Demo

Lambda Link! Hey! Listen! With a background color With a background image With a little picture With a big picture

Code

Ok, I'm sorry, this code may be a little scary. But it's not! It's just… long and a bit exhaustive.

In short: the "3D" effect is practicly the same as on the buttons in Firefox Addons website, with a not-blurred inset box-shadow ; the glowing effect is achieved with a ::before pseudo-element with a white-to-transparent gradient. That's all =P

.gb {
    display: inline-block;
    vertical-align:bottom;
    text-decoration: none;
    -moz-text-shadow: 1px 1px 3px rgba(0,0,0,0.5);
    text-shadow: 1px 1px 3px rgba(0,0,0,0.5);
    color: #000;
    min-width:5em;
    width:auto;
    max-width:90%;
    line-height: 2em;
    text-align: center;
    border: none;
    -moz-border-radius : .5em;
    border-radius : .5em;
    margin:.5em;
    padding: 1em;
    position: relative;
    z-index:1;
    -moz-box-shadow: 0 10px 10px rgba(0, 0, 0, .1), 0 -4px  rgba(0, 0, 0, 0.1) inset, 0 -4px 1px 1px rgba(255,255,255,0.2) inset;
    box-shadow: 0 10px 10px rgba(128, 128, 128, .1), 0 -4px  rgba(0, 0, 0, 0.1) inset, 0 -4px 1px 1px rgba(255,255,255,0.2) inset;
    overflow: hidden;
    -moz-transition: box-shadow 0.2s linear;
    -webkit-transition:  box-shadow 0.2s linear;
    -o-transition:  box-shadow 0.2s linear;
    -ms-transition:  box-shadow 0.2s linear;
    transition:  box-shadow 0.2s linear;
    -moz-box-sizing : border-box;
    -webkit-box-sizing: border-box;
    box-sizing : border-box;
    background: #d5d5d5;
}

.gb:hover,
.gb:focus {
    -moz-box-shadow: 0 2px 10px rgba(0, 0, 0, .1), 0 -4px  rgba(0, 0, 0, 0.1) inset, 0 -4px 1px 1px rgba(255,255,255,0.2) inset;
    box-shadow: 0 2px 10px rgba(0, 0, 0, .1), 0 -4px  rgba(0, 0, 0, 0.1) inset, 0 -4px 1px 1px rgba(255,255,255,0.2) inset;
}

.gb:active {
    -moz-box-shadow: 0 0px 5px rgba(0, 0, 0, .1), 0 -4px  rgba(0, 0, 0, 0.1) inset, 0 -4px 1px 1px rgba(255,255,255,0.2) inset;
    box-shadow: 0 0px 5px rgba(0, 0, 0, .1), 0 -4px  rgba(0, 0, 0, 0.1) inset, 0 -4px 1px 1px rgba(255,255,255,0.2) inset;
}

.gb::after {
    content:"";
    color : #ddd;
    -moz-text-shadow: -1px -1px  1px rgba(0,0,0,0.5); 
    text-shadow: -1px -1px  1px rgba(0,0,0,0.5); 
    position:absolute;
    left:1px;
    right:1px;
    top:1px;
    bottom:50%;
    -moz-border-bottom-left-radius: 6px;
    -moz-border-bottom-right-radius: 6px;
    -moz-border-top-left-radius: inherit;
    -moz-border-top-right-radius: inherit;
    border-bottom-left-radius: 6px;
    border-bottom-right-radius: 6px;
    border-top-left-radius: inherit;
    border-top-right-radius: inherit;
    z-index : 10;
    background: -moz-linear-gradient(top, rgba(255,255,255,0.8) 0%, rgba(255,255,255,0.2) 100%);  /*FF3.6+ */
    background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,rgba(255,255,255,0.8)), color-stop(100%,rgba(255,255,255,0.2))); /* Chrome,Safari4+ */
    background: -webkit-linear-gradient(top, rgba(255,255,255,0.8) 0%,rgba(255,255,255,0.2) 100%); /* Chrome10+,Safari5.1+ */
    background: -o-linear-gradient(top, rgba(255,255,255,0.8) 0%,rgba(255,255,255,0.2) 100%); /* Opera 11.10+ */
    background: -ms-linear-gradient(top, rgba(255,255,255,0.8) 0%,rgba(255,255,255,0.2) 100%); /* IE10+ */
    background: linear-gradient(top, rgba(255,255,255,0.8) 0%,rgba(255,255,255,0.2) 100%); /* W3C */
    -moz-transition: background 0.2s linear;
    -webkit-transition:  background 0.2s linear;
    -o-transition:  background 0.2s linear;
    -ms-transition:  background 0.2s linear;
    transition:  background 0.2s linear;
}

.gb:hover::after,
.gb:focus::after {
    background: -moz-linear-gradient(top, rgba(255,255,255,0.75) 0%, rgba(255,255,255,0.2) 100%); /* FF3.6+ */
    background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,rgba(255,255,255,0.75)), color-stop(100%,rgba(255,255,255,0.2))); /* Chrome,Safari4+ */
    background: -webkit-linear-gradient(top, rgba(255,255,255,0.75) 0%,rgba(255,255,255,0.2) 100%); /* Chrome10+,Safari5.1+ */
    background: -o-linear-gradient(top, rgba(255,255,255,0.75) 0%,rgba(255,255,255,0.2) 100%); /* Opera 11.10+ */
    background: -ms-linear-gradient(top, rgba(255,255,255,0.75) 0%,rgba(255,255,255,0.2) 100%); /* IE10+ */
    background: linear-gradient(top, rgba(255,255,255,0.75) 0%,rgba(255,255,255,0.2) 100%); /* W3C */
}

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