File: static/css/speech-input.css

.si-wrapper {
    display: inline-block;
    position: relative;
}

.si-wrapper input {
    margin: 0;
}

.si-wrapper button {
    position: absolute;
    top: 0;
    right: 0;
    height: 18px;
    width: 18px;
    margin: 0;
    border: 0;
    padding: 0;
    background: none;
    font: 0/0 a;
}

.si-mic,
.si-mic:after,
.si-holder,
.si-holder:before,
.si-holder:after {
    position: absolute;
    background: #333;
}

/* Microphone icon */
.si-mic {
    display: block;
    height: 25%; /* 8px / 32px */
    top: 9.375%; /* 3px / 32px */
    left: 37.5%; /* 12px / 32px */
    right: 37.5%; /* 12px / 32px */
    -webkit-border-radius: 99px 99px 0 0;
    -moz-border-radius: 99px 99px 0 0;
    border-radius: 99px 99px 0 0;
}

.si-mic:before,
.si-mic:after,
.si-holder {
    -webkit-border-radius: 0 0 99px 99px;
    -moz-border-radius: 0 0 99px 99px;
    border-radius: 0 0 99px 99px;
}

.si-mic:before {
    position: absolute;
    z-index: 1;
    content: '';
    width: 150%; /* 12px / 8px */
    height: 137.5%; /* 11px / 8px */
    top: 100%; /* 8px / 8px */
    left: -25%; /* -2px / 8px */
    background: #fff;
}

.si-mic:after {
    z-index: 1;
    content: '';
    width: 100%; /* 10px / 10px */
    height: 100%; /* 10px / 10px */
    top: 110%; /* 11px / 10px */
    left: 0;
}

.si-holder {
    display: block;
    height: 40.625%; /* 13px / 32px */
    width: 50%; /* 16px / 32px */
    left: 25%; /* 8px / 32px */
    top: 37.5%; /* 12px / 32px */
}

.si-holder:after {
    content: '';
    width: 66.666%; /* 8px / 16px */
    height: 18.182%; /* 2px / 13px */
    bottom: -30.769%; /* -4px / 13px */
    left: 16.667%; /* 2px / 16px */
}

.si-holder:before {
    content: '';
    width: 33.333%; /* 4px / 16px */
    height: 27.273%; /* 3px / 13px */
    top: 92.308%; /* 12px / 13px */
    left: 33.333%; /* 4px / 16px */
}