UI Components Medium

Allergy & Diet Filter

Multi-select allergen filter with avoid/prefer chips, live count of safe dishes, and an inline result list that explains why each dish was hidden.

Open in Lab

html css vanilla-js

Targets: JS HTML

Code

:root {
  --cream: #f5f0e8;
  --cream-2: #ece4d4;
  --bone: #faf7f1;
  --terracotta: #c1714a;
  --terracotta-d: #a05a38;
  --forest: #2d4a3e;
  --forest-d: #1e3329;
  --gold: #c9a84c;
  --gold-light: #e6c97a;
  --ink: #2c1a0e;
  --ink-2: #4a3828;
  --warm-gray: #7a6a58;
  --success: #4f7a3a;
  --danger: #b3432a;
  --warning: #d99020;
  --font-display: "Playfair Display", Georgia, serif;
  --font-body: "Inter", system-ui, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, monospace;
}
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}
body {
  font-family: var(--font-body);
  background: var(--cream);
  color: var(--ink);
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}
.page {
  max-width: 760px;
  margin: 0 auto;
  padding: 40px 24px 64px;
}

.head {
  text-align: center;
  margin-bottom: 28px;
}
.kicker {
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--terracotta);
  font-weight: 700;
  margin-bottom: 8px;
}
.head h1 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.8rem, 4.5vw, 2.5rem);
  letter-spacing: -0.015em;
}
.sub {
  margin-top: 10px;
  font-size: 0.96rem;
  color: var(--warm-gray);
  max-width: 540px;
  margin-left: auto;
  margin-right: auto;
}

/* Filter */
.filter {
  background: var(--bone);
  border: 1px solid rgba(44, 26, 14, 0.08);
  border-radius: 14px;
  padding: 20px 22px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin-bottom: 22px;
}
.bank {
  border: none;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  align-items: center;
}
.bank legend {
  font-size: 0.7rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-2);
  font-weight: 700;
  margin-bottom: 4px;
  flex-basis: 100%;
}

.chip {
  display: inline-flex;
  align-items: center;
  background: var(--cream);
  border: 1px solid rgba(44, 26, 14, 0.12);
  padding: 8px 14px;
  border-radius: 999px;
  font-size: 0.88rem;
  font-weight: 600;
  cursor: pointer;
  user-select: none;
  transition: background 0.15s, color 0.15s, border-color 0.15s;
}
.chip input {
  display: none;
}
.chip:has(input:checked) {
  background: var(--forest);
  color: var(--bone);
  border-color: var(--forest-d);
}
.chip:hover {
  border-color: var(--terracotta);
}
.chip-avoid:has(input:checked) {
  background: var(--terracotta);
  color: var(--bone);
  border-color: var(--terracotta-d);
}

.counter {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-top: 1px dashed rgba(44, 26, 14, 0.18);
  padding-top: 14px;
  font-size: 0.92rem;
}
.counter b {
  font-family: var(--font-mono);
  font-weight: 800;
  color: var(--ink);
}
.counter .ok {
  color: var(--success);
  font-weight: 700;
}
.reset {
  background: transparent;
  border: 1px solid rgba(44, 26, 14, 0.16);
  color: var(--ink-2);
  border-radius: 999px;
  padding: 7px 14px;
  font-family: inherit;
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
}
.reset:hover {
  border-color: var(--terracotta);
  color: var(--terracotta-d);
}

