diff --git a/.idea/.name b/.idea/.name
deleted file mode 100644
index 5984d29..0000000
--- a/.idea/.name
+++ /dev/null
@@ -1 +0,0 @@
-Android(MediaConverter
\ No newline at end of file
diff --git a/.idea/gradle.xml b/.idea/gradle.xml
index cdbc250..02c4aa5 100644
--- a/.idea/gradle.xml
+++ b/.idea/gradle.xml
@@ -1,5 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
+  <component name="GradleMigrationSettings" migrationVersion="1" />
   <component name="GradleSettings">
     <option name="linkedExternalProjectsSettings">
       <GradleProjectSettings>
diff --git a/.idea/misc.xml b/.idea/misc.xml
index a7fab1c..6c84484 100644
--- a/.idea/misc.xml
+++ b/.idea/misc.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="ExternalStorageConfigurationManager" enabled="true" />
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_25" project-jdk-name="jbr-25" project-jdk-type="JavaSDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_25" default="true" project-jdk-name="temurin-25" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/build/classes" />
   </component>
   <component name="ProjectType">
diff --git a/app/src/main/java/dev/jasonmross/mediaconverter/convert/ConverterScreen.kt b/app/src/main/java/dev/jasonmross/mediaconverter/convert/ConverterScreen.kt
index 8126d47..f0244f9 100644
--- a/app/src/main/java/dev/jasonmross/mediaconverter/convert/ConverterScreen.kt
+++ b/app/src/main/java/dev/jasonmross/mediaconverter/convert/ConverterScreen.kt
@@ -5,8 +5,11 @@ import androidx.activity.compose.rememberLauncherForActivityResult
 import androidx.activity.result.contract.ActivityResultContracts
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.ExperimentalLayoutApi
+import androidx.compose.foundation.layout.FlowRow
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.rememberScrollState
 import androidx.compose.foundation.verticalScroll
@@ -20,10 +23,11 @@ import androidx.compose.material3.OutlinedButton
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.getValue
+import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.text.style.TextAlign
+import androidx.compose.ui.unit.Dp
 import androidx.compose.ui.unit.dp
-import androidx.compose.foundation.layout.FlowRow
-import androidx.compose.foundation.layout.ExperimentalLayoutApi
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import androidx.lifecycle.viewmodel.compose.viewModel
 import androidx.media3.common.util.UnstableApi
@@ -32,6 +36,17 @@ import dev.jasonmross.mediaconverter.model.OutputFormat
 import dev.jasonmross.mediaconverter.model.QualityTier
 import java.util.Locale
 
+/** Primary actions are taller than the Material default so they read as the main affordance. */
+private val PrimaryButtonHeight: Dp = 56.dp
+
+/**
+ * Horizontal screen inset.
+ *
+ * Deliberately tighter than the vertical inset so a full-width primary button reaches
+ * close to both edges of the display.
+ */
+private val ScreenPadding: Dp = 16.dp
+
 @UnstableApi
 @Composable
 fun ConverterScreen(
@@ -63,95 +78,131 @@ fun ConverterScreen(
     Column(
         modifier = modifier
             .fillMaxSize()
-            .verticalScroll(rememberScrollState())
-            .padding(24.dp),
-        verticalArrangement = Arrangement.spacedBy(16.dp),
+            .padding(horizontal = ScreenPadding, vertical = 24.dp),
     ) {
-        Text("Media Converter", style = MaterialTheme.typography.headlineMedium)
+        Text(
+            "Media Converter",
+            style = MaterialTheme.typography.headlineMedium,
+            modifier = Modifier.padding(bottom = 16.dp),
+        )
+
+        // The empty state is centred in whatever space is left. The working states
+        // scroll instead, since their content can exceed the screen.
+        val body = Modifier.fillMaxWidth().weight(1f)
 
         when (val s = state) {
-            is ConversionState.Idle -> {
+            is ConversionState.Idle -> Column(
+                modifier = body,
+                verticalArrangement = Arrangement.Center,
+                horizontalAlignment = Alignment.CenterHorizontally,
+            ) {
                 Text(
                     "Pick a file to convert.",
                     style = MaterialTheme.typography.bodyMedium,
-                )
-                Button(onClick = { pickInput.launch(arrayOf("*/*")) }) { Text("Choose file") }
-            }
-
-            is ConversionState.Ready -> {
-                FileCard(s.input)
-                FormatPicker(
-                    selected = settings.format,
-                    onSelect = viewModel::setFormat,
-                )
-                QualityPicker(
-                    selected = settings.quality,
-                    onSelect = viewModel::setQuality,
-                )
-                EnginePicker(
-                    selected = settings.enginePreference,
-                    onSelect = viewModel::setEnginePreference,
+                    textAlign = TextAlign.Center,
+                    modifier = Modifier.padding(bottom = 16.dp),
                 )
                 Button(
-                    onClick = {
-                        requestNotifications.launch(Manifest.permission.POST_NOTIFICATIONS)
+                    onClick = { pickInput.launch(arrayOf("*/*")) },
+                    modifier = Modifier
+                        .fillMaxWidth()
+                        .height(PrimaryButtonHeight),
+                ) { Text("Choose file") }
+            }
+
+            else -> Column(
+                modifier = body.verticalScroll(rememberScrollState()),
+                verticalArrangement = Arrangement.spacedBy(16.dp),
+            ) {
+                when (s) {
+                    is ConversionState.Idle -> Unit
+
+                    is ConversionState.Ready -> {
+                        FileCard(s.input)
+                        FormatPicker(settings.format, viewModel::setFormat)
+                        QualityPicker(settings.quality, viewModel::setQuality)
+                        EnginePicker(settings.enginePreference, viewModel::setEnginePreference)
+                        Button(
+                            onClick = {
+                                requestNotifications.launch(Manifest.permission.POST_NOTIFICATIONS)
+                            },
