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+Color Engine (Internal)
+=======================
+Everything you can do with CM-Colors’ internal color classes  
+
+This module provides CM-Colors' internal color engine, including
+the Color and ColorPair classes.
+
+Color
+=====
+Represents a single color in any supported format.
+
+.. autoclass:: cm_colors.color.Color
+    :members: __init__, is_valid, rgb, error, to_hex, to_rgb_string, to_oklch
+    :show-inheritance:
+
+What it does
+------------
+* Parses color input: hex, rgb(), rgba(), HSL, tuples, lists…
+* Converts everything into a clean RGB tuple
+* Handles RGBA compositing if you pass a background
+* Provides helpers (hex, CSS rgb string, OKLCH conversion)
+
+Examples
+--------
+
+Simple parsing:
+
+.. code-block:: python
+  
+    from cm_colors.color import Color
+
+    c = Color("#7B2DC8")
+    print(c.rgb)         # (123, 45, 200)
+    print(c.to_hex())    # "#7b2dc8"
+    print(c.to_rgb_string())  # "rgb(123, 45, 200)"
+
+RGBA with background:
+
+.. code-block:: python
+  
+    c = Color("rgba(100, 150, 200, 0.5)", background_context=Color("#000"))
+    print(c.rgb)  # composited RGB
+
+
+Property Reference
+------------------
+
+**is_valid**  
+    ``True`` if parsing succeeded.
+
+**rgb**  
+    Returns ``(r, g, b)`` or ``None``.
+
+**error**  
+    Returns an error message if invalid.
+
+**to_hex()**  
+    Returns lowercase ``"#rrggbb"``.
+
+**to_rgb_string()**  
+    CSS-style ``"rgb(r, g, b)"``.
+
+**to_oklch()**  
+    Converts to OKLCH color space.
+
+
+ColorPair
+=========
+Holds a text color and a background color, and evaluates readability.
+
+.. autoclass:: cm_colors.color.ColorPair
+    :members: __init__, is_valid, errors, contrast_ratio, wcag_level, delta_e, tune_colors
+    :show-inheritance:
+
+What it does
+------------
+* Parses both text and background colors
+* Computes readability metrics:
+  - WCAG contrast ratio
+  - WCAG level (AA, AAA, FAIL)
+  - Delta E (visual difference)
+* Fixes colors automatically using ``tune_colors()``
+
+Examples
+--------
+
+Check readability:
+
+.. code-block:: python
+
+    pair = ColorPair("#777", "#fff")
+    print(pair.contrast_ratio)
+    print(pair.wcag_level)
+
+Tune colors automatically:
+
+.. code-block:: python
+
+    pair = ColorPair("rgba(100, 100, 100, 0.5)", "white")
+    tuned, is_ok = pair.tune_colors()
+    print(tuned, is_ok)
+
+
+Property Reference
+------------------
+
+**is_valid**  
+    True if both text/background colors are valid.
+
+**errors**  
+    List of error messages.
+
+**contrast_ratio**  
+    Float value — higher = more readable.
+
+**wcag_level**  
+    "FAIL", "AA", "AAA", or "AA Large".
+
+**delta_e**  
+    CIEDE2000 difference between text + background.
+
+**tune_colors(details=False)**  
+    Automatically fixes colors.
+
+    Returns:
+
+    *Simple mode*::
+
+        (tuned_rgb_tuple, success_boolean)
+
+    *Details mode*::
+
+        {
+            "status": True/False,
+            "tuned_text": (r, g, b),
+            "wcag_level": "AA" | "AAA" | "FAIL",
+            "message": "...",
+        }
+
+
+Quick Reference Card
+====================
+
+Parse any color:
+
+.. code-block:: python
+
+    c = Color("#fa0")
+
+Check if valid:
+
+.. code-block:: python
+
+    if not c.is_valid:
+        print(c.error)
+
+Get color formats:
+
+.. code-block:: python
+
+    c.rgb
+    c.to_hex()
+    c.to_rgb_string()
+
+Check color contrast:
+
+.. code-block:: python
+
+    pair = ColorPair("#777", "#fff")
+    pair.contrast_ratio
+    pair.wcag_level
+
+Fix colors:
+
+.. code-block:: python
+
+    tuned, ok = pair.tune_colors()
+
+Calculate perceptual difference:
+
+.. code-block:: python
+
+    pair.delta_e
+
+Convert to OKLCH:
+
+.. code-block:: python
+
+    Color("#ff8040").to_oklch()
+