index.scss

body {
    margin: 0;
    padding: 0;
    overflow: hidden;
}

.about-section, .welcome-section {
    width: 80vw;
    display: -webkit-box;
    display: -ms-flexbox;
    display: flex;
    -webkit-box-orient: vertical;
    -webkit-box-direction: normal;
    -ms-flex-flow: column nowrap;
    flex-flow: column nowrap;
    -webkit-box-align: stretch;
    -ms-flex-align: stretch;
    align-items: stretch;

    .about-modal-footer {
        display: flex;
        flex: 1;
        justify-content: space-around;
        width: 100%;
    }
}

.welcome-section {
    animation: anim 0.4s linear;
    @keyframes anim {
        0% {
            opacity: 0 !important;
            -webkit-transform: scale(0.1);
            -moz-transform: scale(0.1);
            -ms-transform: scale(0.1);
            transform: scale(0.1);
        }

        70% {
            -webkit-transform: scale(1.1);
            -moz-transform: scale(1.1);
            -ms-transform: scale(1.1);
            transform: scale(1.1);
        }

        100% {
            opacity: 1 !important;
            -webkit-transform: scale(1);
            -moz-transform: scale(1);
            -ms-transform: scale(1);
            transform: scale(1);
        }
    }
}

.about-header {
    -webkit-box-flex: 1;
    -ms-flex: 1 1 auto;
    flex: 1 1 auto;
    background: #0078d4;
    color: #fff;
    display: -webkit-box;
    display: -ms-flexbox;
    display: flex;
    -webkit-box-align: center;
    -ms-flex-align: center;
    align-items: center;
    font-size: 1.5em;
    font-weight: 100;
    font-weight: 600;
    padding: 0 28px;
    min-height: 40px;
}

.modal-body {
    -webkit-box-flex: 4;
    -ms-flex: 4 4 auto;
    flex: 4 4 auto;
    padding: 5px 28px;
    overflow-y: auto;
}

.close-modal-icon {
    position: absolute;
    right: 2%;
    cursor: pointer;
}

.ms-Panel-content {
    padding: 0;
}

*[data-toolbar-option=bg-selector],
*[data-toolbar-option=effect-selector],
*[data-toolbar-option=particles-config],
*[data-toolbar-option=paint-config] {
    padding: 1em;
    width: 100%;
}

*[data-toolbar-option=reset-canvas] {
    padding: 1em;
    position: absolute;
    top: 0;
    left: 0;
    width: 81.2%;
}

div[data-toolbar-item=bg-color-display] {
    width: 88%;
    height: 2em;
    margin: auto;
    margin-top: 1em;
    display: flex;
    flex-direction: row;
    align-items: center;
    .palette {
        flex: 1;
        margin-right: 0.2em;
        height: 100%;
        border: 1px solid #c8c6c4;
    }
}

#particles-js {
    height: 100vh;
    width: 100vw;
    position: absolute;
    top: 0;
    z-index: -1;
}

#effects-dropdown,
#particles-type-dropdown,
.density-slider {
    width: 88%;
    margin: auto;
}

.collapseTwoContent,
.particles-config-collapse,
.paint-config-collapse {
    padding: 1em;
}

.new-file-modal {
    min-width: fit-content;
    min-width: -moz-fit-content;
    min-width: -webkit-fit-content;
}

.particles-color-picker {
    .ms-ColorPicker-panel {
        padding-left: 0;
        padding-right: 0;
    }
    &+*[data-toolbar-item=bg-color-display] {
        width: 100%;
    }
}

.new-file-modal .new-file-modal-footer > div {
    display: flex;
    span {
        @media only screen and (max-width: 560px) {
            margin-bottom: 5px;
            width: 100%;
        }

        button {
            width: 100%;
        }
    }
    @media only screen and (max-width: 560px) {
        flex-direction: column;
        align-items: center;
    }
}