How do you you reduce the space between paragraph to paragraph

Question

I'm trying to make the space that separates the paragraphs smaller. I've tried changing the top and bottom margins in CSS but it doesn't make any major changes, I went all the way down to 00px but no change. I even took out the
's. Maybe I'm overlooking something but I can't seem to put my finger on it.

#content {
  font: normal 100% Arial, Helvetica, sans-serif;
  width: 680px;
  margin: 0 0 20px 10px;
  float: left;
}

.content_item {
  width: 680px;
  margin-top: .20px;
  margin-bottom: .20px;
  margin-left: auto;
  text-align: justify;
  text-justify: inter-word;
  line-height: 1.5;
}

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  <div class="content_item">
  
    <h1>Specific project goals are</h1>


    <ul>
      <li>To build the big data and cloud computing research capacity at Winston-Salem state university.</li>
      <li>To involve undergraduate students in cutting-edge research.</li>
      <li>To enhance educational experiences for CS and IT majors at WSSU.
      </li>
      <li>To expand the participation of underrepresented minority, specifically women, in STEM and support the nation’s efforts in building a robust STEM workforce.</li>
    </ul>
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    <h1>Current Fundings</h1>

    <ul>
      <li>NSF, “Improving Research and Education of Big Data and Cloud Computing at Winston-Salem State University”, <a href="https://www.nsf.gov/awardsearch/showAward?AWD_ID=1600864&HistoricalAwards=fal"><strong>Award Number: 1600864</strong>
    </a> $307,802, 2016 – 2019. </li>

      <li>NSF, “Collaborative Research: Excellence In Research: Computational Framework and Data Science for Identification”, <a href="https://www.nsf.gov/awardsearch/showAward?AWD_ID=1900087&HistoricalAwards=false),"><strong>Award Number: 1900087</strong>
    </a> $299,962, 2019-2022. </li>

      <li>NSF, “Targeted Infusion Project: “Integrating Data Science into the Urban Studies and Sustainability Program”, <a href="https://www.nsf.gov/awardsearch/showAward?AWD_ID=1912214&HistoricalAwards=false"><strong>Award Number: 1912214</strong>
    </a> $249,825.00, 2019-2022. </li>


    </ul>
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<div id="content">
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    <h1>Previous Fundings </h1>

    <ul>
      <li><b>UNC Research Cyberinfrastructure Colaboration Grant</b></li>
      Senior personnel: Dr. Debzani Deb, WSSU
      <li><b>WSSU RIP Award</b></li>
      “Utility-based Resource Provisioning of Big Data Applications on Cloud Environment”<br /> Amount: $9,690.00<br /> June, 2016 to November, 2017<br /> PI: Dr. Debzani Deb, WSSU

    </ul>

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