header {
    border: black 3px solid;
    border-radius: 20px;
    background-color: #e0e0e0;
    margin: 0;
    padding: 0;
    padding-bottom: 20px;
}

header button {
    border: 3px black solid;
    border-radius: 8px;
    transition: background-color 0.4s ease;
    padding: 15px;
    margin: 0px 25px;
    font-size: 20px;
}

header button:hover {
    background-color: black;
}

#Biology_Btn {
    background-color: rgb(137, 247, 137);
    border-color: rgb(11, 84, 30);
}

#Biology_Btn:hover {
    background-color: rgb(30, 111, 41);
}

#Chemistry_Btn {
    background-color: rgb(241, 199, 127);
    border-color: rgb(82, 58, 10);
}

#Chemistry_Btn:hover {
    background-color: rgb(161, 140, 63);
}

#Physics_Btn {
    background-color: rgb(239, 165, 122);
    border-color: rgb(100, 35, 11);
}

#Physics_Btn:hover {
    background-color: rgb(168, 84, 46);
}

.background-container {
    position: relative;
    width: 100%;
    height: 1080px; /* Or whatever height you need */
    overflow: hidden;
}
.background-image {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-size: cover;
    background-position: center;
    /* Animate the filter property */
    transition: opacity 0.5s ease-in-out; 
}
#first-image {
    background-image: url('Backgrounds/Default.png');
    opacity: 1;
}
#second-image {
    background-image: url('Backgrounds/Biology.png');
    opacity: 0
}

.content {
    position: relative;
    z-index: 1; /* Ensures content is above the background layers */
    /* Add styling for your content to be readable */
}

body {
    margin: 0;
    font-family: Arial, sans-serif;
    background: #f4f4f4;
    text-align: center;
    transition: opacity 1s ease;
    background-size: cover;
    height: 150%;
}

main{
    margin: 50px;
}

.notice{
   border-top: 1px black solid;
   text-align: left;
}
.notice h3{
   color: rgb(47, 47, 47);
}
.notice p{
    font-size: 20px;
    font-weight:normal;
    color: black;
}

.container {
    background: white;
    border: 10px rgb(163, 163, 163) solid;
    padding: 30px;
    max-width: 600px;
    margin: auto;
    border-radius: 30px;
    transition: height 1s ease;
}

#quiz{
    margin-top: 125px;
    padding: 70px;
}

button {
    padding: 10px 20px;
    margin-top: 15px;
    cursor: pointer;
}

textarea {
    width: 80%;
    padding: 10px;
    margin-top: 10px;
    resize: vertical;
    /* user can drag to resize */
    font-family: Arial, sans-serif;
}

.correct {
    background-color: #c8f7c5;
    padding: 2px 4px;
    border-radius: 4px;
    font-weight: bold;
}

.missed {
    background-color: #f7c5c5;
    padding: 2px 4px;
    border-radius: 4px;
    font-weight: bold;
}

#answerSection {
    overflow: hidden;
    max-height: 0;
    opacity: 0;
    transition: max-height 0.4s ease, opacity 0.3s ease;
}

#answerSection.show {
    max-height: 500px; /* large enough for your longest answer */
    opacity: 1;
}