버튼 사이즈는 48dp로,
http://developer.android.com/design/style/metrics-grids.html#48dp-rhythm

단위 변환은 아래와 같이,
http://graphicdesign.stackexchange.com/questions/36482/how-
to-convert-between-android-dp-and-css-px

폰트 사이즈는 CSS로 상대적인 크기로,
https://developer.mozilla.org/en-US/docs/Web/CSS/font-size

https://developer.chrome.com/multidevice/webview/pixelperfect