
 		app:layout_constraintEnd_toEndOf="parent"
 		app:layout_constraintTop_toTopOf="parent"
 		app:layout_constraintVertical_bias="0"
 		app:maxImageSize="18dp"
-		app:srcCompat="@drawable/ic_close" />
+		app:srcCompat="@drawable/ic_close"
+		app:tint="?colorOnSecondary" />
 
 </merge>
diff --git a/briar-android/src/main/res/values-night/color.xml b/briar-android/src/main/res/values-night/color.xml
index c59204414..fee652a4a 100644
--- a/briar-android/src/main/res/values-night/color.xml
+++ b/briar-android/src/main/res/values-night/color.xml
@@ -3,7 +3,6 @@
 	<color name="briar_primary">@color/briar_night_800</color>
 	<color name="briar_accent">@color/briar_lime_600</color>
 
-	<color name="preference_category">@color/briar_accent</color>
 	<color name="preference_category_background">@color/briar_night_950</color>
 
 	<color name="color_primary">@android:color/white</color>
@@ -18,7 +17,6 @@
 	<color name="card_background">@color/briar_night_800</color>
 	<color name="item_background_highlight">@color/briar_night_700</color>
 
-	<color name="briar_button_background_color">@color/briar_night_500</color>
 	<color name="briar_button_text_neutral">@color/briar_blue_400</color>
 	<color name="briar_button_text_disabled">#23cccccc</color>
 
@@ -33,45 +31,6 @@
 	<color name="il_orange">@color/briar_orange_400</color>
 	<color name="il_red">@color/briar_red_500_new</color>
 
-	<color name="md_theme_secondaryContainer">#3E506B</color>
-	<color name="md_theme_onSecondaryContainer">#E7EFFF</color>
-	<color name="md_theme_tertiary">#E4FFE2</color>
-	<color name="md_theme_onTertiary">#003915</color>
-	<color name="md_theme_tertiaryContainer">#3BEA75</color>
-	<color name="md_theme_onTertiaryContainer">#00451B</color>
-	<color name="md_theme_error">#FFB4AB</color>
-	<color name="md_theme_onError">#690005</color>
-	<color name="md_theme_errorContainer">#D01B1F</color>
-	<color name="md_theme_onErrorContainer">#FFFFFF</color>
-	<color name="md_theme_background">#11150A</color>
 	<color name="md_theme_onBackground">#E0E4D2</color>
-	<color name="md_theme_surface">#11150A</color>
 	<color name="md_theme_onSurface">#E0E4D2</color>
-	<color name="md_theme_surfaceVariant">#424936</color>
-	<color name="md_theme_onSurfaceVariant">#C2CAB0</color>
-	<color name="md_theme_outline">#8C947C</color>
-	<color name="md_theme_outlineVariant">#424936</color>
-	<color name="md_theme_scrim">#000000</color>
-	<color name="md_theme_inverseSurface">#E0E4D2</color>
-	<color name="md_theme_inverseOnSurface">#2E3226</color>
-	<color name="md_theme_inversePrimary">#446900</color>
-	<color name="md_theme_primaryFixed">#B2F746</color>
-	<color name="md_theme_onPrimaryFixed">#121F00</color>
-	<color name="md_theme_primaryFixedDim">#98DA27</color>
-	<color name="md_theme_onPrimaryFixedVariant">#334F00</color>
-	<color name="md_theme_secondaryFixed">#D4E3FF</color>
-	<color name="md_theme_onSecondaryFixed">#071C34</color>
-	<color name="md_theme_secondaryFixedDim">#B5C8E7</color>
-	<color name="md_theme_onSecondaryFixedVariant">#364862</color>
-	<color name="md_theme_tertiaryFixed">#66FF8E</color>
-	<color name="md_theme_onTertiaryFixed">#002109</color>
-	<color name="md_theme_tertiaryFixedDim">#30E36F</color>
-	<color name="md_theme_onTertiaryFixedVariant">#005321</color>
-	<color name="md_theme_surfaceDim">#11150A</color>
-	<color name="md_theme_surfaceBright">#363B2E</color>
-	<color name="md_theme_surfaceContainerLowest">#0B1006</color>
-	<color name="md_theme_surfaceContainerLow">#191D12</color>
-	<color name="md_theme_surfaceContainer">#1D2116</color>
-	<color name="md_theme_surfaceContainerHigh">#272C1F</color>
-	<color name="md_theme_surfaceContainerHighest">#32362A</color>
 </resources>
diff --git a/briar-android/src/main/res/values/color.xml b/briar-android/src/main/res/values/color.xml
index e87d5f56b..9b4848c90 100644
--- a/briar-android/src/main/res/values/color.xml
+++ b/briar-android/src/main/res/values/color.xml
@@ -75,15 +75,12 @@
 	<color name="briar_text_secondary_inverse">#b4ffffff</color>
 	<color name="briar_text_tertiary_inverse">#80ffffff</color>
 
