diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index c93e1eb..e670b60 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -24,12 +24,6 @@ jobs:
             os: ubuntu-latest
 
           # Python version testing (Linux)
-          - python: 3.8
-            toxenv: py38
-            os: ubuntu-latest
-          - python: 3.9
-            toxenv: py39
-            os: ubuntu-latest
           - python: "3.10"
             toxenv: py310
             os: ubuntu-latest
@@ -42,12 +36,6 @@ jobs:
           - python: "3.13"
             toxenv: py313
             os: ubuntu-latest
-          - python: pypy-3.8
-            toxenv: pypy38
-            os: ubuntu-latest
-          - python: pypy-3.9
-            toxenv: pypy39
-            os: ubuntu-latest
           - python: pypy-3.10
             toxenv: pypy310
             os: ubuntu-latest
diff --git a/.gitignore b/.gitignore
index 4eac1e6..81ad4ac 100644
--- a/.gitignore
+++ b/.gitignore
@@ -86,8 +86,8 @@ target/
 profile_default/
 ipython_config.py
 
-# pyenv (but we want to track our .python-version file)
-# .python-version
+# pyenv
+.python-version
 
 # pipenv
 #   According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control.
diff --git a/.python-version b/.python-version
deleted file mode 100644
index 2c07333..0000000
--- a/.python-version
+++ /dev/null
@@ -1 +0,0 @@
-3.11
diff --git a/setup.py b/setup.py
index 4d06e32..698d433 100644
--- a/setup.py
+++ b/setup.py
@@ -37,7 +37,7 @@ def get_install_requires():
     packages=find_packages(exclude=["*.tests", "*.tests.*", "tests.*", "tests"]),
     long_description=read("README.rst"),
     install_requires=get_install_requires(),
-    python_requires=">=3.8",
+    python_requires=">=3.10",
     include_package_data=True,
     classifiers=[
         "Topic :: Education",
@@ -46,8 +46,6 @@ def get_install_requires():
         "Intended Audience :: Science/Research",
         "License :: OSI Approved :: BSD License",
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.8",
-        "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
         "Programming Language :: Python :: 3.12",
diff --git a/tilingsgui/menu.py b/tilingsgui/menu.py
index 0d73723..379e582 100644
--- a/tilingsgui/menu.py
+++ b/tilingsgui/menu.py
@@ -23,9 +23,9 @@ class TopMenu(pyglet.event.EventDispatcher, Observer):
     _FONT_SIZE = 20
     _TEXT_COLOR = Color.alpha_extend(Color.BLACK)
     _TEXT_BOX_COLOR = Color.scale_to_01(Color.WHITE)
-    _BACKGROUND_COLOR = Color.BLACK
-    _V_BTN = 118
-    _CTRL_MODIFIER = 18
+    _BACKGROUND_COLOR = Color.scale_to_01(Color.BLACK)
+    _PASTE_KEY = pyglet.window.key.V
+    _PASTE_MOD = pyglet.window.key.MOD_ACCEL
 
     def __init__(
         self,
@@ -97,7 +97,7 @@ def on_key_press(self, symbol: int, modifiers: int) -> bool:
             bool: True if the event is consumed by the handler, false otherwise.
         """
         if self._text_box.has_focus():
-            if symbol == TopMenu._V_BTN and modifiers == TopMenu._CTRL_MODIFIER:
+            if symbol == TopMenu._PASTE_KEY and modifiers & TopMenu._PASTE_MOD:
                 self._text_box.add_text(paste())
                 return True
             if symbol == pyglet.window.key.ESCAPE:
diff --git a/tilingsgui/tplot.py b/tilingsgui/tplot.py
index 7750e5a..3a26da4 100644
--- a/tilingsgui/tplot.py
+++ b/tilingsgui/tplot.py
@@ -43,6 +43,7 @@ class TPlot:
     _HIGHLIGHT_COLOR: ClassVar[Tuple[float, float, float]] = Color.scale_to_01(
         Color.ORANGE
     )
+    _BLACK_COLOR: ClassVar[Tuple[float, float, float]] = Color.scale_to_01(Color.BLACK)
     _EMPTY_COLOR: ClassVar[Tuple[float, float, float]] = Color.scale_to_01(Color.GRAY)
     _SHADED_CELL_COLOR: ClassVar[Tuple[float, float, float]] = Color.scale_to_01(
         Color.GRAY
@@ -347,7 +348,7 @@ def _draw_requirements(self, state: GuiState, mpos: Point) -> None:
             ):
                 pnt = reqlist[0][0]
                 GeoDrawer.draw_circle(
-                    pnt.x, pnt.y, TPlot._PRETTY_POINT_SIZE, Color.BLACK
+                    pnt.x, pnt.y, TPlot._PRETTY_POINT_SIZE, TPlot._BLACK_COLOR
                 )
                 continue
             col = (
@@ -365,12 +366,12 @@ def _draw_requirements(self, state: GuiState, mpos: Point) -> None:
     def _draw_grid(self) -> None:
         """Draw the tiling's grid."""
         t_w, t_h = self.tiling.dimensions
-        for i in range(t_w):
+        for i in range(t_w + 1):
             x = self._w * i / t_w
-            GeoDrawer.draw_line_segment(x, self._h, x, 0, Color.BLACK)
-        for i in range(t_h):
+            GeoDrawer.draw_line_segment(x, self._h, x, 0, TPlot._BLACK_COLOR)
+        for i in range(t_h + 1):
             y = self._h * i / t_h
-            GeoDrawer.draw_line_segment(0, y, self._w, y, Color.BLACK)
+            GeoDrawer.draw_line_segment(0, y, self._w, y, TPlot._BLACK_COLOR)
 
