diff --git a/public/index.php b/public/index.php
index 2ea51e7..20368f6 100644
--- a/public/index.php
+++ b/public/index.php
@@ -58,6 +58,16 @@ if (!function_exists('intervalOverlapSeconds')) {
         return max(0, $end - $start);
     }
 }
+if (!function_exists('intervalDurationSeconds')) {
+    function intervalDurationSeconds(?DateTimeImmutable $start, ?DateTimeImmutable $end): int
+    {
+        if ($start === null || $end === null) {
+            return 0;
+        }
+
+        return max(0, $end->getTimestamp() - $start->getTimestamp());
+    }
+}
 if (!function_exists('planetVisibleIntervalsForDay')) {
     function planetVisibleIntervalsForDay(array $planet, DateTimeImmutable $dayStart, DateTimeImmutable $dayEnd): array
     {
@@ -101,19 +111,27 @@ if (!function_exists('planetVisibilityClass')) {
 
         $nightSeconds = 0;
         $twilightSeconds = 0;
+        $visibleSeconds = 0;
 
         foreach ($intervals as [$from, $to]) {
+            $visibleSeconds += intervalDurationSeconds($from, $to);
             $nightSeconds += intervalOverlapSeconds($from, $to, $astroDusk, $astroDawnNext);
             $twilightSeconds += intervalOverlapSeconds($from, $to, $civilDusk, $astroDusk);
             $twilightSeconds += intervalOverlapSeconds($from, $to, $astroDawnNext, $civilDawnNext);
         }
 
-        if ($nightSeconds > 0) {
-            return ['class' => 'planet-visibility-good', 'label' => 'nachts gut'];
+        if ($visibleSeconds <= 0) {
+            return ['class' => 'planet-visibility-bad', 'label' => 'am Tag'];
         }
 
-        if ($twilightSeconds > 0) {
-            return ['class' => 'planet-visibility-warn', 'label' => 'in der Daemmerung'];
+        $nightRatio = $nightSeconds / $visibleSeconds;
+
+        if ($nightSeconds >= 3600 && $nightRatio >= 0.35) {
+            return ['class' => 'planet-visibility-good', 'label' => 'nachts gut sichtbar'];
+        }
+
+        if (($nightSeconds + $twilightSeconds) > 0) {
+            return ['class' => 'planet-visibility-warn', 'label' => 'nur teilweise nachts / in der Dämmerung'];
         }
 
         return ['class' => 'planet-visibility-bad', 'label' => 'am Tag'];