alevel_project/public/css/image-upload.css

#upload-files .wrapper {
    display: -webkit-box;
    display: -ms-flexbox;
    display: flex;
    -webkit-box-orient: horizontal;
    -webkit-box-direction: normal;
    -ms-flex-direction: row;
    flex-direction: row;
    -ms-flex-wrap: wrap;
    flex-wrap: wrap;
    -webkit-box-align: center;
    -ms-flex-align: center;
    align-items: center;
    -webkit-box-pack: center;
    -ms-flex-pack: center;
    justify-content: center;
}

#upload-files .box {
    position: relative;
    display: block;
    min-width: 160px;
    height: 180px;
    margin: 10px;
    background-color: white;
    border-radius: 5px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.12), 0 1px 2px rgba(0, 0, 0, 0.24);
    -webkit-transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
    transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
    overflow: hidden;
}

#upload-files .wrapper .box:first-child {
    background-color: #e6ffe6;
}

#upload-files .upload-options {
    position: relative;
    height: 40px;
    background-color: cadetblue;
    cursor: pointer;
    overflow: hidden;
    text-align: center;
    -webkit-transition: background-color ease-in-out 150ms;
    transition: background-color ease-in-out 150ms;
}

#upload-files .upload-options:hover {
    background-color: #7fb1b3;
}

#upload-files .upload-options label {
    padding-top: 3px;
    width: 100%;
    height: 100%;
    cursor: pointer;
    overflow: hidden;
}

#upload-files .upload-options span {
    position: relative;
    margin: auto;
    color: #e6ffe6;
    font-size: 2.1em;
}

#upload-files .upload-options label span:hover {
    color: white;
}

#upload-files .upload-options input {
    width: 0.1px;
    height: 0.1px;
    opacity: 0;
    overflow: hidden;
    position: absolute;
    z-index: -1;
}

#upload-files .js--image-preview {
    height: 140px;
    width: 100%;
    position: relative;
    overflow: hidden;
    background-image: url("");
    background-color: transparent;
    /*background-color: white;*/
    background-position: center center;
    background-repeat: no-repeat;
    background-size: cover;
}

#upload-files .js--image-preview span {
    font-size: 5.5em;
    color: #7fb1b3; /*##bfbfbf;*/
    margin-top: 15%;
    margin-left: auto;
    z-index: 0;
}

#upload-files .js--image-preview.js--no-default::after {
    display: none;
}

@-webkit-keyframes ripple {
    100% {
        opacity: 0;
        -webkit-transform: scale(2.5);
        transform: scale(2.5);
    }
}

@keyframes ripple {
    100% {
        opacity: 0;
        -webkit-transform: scale(2.5);
        transform: scale(2.5);
    }
}

/* Required field START */

#upload-files .required-field-block {
    position: relative;
}

#upload-files .required-field-block .required-icon {
    display: inline-block;
    vertical-align: middle;
    background-color: rgba(240, 240, 240, 0.9); /*#E8E8E8;*/
    border-color: rgba(240, 240, 240, 0.9); /*#E8E8E8;*/
    padding: 0.5em 0.8em;
    text-transform: uppercase;
    font-weight: normal;
    border-radius: 0.325em;
    -webkit-box-sizing: border-box;
    -moz-box-sizing: border-box;
    -ms-box-sizing: border-box;
    box-sizing: border-box;
    -webkit-transition: background 0.1s linear;
    -moz-transition: background 0.1s linear;
    transition: background 0.1s linear;
}

#upload-files.required-field-block .required-icon {
    background-color: transparent;
    position: absolute;
    top: -0.1em;
    right: -0.1em;
    z-index: 10;
    margin: 0em;
    width: 30px;
    height: 30px;
    padding: 0em;
    text-align: center;
    -webkit-transition: color 0.2s ease;
    -moz-transition: color 0.2s ease;
    transition: color 0.2s ease;
}

.required-field-block .required-icon:after {
    position: absolute;
    content: "";
    right: 1px;
    top: 1px;
    z-index: -1;
    width: 0em;
    height: 0em;
    border-top: 0em solid transparent;
    border-right: 38px solid transparent;
    border-bottom: 38px solid transparent;
    border-left: 0em solid transparent;
    border-right-color: inherit;
    -webkit-transition: border-color 0.2s ease;
    -moz-transition: border-color 0.2s ease;
    transition: border-color 0.2s ease;
}

.required-field-block .required-icon .text {
    color: #B80000;
    font-size: 26px;
    margin: -3px 0 0 12px;
}

/* Required field END */