Table Column Visibility Toggle Menu — Real Dynamic Show/Hide Columns

<div class="demo">
  <div class="col-toolbar">
    <div class="col-menu-wrap">
      <button class="col-menu-btn" id="colMenuBtn" aria-haspopup="true" aria-expanded="false">
        <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.2" stroke-linecap="round"><path d="M4 6h16M4 12h16M4 18h16"/></svg>
        Columns
        <span class="col-count" id="colCount"></span>
      </button>
      <div class="col-menu" id="colMenu" role="menu">
        <label class="col-item"><input type="checkbox" data-col="email" checked /><span>Email</span></label>
        <label class="col-item"><input type="checkbox" data-col="role" checked /><span>Role</span></label>
        <label class="col-item"><input type="checkbox" data-col="status" checked /><span>Status</span></label>
        <label class="col-item"><input type="checkbox" data-col="lastActive" checked /><span>Last active</span></label>
        <label class="col-item"><input type="checkbox" data-col="joined" /><span>Joined date</span></label>
      </div>
    </div>
  </div>

  <table class="col-table" id="colTable">
    <thead>
      <tr>
        <th>Name</th>
        <th data-col="email">Email</th>
        <th data-col="role">Role</th>
        <th data-col="status">Status</th>
        <th data-col="lastActive">Last active</th>
        <th data-col="joined">Joined date</th>
      </tr>
    </thead>
    <tbody>
      <tr>
        <td>Maya Chen</td>
        <td data-col="email">[email protected]</td>
        <td data-col="role">Admin</td>
        <td data-col="status"><span class="badge on">Active</span></td>
        <td data-col="lastActive">2 hours ago</td>
        <td data-col="joined">Jan 12, 2024</td>
      </tr>
      <tr>
        <td>Rahul Patel</td>
        <td data-col="email">[email protected]</td>
        <td data-col="role">Editor</td>
        <td data-col="status"><span class="badge on">Active</span></td>
        <td data-col="lastActive">1 day ago</td>
        <td data-col="joined">Mar 4, 2024</td>
      </tr>
      <tr>
        <td>Ines Fischer</td>
        <td data-col="email">[email protected]</td>
        <td data-col="role">Viewer</td>
        <td data-col="status"><span class="badge off">Inactive</span></td>
        <td data-col="lastActive">3 weeks ago</td>
        <td data-col="joined">Jun 20, 2024</td>
      </tr>
    </tbody>
  </table>
</div>

* { box-sizing: border-box; margin: 0; padding: 0; }
body { font-family: system-ui, sans-serif; background: #f8fafc; display: flex; align-items: center; justify-content: center; min-height: 100vh; padding: 24px; }
.demo { width: 580px; max-width: 100%; display: flex; flex-direction: column; gap: 10px; }

.col-toolbar { display: flex; justify-content: flex-end; }
.col-menu-wrap { position: relative; }
.col-menu-btn { display: flex; align-items: center; gap: 7px; background: #fff; border: 1.5px solid #e2e8f0; padding: 8px 13px; border-radius: 9px; font-size: 12.5px; font-weight: 700; color: #475569; cursor: pointer; font-family: inherit; }
.col-menu-btn:hover { background: #f8fafc; }
.col-count { background: #eef2ff; color: #4338ca; font-size: 10.5px; font-weight: 800; padding: 1px 7px; border-radius: 999px; }

.col-menu { position: absolute; top: calc(100% + 6px); right: 0; background: #fff; border: 1px solid #e2e8f0; border-radius: 12px; box-shadow: 0 12px 28px rgba(15,23,42,0.12); padding: 6px; min-width: 170px; display: none; flex-direction: column; z-index: 10; }
.col-menu.open { display: flex; }
.col-item { display: flex; align-items: center; gap: 9px; padding: 8px 10px; font-size: 12.5px; font-weight: 600; color: #334155; border-radius: 7px; cursor: pointer; }
.col-item:hover { background: #f8fafc; }
.col-item input { width: 15px; height: 15px; accent-color: #6366f1; cursor: pointer; }

.col-table { width: 100%; border-collapse: collapse; background: #fff; border: 1px solid #e2e8f0; border-radius: 14px; overflow: hidden; font-size: 13px; }
.col-table th { text-align: left; padding: 11px 14px; background: #f8fafc; color: #64748b; font-size: 10.5px; font-weight: 700; text-transform: uppercase; letter-spacing: 0.04em; border-bottom: 1px solid #e2e8f0; }
.col-table td { padding: 11px 14px; color: #1f2937; border-bottom: 1px solid #f1f5f9; }
.col-table tr:last-child td { border-bottom: none; }
.col-table [data-col].col-hidden { display: none; }

.badge { font-size: 10.5px; font-weight: 700; padding: 3px 9px; border-radius: 999px; }
.badge.on { background: #dcfce7; color: #15803d; }
.badge.off { background: #f1f5f9; color: #64748b; }

const menuBtn = document.getElementById('colMenuBtn');
const menu = document.getElementById('colMenu');
const colCount = document.getElementById('colCount');
const table = document.getElementById('colTable');
const checkboxes = Array.from(menu.querySelectorAll('input[data-col]'));

function applyVisibility() {
  checkboxes.forEach((cb) => {
    const col = cb.dataset.col;
    const hidden = !cb.checked;
    // Toggle every cell (header and body) belonging to this column across
    // every row — a single querySelectorAll scoped to the whole table.
    table.querySelectorAll(`[data-col="${col}"]`).forEach((cell) => {
      cell.classList.toggle('col-hidden', hidden);
    });
  });

  const visibleCount = checkboxes.filter((cb) => cb.checked).length;
  const totalCount = checkboxes.length;
  colCount.textContent = `${visibleCount + 1}/${totalCount + 1}`; // +1 accounts for the always-visible Name column
}

checkboxes.forEach((cb) => {
  cb.addEventListener('change', applyVisibility);
});

menuBtn.addEventListener('click', () => {
  const open = menu.classList.toggle('open');
  menuBtn.setAttribute('aria-expanded', String(open));
});

document.addEventListener('click', (e) => {
  if (!e.target.closest('.col-menu-wrap')) {
    menu.classList.remove('open');
    menuBtn.setAttribute('aria-expanded', 'false');
  }
});

applyVisibility();