NavBar.svelte

<nav>
  <svg viewBox="0 0 2 3" aria-hidden="true">
    <path d="M0,0, L1, 2 C1.5, 3 1.5, 3, 2, 3, L2, 0Z" />
  </svg>
  <ul>
    <li aria-current={$page.url.pathname === '/' ? 'page' : undefined}>
    <a href="/">Home</a>
    </li>
    <li aria-current={$page.url.pathname === '/pool' ? 'page' : undefined}>
    <a href="/pool">Pool Play</a>
    </li>
    <li aria-current={$page.url.pathname === '/bracket' ? 'page' : undefined}>
    <a href="/bracket">Bracket Play</a>
    </li>
    <li aria-current={$page.url.pathname === '/admin' ? 'page' : undefined}>
    <a href="/admin">Admin Stuff</a>
    </li>
  </ul>
  <svg viewBox="0 0 2 3" aria-hidden="true">
    <path d="M0,0 L0,3 C0.5,3 0.5,3 1,2 L2,0 Z" />
  </svg>
</nav>

<style>
  nav {
    display: flex;
    justify-content: center;
    --background: var(--color-theme-3);
  }

  svg {
    width: 2em;
    height: 3em;
    display: block;
  }

  path {
    fill: var(--color-theme-3);
  }

  ul {
    position: relative;
    padding: 0;
    margin: 0;
    height: 3em;
    display: flex;
    justify-content: center;
    align-items: center;
    list-style: none;
    background: var(--background);
    background-size: contain;
  }

  li {
    position: relative;
    height: 100%;
  }

  li[aria-current='page']::before {
    --size: 10px;
    content: '';
    width: 0;
    height: 0;
    position: absolute;
    top: 0;
    left: calc(50% - var(--size));
    border: var(--size) solid transparent;
    border-top: var(--size) solid var(--color-theme-1);
  }

  nav a {
    display: flex;
    height: 100%;
    align-items: center;
    padding: 0 0.5rem;
    color: var(--color-text);
    font-weight: 700;
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    text-decoration: none;
    transition: color 0.2s linear;
  }

  a:hover {
    color: var(--color-theme-2);
  }
</style>