CustomWindow.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

#if UNITY_EDITOR
using UnityEditor;
#endif

public class CustomWindow : EditorWindow
{

    string charaName = "Animations";
    
    //WIndow設定
    [MenuItem("Window/CustomWindow")]
    static void Open()
    {
        EditorWindow.GetWindow<CustomWindow>("Custom window");
    }

    void OnGUI()
    {
        printCustomLabel("パラメータ設定", Color.white, Color.black, 18);

        savePath = EditorGUILayout.TextField("名前", savePath);
        if (GUILayout.Button("生成"))
        {
            Debug.Log("Push");
        }
    }

    //Label装飾用のラッパー
    void printCustomLabel(string text, Color textColor, Color backColor, int fontSize, FontStyle fontStyle = FontStyle.Bold)
    {
        Color beforeBackColor = GUI.backgroundColor;
       
        GUIStyle guiStyle = new GUIStyle();
        GUIStyleState styleState = new GUIStyleState();

        styleState.textColor = textColor;
        styleState.background = Texture2D.whiteTexture;
        GUI.backgroundColor = backColor;
        guiStyle.normal = styleState;
        guiStyle.fontSize = fontSize;

        GUILayout.Label(text, guiStyle); //labelFieldだとうまくいかない？
        
        GUI.backgroundColor = beforeBackColor;
    }
}