Update

.idea/deploymentTargetDropDown.xml

@@ -5,6 +5,9 @@
       <entry key="MainActivity">
         <State />
       </entry>
+      <entry key="TimerScreenPreview">
+        <State />
+      </entry>
       <entry key="app">
         <State />
       </entry>

app/src/main/java/com/pomo/myapplication/MainActivity.kt

@@ -36,7 +36,7 @@ class MainActivity : ComponentActivity() {
 
 @Composable
 fun TimerScreen() {
-    var timeLeftInMillis by remember { mutableStateOf(25 * 60 * 1000L) } // 25 minutes
+    var timeLeftInMillis by remember { mutableLongStateOf(25 * 60 * 1000L) } // 25 minutes
     var timerRunning by remember { mutableStateOf(false) }
     val timeFormatted = remember(timeLeftInMillis) {
         val minutes = (timeLeftInMillis / 1000) / 60
@@ -71,6 +71,12 @@ fun TimerScreen() {
         timerRunning = false
     }
 
+    fun setTimer(minutes: Int) {
+        job?.cancel()
+        timeLeftInMillis = minutes * 60 * 1000L
+        timerRunning = false
+    }
+
     val quotes = arrayOf(
         "Don't watch the clock; do what it does. Keep going.",
         "Success is not the key to happiness. Happiness is the key to success.",
@@ -94,7 +100,9 @@ fun TimerScreen() {
             Button(
                 onClick = { startTimer() },
                 enabled = !timerRunning
-            ) {
+
+            )
+            {
                 Text(text = "Start")
             }
             Spacer(modifier = Modifier.width(8.dp))
@@ -109,6 +117,21 @@ fun TimerScreen() {
                 Text(text = "Reset")
             }
         }
+
+        Spacer(modifier = Modifier.height(20.dp))
+        Row {
+            Button(onClick = { setTimer(5) }) {
+                Text(text = "5 min")
+            }
+            Spacer(modifier = Modifier.width(8.dp))
+            Button(onClick = { setTimer(15) }) {
+                Text(text = "15 min")
+            }
+            Spacer(modifier = Modifier.width(8.dp))
+            Button(onClick = { setTimer(25) }) {
+                Text(text = "25 min")
+            }
+        }
     }
 }
 

app/src/main/java/com/pomo/myapplication/ui/theme/Color.kt

@@ -16,7 +16,7 @@ val DarkBackground = Color(0xFF121212)
 val DarkSurface = Color(0xFF121212)
 val DarkOnPrimary = Color(0xFFFFFBFE)
 val DarkOnSecondary = Color(0xFFFFFBFE)
-val DarkOnTertiary = Color(0xFFFFFBFE)
+val DarkOnTertiary = Color(0xFF0040FF)
 val DarkOnBackground = Color.White
 val DarkOnSurface = Color.White
 
@@ -28,3 +28,5 @@ val Pink80 = Color(0xFFEFB8C8)
 val Purple40 = Color(0xFF6650a4)
 val PurpleGrey40 = Color(0xFF625b71)
 val Pink40 = Color(0xFF7D5260)
+
+val DarkBlue = Color(0xFF003366)

app/src/main/java/com/pomo/myapplication/ui/theme/Theme.kt

@@ -21,8 +21,8 @@ import androidx.compose.ui.graphics.Color
 
 
 private val LightColorScheme = lightColorScheme(
-    background = Color(0xFFFFFBFE),
-    surface = Color(0xFFFFFBFE),
+    background = Color(0xFFFFFFFF),
+    surface = Color(0xFF0040FF),
     onPrimary = Color.White,
     onSecondary = Color.White,
     onTertiary = Color.White,