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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f5f5;
    padding: 20px;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    background-color: white;
    padding: 40px;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

h1 {
    text-align: center;
    margin-bottom: 10px;
    color: #2c3e50;
}

.progress-bar-container {
    width: 100%;
    height: 8px;
    background-color: #e0e0e0;
    border-radius: 4px;
    margin-bottom: 10px;
    overflow: hidden;
}

.progress-bar {
    height: 100%;
    background-color: #3498db;
    transition: width 0.3s ease;
}

.progress {
    text-align: center;
    margin-bottom: 30px;
    color: #666;
    font-size: 14px;
}

.study-section {
    display: none;
}

.study-section.active {
    display: block;
    animation: fadeIn 0.3s ease-in;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.instruction-box {
    background-color: #e8f4f8;
    padding: 20px;
    border-radius: 6px;
    margin-bottom: 30px;
    border-left: 4px solid #3498db;
}

.instruction-box h2 {
    margin-bottom: 10px;
    color: #2980b9;
    font-size: 18px;
}

.instruction-box p {
    font-size: 16px;
}

.svg-container {
    text-align: center;
    margin-bottom: 30px;
    padding: 20px;
    background-color: #fafafa;
    border-radius: 6px;
}

.svg-container h3 {
    margin-bottom: 15px;
    color: #2c3e50;
}

.video-comparison {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    margin-bottom: 30px;
}

.video-box {
    text-align: center;
}

.video-box h3 {
    margin-bottom: 15px;
    color: #2c3e50;
}

video {
    width: 100%;
    max-width: 500px;
    border-radius: 6px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    background-color: #000;
}

.response-section {
    margin-top: 30px;
    padding: 20px;
    background-color: #f9f9f9;
    border-radius: 6px;
}

.response-section h3 {
    margin-bottom: 15px;
    color: #2c3e50;
}

.radio-group {
    margin-bottom: 20px;
}

.radio-option {
    display: block;
    padding: 12px;
    margin-bottom: 10px;
    background-color: white;
    border: 2px solid #ddd;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.2s;
}

.radio-option:hover {
    border-color: #3498db;
    background-color: #f0f8ff;
}

.radio-option input[type="radio"] {
    margin-right: 10px;
}

.radio-option.selected {
    border-color: #3498db;
    background-color: #e8f4f8;
}

textarea {
    width: 100%;
    padding: 12px;
    border: 2px solid #ddd;
    border-radius: 6px;
    font-family: inherit;
    font-size: 14px;
    resize: vertical;
    min-height: 80px;
}

.button-group {
    display: flex;
    justify-content: space-between;
    margin-top: 30px;
}

button {
    padding: 12px 30px;
    font-size: 16px;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.2s;
    font-weight: 500;
}

.btn-primary {
    background-color: #3498db;
    color: white;
}

.btn-primary:hover:not(:disabled) {
    background-color: #2980b9;
}

.btn-secondary {
    background-color: #95a5a6;
    color: white;
}

.btn-secondary:hover {
    background-color: #7f8c8d;
}

button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.intro-section,
.thank-you-section,
.submitting-section {
    text-align: center;
}

.intro-section h2,
.thank-you-section h2,
.submitting-section h2 {
    margin-bottom: 20px;
    color: #2c3e50;
}

.intro-section p,
.thank-you-section p,
.submitting-section p {
    margin-bottom: 15px;
    line-height: 1.8;
}

.consent-box {
    background-color: #fff3cd;
    padding: 20px;
    border-radius: 6px;
    margin: 20px 0;
    border-left: 4px solid #ffc107;
    text-align: left;
}

.info-box {
    background-color: #e8f5e9;
    padding: 15px;
    border-radius: 6px;
    margin: 20px 0;
    border-left: 4px solid #4caf50;
}

.success-box {
    background-color: #e8f5e9;
    padding: 20px;
    border-radius: 6px;
    margin: 20px 0;
    border-left: 4px solid #4caf50;
}

.error-box {
    background-color: #ffebee;
    padding: 20px;
    border-radius: 6px;
    margin: 20px 0;
    border-left: 4px solid #f44336;
}

.spinner {
    border: 4px solid #f3f3f3;
    border-top: 4px solid #3498db;
    border-radius: 50%;
    width: 50px;
    height: 50px;
    animation: spin 1s linear infinite;
    margin: 20px auto;
}

@keyframes spin {
    0% {
        transform: rotate(0deg);
    }

    100% {
        transform: rotate(360deg);
    }
}

.gist-link {
    word-break: break-all;
    background-color: #f5f5f5;
    padding: 10px;
    border-radius: 4px;
    margin: 10px 0;
    font-family: monospace;
}

@media (max-width: 768px) {
    .video-comparison {
        grid-template-columns: 1fr;
    }

    .container {
        padding: 20px;
    }
}