使功能区背景透明

Question

我发现了这个很棒的ribbon CSS，我一直在用它来进行设计。我快到了。我唯一的问题是，它的设置方式是使用"身体背景色"，最初是蓝色，来制作带状三角形和阴影。。。唯一的问题是我的布局将有一个木制的背景，所以使用颜色来制作丝带是行不通的。

我希望有人能帮助我，或者给我一些关于如何使丝带末端透明而不是蓝色的建议。

我已经为这个问题做了一个jsfiddle

CSS

/*Basic reset*/
* {margin: 0; padding: 0;}
html, body {height: 100%;}
body {
    background-image: url('http://noellesnotes.com/tester/wp-content/themes/ribbons-and-clouds/img/wood_pattern.png');
    text-align: center;
}
.container{
  width:564px;
  height: 500px;
  background: #FFFFFF;
  background-image: url('http://noellesnotes.com/tester/wp-content/themes/ribbons-and-clouds/img/paper_fibers.png');
  margin: 20px auto 20px;
  box-shadow: 3px 3px 3px #555555;
}
h1 {
    display: inline-block;
  width: 600px;
    font-size: 14px;
    line-height: 28px;
    color: #8699A0;
    text-shadow: 0 0 1px #758890;
    margin: 10px 0;
    font-family: arial, verdana;
    outline: none;
    padding: 14px 30px;
    position: relative;
    text-transform: uppercase;
    /*A little shadow for 3d effect*/
    /*Finally another shadow to negate some aspects of the :after element to complete the effect. This drops a shrinked shadow over the :after element with the same color like that of the background. The shadow is shrinked by the same offset amount = 18. And it is moved down by twice the offset amount to cover the entire height of the :after element*/
    box-shadow: 
        0 0 30px 0 rgba(0, 0, 0, 0.1), 
        0 36px 0 -18px #B1E3E2;
}
/*The ribbon ends*/
h1:before {
    content: '';
    position: absolute;
    top: 18px;
    left: -15%;
    z-index: -1;
    width: 130%;
    /*We will be using the triangle logic - 2 sided borders and 0 height. That will create negative triangles on the left and right*/
    height: 0;
    border: 28px solid rgba(0, 0, 0, 0);
    border-left: 28px solid #B1E3E2;
    border-right: 28px solid #B1E3E2;
    /*Same color as the container which is the body in this case*/
}
/*The after pseudo element will negatve the bottom part of the ribbon completing the effect*/
h1:after {
    content: '';
    width: 100%;
    height: 0;
    position: absolute;
    top: 100%; left: 0;
    z-index: -1;
    /*The height of the top border is same as width of the left/right borders for the smoothest effect. The height of the top border is also the same as the offset the :before element has from the top*/
    border-top: 18px solid #99acb2;
    border-left: 18px solid transparent;
    border-right: 18px solid transparent;
}
h1, h1:before {
    /*Some cool multi-background - we will use a combination of 4 backgrounds to create a cool effect*/
    background-image: 
        /*2 grey borders*/
        linear-gradient(
            transparent 8%, 
            rgba(0, 0, 0, 0.1) 8%, 
            rgba(0, 0, 0, 0.1) 14%, 
            transparent 14%, 
            transparent 86%, 
            rgba(0, 0, 0, 0.1) 86%, 
            rgba(0, 0, 0, 0.1) 92%, 
            transparent 92%
        ), 
        /*white gloss gradient*/
        linear-gradient(
            rgba(255, 255, 255, 0.75), 
            rgba(255, 255, 255, 0) 
        ), 
        /*thin stripes*/
        linear-gradient(
            45deg, 
            transparent 40%, 
            rgba(0, 0, 0, 0.1) 40%, 
            rgba(0, 0, 0, 0.1) 60%, 
            transparent 60%
        ), 
        /*white base*/
        linear-gradient(#7ED3F6, #7ED3F6); 
    background-size: 
        cover, /*borders*/
        cover, /*white gloss*/
        4px 4px, /*thin stripes*/
        cover; /*base white*/
}
h1, h1:before, h1:after {
    box-sizing: border-box;
    /*Fix to make the borders appear on the ribbon ends also*/
    background-origin: border-box;
}

提前感谢！

Answer 1

不幸的是，您需要尝试以不同的方式制作此功能区。你会一直遇到的问题是，背景（渐变）总是在你创建的边界剪切下方，所以让这些透明只能显示渐变。除了使用css掩码（只有webkit浏览器实验性地支持）之外，您还必须预先编写大量这些元素，或者查看Canvas元素，或者SVG。你可以查看-webkit mask image:url（"…你的图像…"），但正如我所说，它几乎没有浏览器支持。