     def to_tikz(self) -> None:
         """Output tikz drawing."""
diff --git a/tilingsgui/widgets.py b/tilingsgui/widgets.py
index 72945cd..a0b8329 100644
--- a/tilingsgui/widgets.py
+++ b/tilingsgui/widgets.py
@@ -25,6 +25,7 @@ def __init__(self, init_text: str, font_size: int, color: RGBA) -> None:
             color (Tuple[float, float, float, float]): The font color.
         """
 
+        self._font_size: int = font_size
         self._batch: pyglet.graphics.Batch = pyglet.graphics.Batch()
         self._document: pyglet.text.document.UnformattedDocument = (
             pyglet.text.document.UnformattedDocument(init_text)
@@ -41,6 +42,7 @@ def __init__(self, init_text: str, font_size: int, color: RGBA) -> None:
                 batch=self._batch,
             )
         )
+        self._layout.content_valign = "center"
         self._caret: pyglet.text.caret.Caret = pyglet.text.caret.Caret(self._layout)
         self._caret.visible = False
 
@@ -54,9 +56,9 @@ def position(self, x: float, y: float, w: float, h: float) -> None:
             h (float): The vertical length of the component.
         """
         self._layout.x = int(x + Text._LEFT_PAD)
-        self._layout.y = int(y - 15)
+        self._layout.y = int(y - self._font_size // 4)
         self._layout.width = int(w - Text._LEFT_PAD)
-        self._layout.height = int(h)
+        self._layout.height = int(h + self._font_size // 4)
 
     def set_focus(self) -> None:
         """Set focus on the input text. This is needed to write to it."""
@@ -168,7 +170,7 @@ def hit_test(self, x: float, y: float) -> bool:
 class Button:
     """A clickable rectangular GUI component."""
 
-    _BUTTON_COLOR: ClassVar[RGB] = Color.GRAY
+    _BUTTON_COLOR: ClassVar[RGB] = Color.scale_to_01(Color.GRAY)
 
     def __init__(
         self, image: str, on_click: Optional[Callable[[], None]] = None
@@ -261,7 +263,7 @@ def _hit_test(self, x: float, y: float) -> bool:
 class ToggleButton(Button):
     """A button that is either on or off."""
 
-    _TOGGLE_COLOR: ClassVar[RGB] = Color.DARK_OLIVE_GREEN
+    _TOGGLE_COLOR: ClassVar[RGB] = Color.scale_to_01(Color.DARK_OLIVE_GREEN)
 
     def __init__(
         self,
diff --git a/tox.ini b/tox.ini
index d2fb7a9..aa99df1 100644
--- a/tox.ini
+++ b/tox.ini
@@ -6,8 +6,8 @@
 [tox]
 envlist =
     flake8, mypy, pylint, black
-    py{38,39,310,311,312,313},
-    pypy{38,39,310}
+    py{310,311,312,313},
+    pypy{310}
 
 [default]
 basepython=python3.11
@@ -15,14 +15,10 @@ basepython=python3.11
 [testenv]
 description = run test
 basepython =
-    py38: python3.8
-    py39: python3.9
     py310: python3.10
     py311: python3.11
     py312: python3.12
     py313: python3.13
-    pypy38: pypy3.8
-    pypy39: pypy3.9
     pypy310: pypy3.10
 deps =
     setuptools