Tạo khung cho ảnh trong suốt bằng Css

sử dụng ảnh nhỏ trong suốt làm nền  sau đó dùng padding  lùi vào tạo viền.

<style>
body{background:#2EAF4C url(https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi1H1Io0EhTA-xhH7jCHkVZwfu2pvGWEJRvm-0FxTuy-Jz3lpV8DRO4P3fDup-iwEikQYYgOMOZL3VPmMZv4Lbb0kZ4I4bWldH9iLc6OEIfqz60WL1DkDGRWj4N4H-fpNPIihDjSUHB72Ts/s1600/Windows_7_2.jpg) repeat fixed center top;color:#FFF;font-family:}
img {  background: url("https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiLU1lLFxDEc5jakbLYV15BuJiGukQaJm-ZAl-kC1pN4DV_d88WthvCK0pvqmQWPatmV3xTVkvF7BTmoejeKKNWtajKng-_zCs7BuqRYeP1i94mj9SIkZls7Ahr9Zupv2ri1XFmjfjjWVJc/s1600/black.png") repeat scroll left top transparent;    border: medium none;    margin-top: 50px;    padding: 15px;}
</style>

tham số padding :15px là  độ dày của khung  ảnh .
sử dụng
<img src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi1H1Io0EhTA-xhH7jCHkVZwfu2pvGWEJRvm-0FxTuy-Jz3lpV8DRO4P3fDup-iwEikQYYgOMOZL3VPmMZv4Lbb0kZ4I4bWldH9iLc6OEIfqz60WL1DkDGRWj4N4H-fpNPIihDjSUHB72Ts/s1600/Windows_7_2.jpg" width="300" height="200">