change the thickness of the editText

As I can leave the edittext bar as the first field that looks thicker, I saw several options but none worked and I do not know if it is from the focus or that. The difference is minimal but it shows because the focus enlarges the line

<TextInputLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            app:hintTextAppearance="@style/MyHintText">
            <EditText
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:hint="@string/amount"
                android:inputType="number"
                android:textColor="@color/greenDark"
                android:maxLength="10"
                android:textSize="@dimen/simple_text_size_small"
                android:theme="@style/MyEditText" />
        </TextInputLayout>