-	<color name="preference_category">@color/briar_night_500</color>
 	<color name="preference_category_background">@color/window_background</color>
 
-	<color name="briar_button_background_color">@color/briar_accent</color>
 	<color name="briar_button_text_positive">@color/briar_blue_400</color>
 	<color name="briar_button_text_neutral">@color/briar_night_500</color>
 	<color name="briar_button_text_negative">@color/briar_red_500</color>
 	<color name="briar_button_text_disabled">#28000000</color>
-	<color name="briar_button_outline">@android:color/secondary_text_dark</color>
 
 	<color name="thread_indicator">@color/briar_gray_500</color>
 	<color name="thread_item_background">@color/window_background</color>
@@ -97,48 +94,10 @@
 	<color name="md_theme_onPrimary">@color/briar_lime_950</color>
 	<color name="md_theme_primaryContainer">@color/briar_night_700</color>
 	<color name="md_theme_onPrimaryContainer">@android:color/white</color>
+	<color name="md_theme_inversePrimary">#98DA27</color>
 	<color name="md_theme_secondary">@color/briar_night_700</color>
 	<color name="md_theme_onSecondary">@android:color/white</color>
 
-	<color name="md_theme_secondaryContainer">#576985</color>
-	<color name="md_theme_onSecondaryContainer">#FFFFFF</color>
-	<color name="md_theme_tertiary">#006E2F</color>
-	<color name="md_theme_onTertiary">#FFFFFF</color>
-	<color name="md_theme_tertiaryContainer">#4CF780</color>
-	<color name="md_theme_onTertiaryContainer">#004E1F</color>
-	<color name="md_theme_error">#A0000E</color>
-	<color name="md_theme_onError">#FFFFFF</color>
-	<color name="md_theme_errorContainer">#DC2626</color>
-	<color name="md_theme_onErrorContainer">#FFFFFF</color>
-	<color name="md_theme_background">#F7FBE8</color>
 	<color name="md_theme_onBackground">#191D12</color>
-	<color name="md_theme_surface">#F7FBE8</color>
 	<color name="md_theme_onSurface">#191D12</color>
-	<color name="md_theme_surfaceVariant">#DEE6CB</color>
-	<color name="md_theme_onSurfaceVariant">#424936</color>
-	<color name="md_theme_outline">#727A64</color>
-	<color name="md_theme_outlineVariant">#C2CAB0</color>
-	<color name="md_theme_scrim">#000000</color>
-	<color name="md_theme_inverseSurface">#2E3226</color>
-	<color name="md_theme_inverseOnSurface">#EFF3E0</color>
-	<color name="md_theme_inversePrimary">#98DA27</color>
-	<color name="md_theme_primaryFixed">#B2F746</color>
-	<color name="md_theme_onPrimaryFixed">#121F00</color>
-	<color name="md_theme_primaryFixedDim">#98DA27</color>
-	<color name="md_theme_onPrimaryFixedVariant">#334F00</color>
-	<color name="md_theme_secondaryFixed">#D4E3FF</color>
-	<color name="md_theme_onSecondaryFixed">#071C34</color>
-	<color name="md_theme_secondaryFixedDim">#B5C8E7</color>
-	<color name="md_theme_onSecondaryFixedVariant">#364862</color>
-	<color name="md_theme_tertiaryFixed">#66FF8E</color>
-	<color name="md_theme_onTertiaryFixed">#002109</color>
-	<color name="md_theme_tertiaryFixedDim">#30E36F</color>
-	<color name="md_theme_onTertiaryFixedVariant">#005321</color>
-	<color name="md_theme_surfaceDim">#D8DCCA</color>
-	<color name="md_theme_surfaceBright">#F7FBE8</color>
-	<color name="md_theme_surfaceContainerLowest">#FFFFFF</color>
-	<color name="md_theme_surfaceContainerLow">#F2F6E3</color>
-	<color name="md_theme_surfaceContainer">#ECF0DD</color>
-	<color name="md_theme_surfaceContainerHigh">#E6EAD8</color>
-	<color name="md_theme_surfaceContainerHighest">#E0E4D2</color>
 </resources>
diff --git a/briar-android/src/main/res/values/themes.xml b/briar-android/src/main/res/values/themes.xml
index 60cfd472a..e8e1a57b4 100644
--- a/briar-android/src/main/res/values/themes.xml
+++ b/briar-android/src/main/res/values/themes.xml
@@ -12,6 +12,7 @@
 		<item name="colorOnBackground">@color/md_theme_onBackground</item>
 		<item name="colorSurface">@color/card_background</item>
 		<item name="colorOnSurface">@color/md_theme_onSurface</item>
+		<item name="colorError">@color/briar_red_600</item>
 		<item name="android:statusBarColor">#000000</item>
 
 		<item name="android:windowBackground">@color/window_background</item>