:root   {
    --white-color: #fff;
    --black-color: #000;
    --text-color: #333;
    --primary-color: rgb(169, 223, 240);
}
*   {
    box-sizing: inherit;
}
html    {
    font-size: 62.5%;
    line-height: 1.6 rem;
    font-family: 'Roboto', sans-serif;
    box-sizing: border-box;
}

.box{
    width: 1855px;
    max-width: 100%;
    margin: 0 auto;
}
.grid__full-width   {
    width: 100%;
}

.grid__row  {
    display: flex;
    flex-wrap: wrap;
}

/* Animation */
@keyframes  fadeIn  {
    from    {
        opacity: 0;
    }
    to      {
        opacity: 1;
    }
}
@keyframes transform {
    from    {
        opacity: 0;
        transform: scale(0);
    }
    to  {
        opacity: 1;
        transform: scale(1);
    }
}
@keyframes growth {
    from    {
        transform: scale(var(--growth-form));
    }
    to {
        transform: scale(var(--growth-to));
    }
    
}
/*modal*/
.modal  {
    position: fixed;
    top:0;
    right: 0;
    bottom: 0;
    left: 0;
    display: flex;
    animation: fadeIn linear 0.1s;
}
.modal__overlay {
    position: absolute;
    width: 100%;
    height: 100%;
    background-color: rgba(0,0,0,0.4);
    z-index: 1;
}
.modal__body    {
    --growth-from: 0.7;
    --growth-to: 1;
    background-color: var(--white-color);
    margin: auto;
    z-index: 2;
    border-radius: 5px;
    animation: growth linear 0.1s;
}
/* button-style */
.btn    {
    min-width: 142px;
    min-height: 36px;
    text-decoration: none;
    border: none;
    border-radius: 3px;
    font-size: 1.4rem;
    text-align: center;
    cursor: pointer;
}
.btn.btn-primary    {
    color: var(--black-color);
    background-color: var(--primary-color);
    filter: brightness(110%);
}
h1, h2, h3, h4, h5, h6 {
    margin-top: 0.7em;
    margin-bottom: 0.3em;
}
h1{
    font-size: 4rem;
}
h2{
    text-decoration: underline;
    font-size: 2rem;
}
.section_schematic  {
    width: 50%;
    border-radius: 20px;
}
#myDIV, #myDIV1,#myDIV2,#myDIV3,#myDIV4,#myDIV5,#myDIV6,#myDIV7,#myDIV8,#myDIV9,#myDIV10 {
    display: none;
    box-sizing: border-box;
    margin-top: 20px;
}
.section_name   {
    color: var(--white-color);
    pointer-events: painted;
}
.section_name:hover{
    color: var(--primary-color);
}