def replace_chunk(text, start_str, end_str, new_content):
    start = text.find(start_str)
    end = text.find(end_str, start)
    if start != -1 and end != -1:
        end += len(end_str)
        return text[:start] + new_content + text[end:]
    return text

with open('app/modules/sag/templates/detail.html', 'r') as f:
    text = f.read()

# Test finding CSS
start_css = ".time-v1-track {"
end_css = "        .time-v1-metric {\n            font-size: 0.8rem;\n            margin-top: 0.18rem;\n        }"
if start_css in text and end_css in text:
    print("Found CSS block")

# Test finding JS
start_js = "        function renderTimeV1Timeline(entries) {"
end_js = "                    </div>\n                `;\n            }).join('');\n        }"
if start_js in text and end_js in text:
    print("Found JS block")