body {
    font-family: 'Arial', sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f9f9f9;
    color: #333;
}

header {
    background-color: #007BFF;
    color: white;
    padding: 20px;
    text-align: center;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    border-bottom: 3px solid #0056b3; /* More contrast */
}

header h1 {
    font-size: 28px;
    margin: 0;
    letter-spacing: 2px;
    text-transform: uppercase;
}

main {
    padding: 40px 20px;
    background-color: #fff;
    box-shadow: 0 2px 15px rgba(0, 0, 0, 0.1);
    border-radius: 10px;
    margin: 20px auto;
    max-width: 1000px;
}

h2 {
    color: #333;
    margin-top: 20px;
    font-size: 26px;
    text-transform: uppercase;
    font-weight: bold;
    border-bottom: 2px solid #007BFF;
    padding-bottom: 10px;
}

ul, ol {
    text-align: left;
    margin: 20px auto;
    max-width: 700px;
    padding-left: 20px;
    line-height: 1.8;
    font-size: 18px;
}

ul li, ol li {
    margin-bottom: 10px;
}

iframe {
    display: block;
    margin: 20px auto;
    width: 80%;
    max-width: 700px;
    height: 420px;
    border: 2px solid #007BFF;
    border-radius: 8px;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
}

iframe:hover {
    transform: scale(1.05);
}

.experiment-image {
    width: 100%;
    max-width: 650px;
    height: auto;
    display: block;
    margin: 20px auto;
    border: 3px solid #ddd;
    border-radius: 10px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
}

.experiment-image:hover {
    transform: scale(1.05);
}

.experiment-image:active {
    transform: scale(1);
}

/* Section for each experiment (container for image, text, and video) */
.experiment-section {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    margin-bottom: 30px;
}

.experiment-section .text-content {
    flex: 1;
    padding: 20px;
    background-color: #f1f1f1;
    border-radius: 10px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    margin-right: 20px;
    max-width: 45%;
}

.experiment-section .text-content h2 {
    font-size: 24px;
    color: #007BFF;
}

.experiment-section .text-content p {
    font-size: 18px;
}

.experiment-section .text-content ul, .experiment-section .text-content ol {
    padding-left: 30px;
    font-size: 16px;
}

.experiment-section .video-frame {
    flex: 1;
    max-width: 45%;
    background-color: #f1f1f1;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    display: flex;
    justify-content: center;
}

.experiment-section .video-frame iframe {
    max-width: 100%;
    height: 420px;
    border-radius: 10px;
}

/* Experiment Image Gallery */
.experiment-gallery {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin-top: 30px;
}

.experiment-gallery .experiment-image {
    transition: transform 0.3s ease;
    cursor: pointer;
}

.experiment-gallery .experiment-image:hover {
    transform: scale(1.1);
}

.experiment-gallery .experiment-image:active {
    transform: scale(1);
}

/* Buttons (Optional, for future interactivity) */
button {
    background-color: #007BFF;
    color: white;
    padding: 12px 25px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 18px;
    transition: background-color 0.3s ease;
}

button:hover {
    background-color: #0056b3;
}

/* Add some space at the bottom of the page */
footer {
    background-color: #007BFF;
    color: white;
    text-align: center;
    padding: 20px 0;
    font-size: 16px;
    position: fixed;
    bottom: 0;
    width: 100%;
    box-shadow: 0 -2px 5px rgba(0, 0, 0, 0.1);
}

/* Add these media queries */
@media (max-width: 768px) {
    main {
        padding: 20px 15px;
        margin: 10px;
    }

    .experiment-section {
        flex-direction: column;
    }

    .experiment-section .text-content,
    .experiment-section .video-frame {
        max-width: 100%;
    }

    .experiment-section .video-frame iframe {
        height: 240px;
    }

    ul, ol {
        padding-left: 15px;
        font-size: 16px;
    }

    header h1 {
        font-size: 24px;
    }

    h2 {
        font-size: 22px;
    }

    .experiment-image {
        max-width: 100%;
    }

    footer {
        position: static;
        padding: 15px 0;
    }
}
.progress-container {
    margin: 20px 0;
    padding: 20px;
    background-color: #f5f5f5;
    border-radius: 8px;
}

.progress-bar {
    width: 100%;
    height: 20px;
    background-color: #ddd;
    border-radius: 10px;
    overflow: hidden;
}

.progress {
    width: 0%;
    height: 100%;
    background-color: #4CAF50;
    transition: width 0.5s ease-in-out;
}

.quiz-section {
    margin: 30px 0;
    padding: 20px;
    background-color: #f9f9f9;
    border-radius: 8px;
}

.quiz {
    margin-bottom: 30px;
}

.options {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin: 15px 0;
}

.options label {
    display: block;
    padding: 10px;
    background-color: #fff;
    border: 1px solid #ddd;
    border-radius: 5px;
    cursor: pointer;
}

.options label:hover {
    background-color: #f0f0f0;
}

#submitQuiz {
    padding: 10px 20px;
    background-color: #4CAF50;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
}

#submitQuiz:hover {
    background-color: #45a049;
}

#quizResult {
    margin-top: 20px;
    padding: 15px;
    border-radius: 5px;
}

.correct {
    background-color: #dff0d8;
    color: #3c763d;
}

.incorrect {
    background-color: #f2dede;
    color: #a94442;
}