网格CSS导航栏样式问题

Question

我想让我的导航栏下拉菜单使用CSS Grid在3列的“关于”下显示内容（如下图所示）。我希望“ nav-first-col”中的内容在第一栏中，“ nav-second-col”中的内容在第二栏中，“ nav-third-col”中的内容在第三栏中柱。但是，无论我如何尝试，“关于”下的内容似乎都全部显示在1列中。

package org.xtext.entries.ui.quickfix;

import org.eclipse.xtext.ui.editor.quickfix.DefaultQuickfixProvider;
import org.eclipse.xtext.ui.editor.quickfix.Fix;
import org.xtext.entries.validation.EntriesValidator;
import org.eclipse.xtext.validation.Issue;
import org.eclipse.xtext.ui.editor.quickfix.IssueResolutionAcceptor;
import org.xtext.entries.entries.Entry;
import org.xtext.entries.Helper;
import org.eclipse.xtext.ui.editor.model.edit.IModificationContext;
import org.eclipse.xtext.ui.editor.model.edit.ISemanticModification;
import org.eclipse.emf.ecore.EObject;
import org.xtext.entries.entries.Entry;
import org.xtext.people.people.Person;

public class EntriesQuickfixProvider extends DefaultQuickfixProvider {



@Fix(EntriesValidator.BAN)
    public void tryOverride(final Issue issue, IssueResolutionAcceptor acceptor) {
        acceptor.accept(issue,
            "Try to override", 
            "Override",
            "override.gif", 
            new ISemanticModification() {
                public void apply(EObject element, IModificationContext context) {
                    Entry entry = (Entry) element;
                    System.out.println(entry.getPerson());
                }
            }
        );
}

}

.nav-bar-main-menu .dropdown:nth-child(2) ul li{
  display: grid;
  grid-template-columns: 150px 150px 150px;
  grid-auto-rows: auto;
  grid-gap: 1em;
}

.nav-first-col{
  grid-column: 1 ;
}

.nav-second-col{
  grid-column: 2 ;
}

.nav-third-col{
  grid-column: 3 ;
}

Answer 1

.nav-bar-main-menu .dropdown:nth-child(2) ul li{
  display: grid;
  grid-template-columns: 150px 150px 150px;
  grid-auto-rows: auto;
  grid-gap: 1em;
}

.nav-first-col{
    grid-column: 1 ;
    display: inline-grid;
}

.nav-second-col{
    grid-column: 2 ;
    display: inline-grid;
}

.nav-third-col{
    grid-column: 3 ;
    display: inline-grid;
}

    <div class="nav-bar-main-menu">
        <div class="dropdown">
            <button class="dropbtn"><a href="#">HOME</a></button>
        </div>
        <div class="dropdown">
            <button class="dropbtn">PROJECT</button>
              <div class="dropdown-content">
                <a href="#">Link 1</a>
                <a href="#">Link 2</a>
                <a href="#">Link 3</a>
            </div>
        </div>
        <div class="dropdown">
            <button class="dropbtn">HUMAN-CENTERED DESIGN</button>
              <div class="dropdown-content">
                <a href="#">Link 1</a>
                <a href="#">Link 2</a>
                <a href="#">Link 3</a>
              </div>
        </div>
        <div class="dropdown">
            <button class="dropbtn">OUTREACH</button>
              <div class="dropdown-content">
                <a href="#">Link 1</a>
                <a href="#">Link 2</a>
                <a href="#">Link 3</a>
              </div>
        </div>
        <div class="dropdown">
            <button class="dropbtn">ABOUT</button>
              <div class="dropdown-content">
                 <ul>
                    <div class="nav-first-col">
                      <li><a href="#">WET LAB</a>
                        <ul>
                          <li><a href="http://2017.igem.org/Team:Cornell/Proof">HYDROSENSE</a></li>
                          <li><a href="http://2017.igem.org/Team:Cornell/Parts">PARTS</a></li>
                          <li><a href="http://2017.igem.org/Team:Cornell/Protocol">PROTOCOLS</a></li>
                        </ul>
                      </li>
                      <li><a href="#">PRODUCT DEVELOPMENT</a>
                        <ul>
                          <li><a href="http://2017.igem.org/Team:Cornell/productdevoverview">OVERVIEW</a></li>
                          <li><a href="http://2017.igem.org/Team:Cornell/Hardware">OXYPONICS SYSTEM</a></li>
                          <li><a href="http://2017.igem.org/Team:Cornell/Software">DASHBOARD</a></li>
                          <li><a href="http://2017.igem.org/Team:Cornell/Design">DESIGN PROCESS</a></li>
                        </ul>
                      </li>
                    </div>
                    <div class = "nav-second-col">
                      <li><a href="#">MATHEMATICAL MODELING</a>
                        <ul>
                          <li><a href="http://2017.igem.org/Team:Cornell/Model">MODELING</a></li>
                          <li><a href="http://2017.igem.org/Team:Cornell/Animation">ANIMATION</a></li>
                        </ul>
                      </li>
                    </div>
                    <div class = "nav-third-col">
                      <li><a href="#">DOCUMENTATION</a>
                        <ul>
                          <li><a href="http://2017.igem.org/Team:Cornell/Notebook">NOTEBOOK</a></li>
                          <li><a href="http://2017.igem.org/Team:Cornell/Safety">SAFETY</a></li>
                        </ul>
                     </div>
                    </li>
                 </ul>
              </div>
        </div>
        <div class="dropdown">
            <button class="dropbtn">TEAM</button>
              <div class="dropdown-content">
                <a href="#">Link 1</a>
                <a href="#">Link 2</a>
                <a href="#">Link 3</a>
              </div>
        </div>
    </div>

    </div>

对网格系统不是很熟悉，但这似乎行得通吗？