* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    height: 800px;
}

nav {
    float: right;
    margin-top: 20px;
    margin-right: 20px;
    display: flex;
    position: sticky;
    top: 20px;
}

nav>* {
    margin-right: 5px;
}

nav>button {
    border: hidden;
    height: 25px;
    padding: 5px;
    background: orangered;
}

#categories {
    border: hidden;
    height: 25px;
    background: orangered;
    color: white;
    cursor: pointer;
}

button {
    cursor: pointer;
    color: white;
}

.switch {
    position: relative;
    display: inline-block;
    width: 50px;
}

.switch input {
    opacity: 0;
    width: 0;
    height: 0;
}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    bottom: 0;
    left: 0;
    right: 0;
    background-color: #ccc;
    transition: 4s;
    -webkit-transition: 4s;
}

.slider::before {
    position: absolute;
    content: "";
    height: 15px;
    width: 15px;
    left: 4px;
    bottom: 4px;
    background-color: white;
}

input:checked+.slider {
    background-color: #33373a;
}

input:focus+.slider {
    box-shadow: 0 0 1px rgba(9, 84, 146, 0.247);
}

input:checked+.slider::before {
    transform: translateX(26px);
}

.slider.round {
    border-radius: 34px;
}

.slider.slider.round::before {
    border-radius: 50%;
}

li {
    display: block;
    transition-duration: 0.5s;
    color: #ffffff;
    background: #ff4500;
    padding: 3px;
    position: relative;
    text-decoration: hidden;
}

#page-control {
    background: orangered;
    padding: 5px;
    width: 100px;
    display: flex;
    flex-flow: column nowrap;
    align-items: center;
    justify-content: space-between;
    position: fixed;
    bottom: 50px;
    right: 5px;
}

#page-control * {
    width: 100%;
}

#page-control :nth-child(1) {
    text-align: center;
    color: white;
}



#next {
    margin-left: 3px;

}

#install_banner {
    display: flex;
    flex-flow: column wrap;
    justify-content: center;
    align-items: center;
    margin-left: 20px;
    margin-top: 15px;
    padding: 10px;
    background: orangered;
    width: 290px;
}

#install_banner>* {
    margin-top: 5px;
    color: white;
}

#installBtn {
    width: 90px;
    height: 40px;
    border: hidden;
    border-radius: 2px;
    background: rgba(7, 92, 204, 0.979);
}

#container {
    display: flex;
    flex-flow: column nowrap;
    align-items: center;
    margin: 5px auto;
    width: 60vw;
    height: 100vh;
}

#container>* {
    padding: 10px;
    border: 1px rgba(0, 0, 0, 0.103) solid;
    border-radius: 2px;
}


#question {
    width: 100%;
    min-height: 10%;
    text-align: center;
    overflow-y: auto;
}

#img {
    width: 80%;
    margin-top: 5px;
}

#answers {
    width: 100%;
    display: flex;
    flex-wrap: column nowrap;
    justify-content: center;
    align-items: center;
    margin-top: 5px;

}

#answers {
    display: block;
}

form {
    display: flex;
    flex-flow: column nowrap;
    margin: auto;
    width: 80%;
}

form>* {
    margin-top: 15px;
}

form :nth-child(4) {
    align-self: center;
    border: hidden;
    padding: 10px;
    cursor: pointer;
    border-radius: 3px;
    color: white;
    background-color: rgba(0, 128, 0, 0.795);
}

.ans {
    cursor: pointer;
}

.about {
    background: linear-gradient(50deg, rgb(14, 103, 204), rgba(27, 29, 163, 0.801));
    width: 250px;
    color: white;
    position: fixed;
    top: 50%;
    left: 40%;
    transform: translate(-50,50);
    padding: 40px;
    border-radius: 6px;
    cursor: pointer;
    display: flex;
    flex-flow: column nowrap;
}

/* dark mode */
.c2{
    background-color: #33373a;
}
.c1{
    background-color: #222;
}
.c1 > * {
    color:white;
}

@media all and (display-mode: standalone) {
    #install_banner {
        visibility: hidden;

    }
}