+                            modifier = Modifier.fillMaxWidth().height(PrimaryButtonHeight),
+                        ) { Text("Convert") }
+                        OutlinedButton(
+                            onClick = { pickInput.launch(arrayOf("*/*")) },
+                            modifier = Modifier.fillMaxWidth(),
+                        ) { Text("Choose a different file") }
+                    }
+
+                    is ConversionState.Converting -> {
+                        FileCard(s.input)
+                        Text("Converting… ${s.percent}%")
+                        LinearProgressIndicator(
+                            progress = { s.percent / 100f },
+                            modifier = Modifier.fillMaxWidth(),
+                        )
+                        OutlinedButton(
+                            onClick = viewModel::cancel,
+                            modifier = Modifier.fillMaxWidth(),
+                        ) { Text("Cancel") }
+                    }
+
+                    is ConversionState.Waiting -> {
+                        FileCard(s.input)
+                        Text(
+                            "Paused. The system limits background media processing to " +
+                                "six hours a day, so this will resume automatically.",
+                            style = MaterialTheme.typography.bodyMedium,
+                        )
+                        OutlinedButton(
+                            onClick = viewModel::cancel,
+                            modifier = Modifier.fillMaxWidth(),
+                        ) { Text("Cancel") }
+                    }
+
+                    is ConversionState.Converted -> {
+                        FileCard(s.input)
+                        Text(
+                            "Done — ${formatBytes(s.staged.length())} output.",
+                            style = MaterialTheme.typography.bodyMedium,
+                        )
+                        if (s.routeReason.isNotBlank()) {
+                            // Surfacing the routing decision rather than hiding it: it
+                            // explains why a job was slow, and makes the software
+                            // fallback visible.
+                            AssistChip(onClick = {}, label = { Text(s.routeReason) })
+                        }
+                        Button(
+                            onClick = { chooseDestination.launch(viewModel.suggestedOutputName()) },
+                            modifier = Modifier.fillMaxWidth().height(PrimaryButtonHeight),
+                        ) { Text("Save file") }
+                        OutlinedButton(
+                            onClick = viewModel::reset,
+                            modifier = Modifier.fillMaxWidth(),
+                        ) { Text("Start over") }
+                    }
+
+                    is ConversionState.Saved -> {
+                        Text("Saved ${s.displayName}.", style = MaterialTheme.typography.bodyLarge)
+                        Button(
+                            onClick = viewModel::reset,
+                            modifier = Modifier.fillMaxWidth().height(PrimaryButtonHeight),
+                        ) { Text("Convert another") }
+                    }
+
+                    is ConversionState.Failed -> {
+                        Text(
+                            s.message,
+                            color = MaterialTheme.colorScheme.error,
+                            style = MaterialTheme.typography.bodyMedium,
+                        )
+                        Button(
+                            onClick = viewModel::reset,
+                            modifier = Modifier.fillMaxWidth().height(PrimaryButtonHeight),
+                        ) { Text("Start over") }
                     }
-                ) { Text("Convert") }
-                OutlinedButton(onClick = { pickInput.launch(arrayOf("*/*")) }) {
-                    Text("Choose a different file")
                 }
             }
-
-            is ConversionState.Converting -> {
-                FileCard(s.input)
-                Text("Converting… ${s.percent}%")
-                LinearProgressIndicator(
-                    progress = { s.percent / 100f },
-                    modifier = Modifier.fillMaxWidth(),
-                )
-                OutlinedButton(onClick = viewModel::cancel) { Text("Cancel") }
-            }
-
-            is ConversionState.Waiting -> {
-                FileCard(s.input)
-                Text(
-                    "Paused. The system limits background media processing to six " +
-                        "hours a day, so this will resume automatically.",
-                    style = MaterialTheme.typography.bodyMedium,
-                )
-                OutlinedButton(onClick = viewModel::cancel) { Text("Cancel") }
-            }
-
-            is ConversionState.Converted -> {
-                FileCard(s.input)
-                Text(
-                    "Done — ${formatBytes(s.staged.length())} output.",
-                    style = MaterialTheme.typography.bodyMedium,
-                )
-                if (s.routeReason.isNotBlank()) {
-                    // Surfacing the routing decision rather than hiding it: it explains
-                    // why a job was slow, and makes the software fallback visible.
-                    AssistChip(onClick = {}, label = { Text(s.routeReason) })
-                }
-                Button(onClick = { chooseDestination.launch(viewModel.suggestedOutputName()) }) {
-                    Text("Save file")
-                }
-                OutlinedButton(onClick = viewModel::reset) { Text("Start over") }
-            }
-
-            is ConversionState.Saved -> {
-                Text("Saved ${s.displayName}.", style = MaterialTheme.typography.bodyLarge)
-                Button(onClick = viewModel::reset) { Text("Convert another") }
-            }
-
-            is ConversionState.Failed -> {
-                Text(
-                    s.message,
-                    color = MaterialTheme.colorScheme.error,
-                    style = MaterialTheme.typography.bodyMedium,
-                )
-                Button(onClick = viewModel::reset) { Text("Start over") }
-            }
         }
     }
 }