Rainbow text for unity Debug.Log

public static string ToRainbow (this string sourceText)
{
    string finalText = "";

    foreach (char letter in sourceText)
    {
        Color randomColor = new Color(
            Random.Range(0.0f, 1.0f),
            Random.Range(0.0f, 1.0f),
            Random.Range(0.0f, 1.0f)
        );

        if (letter == ' '){
            finalText += letter;
        }
        else
        {
            finalText += string.Format("<color=#{0}>{1}</color>", randomColor.ToHex(), letter);
        }
    }

    return finalText;
}

public static string ToHex (this Color32 sourceColor)
{
    string hex = sourceColor.r.ToString("X2") + sourceColor.g.ToString("X2") + sourceColor.b.ToString("X2");

    return hex;
}