feat: Add horizon theme (#313)

Co-authored-by: Jonah Lawrence <[email protected]>

Author: miguelsotobaez

docs/themes.md

@@ -94,6 +94,7 @@ You can also try out and customize these themes on the [Demo Site](https://githu
 |             `sea`             | ![image](https://user-images.githubusercontent.com/103951737/184303266-0e5f8a25-bfeb-4876-abf1-91a38ca87680.png) |
 |          `sea-dark`           | ![image](https://user-images.githubusercontent.com/103951737/184301879-953370eb-e61a-4e0f-abf4-7029c336e8f1.png) |
 |         `violet-dark`         | ![image](https://user-images.githubusercontent.com/103951737/184529784-05de7e57-b939-42f7-9852-345fa191c343.png) |
+|           `horizon`           |  ![image](https://user-images.githubusercontent.com/3828247/184559656-e1f1b290-0a44-45cc-9681-010577386760.png)  |
 
 ### Can't find the theme you like?
 

src/themes.php

@@ -1058,4 +1058,16 @@
         "sideLabels" => "#FF0089",
         "dates" => "#FF0089",
     ],
+    "horizon" => [
+        "background" => "#1C1E26",
+        "border" => "#1C1E26",
+        "stroke" => "#FAB795",
+        "ring" => "#E95678",
+        "fire" => "#E95678",
+        "currStreakNum" => "#59E1E3",
+        "sideNums" => "#59E1E3",
+        "currStreakLabel" => "#23BD87",
+        "sideLabels" => "#23BD87",
+        "dates" => "#FAB795",
+    ],
 ];