/* List */
.list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}
@media (max-width: 640px) {
  .list {
    grid-template-columns: 1fr;
  }
}
.dish {
  background: var(--bone);
  border: 1px solid rgba(44, 26, 14, 0.08);
  border-radius: 12px;
  padding: 16px 18px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  transition: opacity 0.18s, background 0.18s, border-color 0.18s;
}
.dish.is-hidden {
  background: var(--cream-2);
  border-color: rgba(44, 26, 14, 0.06);
  opacity: 0.55;
}
.d-top {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 12px;
}
.d-name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.1rem;
}
.d-price {
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--terracotta-d);
}
.dish.is-hidden .d-price {
  color: var(--warm-gray);
}
.d-desc {
  font-size: 0.86rem;
  color: var(--ink-2);
}
.d-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 5px;
  margin-top: 4px;
}
.d-tag {
  font-size: 0.62rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  background: var(--cream-2);
  color: var(--ink-2);
  padding: 3px 8px;
  border-radius: 999px;
  font-weight: 700;
}
.d-tag[data-tone="veg"] {
  background: rgba(79, 122, 58, 0.16);
  color: var(--success);
}
.d-tag[data-tone="vegan"] {
  background: rgba(79, 122, 58, 0.24);
  color: var(--forest-d);
}
.d-tag[data-tone="gf"] {
  background: rgba(201, 168, 76, 0.2);
  color: #8a7325;
}
.d-tag[data-tone="signature"] {
  background: var(--gold);
  color: var(--ink);
}
.d-reason {
  margin-top: 4px;
  font-size: 0.78rem;
  color: var(--danger);
  font-weight: 600;
  font-style: italic;
}
.dish:not(.is-hidden) .d-reason {
  display: none;
}

// Dishes labelled with what they CONTAIN and what diets they are SUITABLE for.
// contains: any of dairy, nuts, shellfish, eggs, pork, gluten, spicy
// diet: vegan / vegetarian / gluten-free (it's safe for that diet)
const DISHES = [
  {
    name: "Pan masa madre",
    price: 8,
    desc: "Sourdough, smoked oil, sea salt.",
    contains: ["gluten"],
    diet: ["vegan", "vegetarian"],
    tags: [{ label: "Vegan", tone: "vegan" }],
  },
  {
    name: "Burrata huerta",
    price: 16,
    desc: "Heirloom tomato, garden basil, focaccia.",
    contains: ["dairy", "gluten"],
    diet: ["vegetarian"],
    tags: [{ label: "Veg", tone: "veg" }],
  },
  {
    name: "Pulpo a la brasa",
    price: 19,
    desc: "Charred octopus, paprika potato.",
    contains: ["shellfish"],
    diet: ["gluten-free"],
    tags: [{ label: "GF", tone: "gf" }],
  },
  {
    name: "Croquetas de jamón",
    price: 14,
    desc: "Iberico ham croquettes, lemon aioli.",
    contains: ["pork", "dairy", "gluten", "eggs"],
    diet: [],
    tags: [],
  },
  {
    name: "Ensalada huerta",
    price: 13,
    desc: "Garden lettuces, radish, lemon vinaigrette.",
    contains: [],
    diet: ["vegan", "vegetarian", "gluten-free"],
    tags: [
      { label: "Vegan", tone: "vegan" },
      { label: "GF", tone: "gf" },
    ],
  },
  {
    name: "Pappardelle al ragú",
    price: 24,
    desc: "Hand-cut pasta, slow lamb shoulder.",
    contains: ["gluten", "dairy", "eggs"],
    diet: [],
    tags: [],
  },
  {
    name: "Risotto de hongos",
    price: 26,
    desc: "Carnaroli rice, wild mushrooms, parmesan.",
    contains: ["dairy"],
    diet: ["vegetarian", "gluten-free"],
    tags: [
      { label: "Veg", tone: "veg" },
      { label: "GF", tone: "gf" },
    ],
  },
  {
    name: "Spaghetti alle vongole",
    price: 28,
    desc: "Clams, white wine, parsley.",
    contains: ["shellfish", "gluten"],
    diet: [],
    tags: [],
  },
  {
    name: "Ribeye 14oz",
    price: 48,
    desc: "Dry-aged 28 days, marrow butter, chimichurri.",
    contains: ["dairy"],
    diet: ["gluten-free"],
    tags: [
      { label: "GF", tone: "gf" },
      { label: "Signature", tone: "signature" },
    ],
  },
  {
    name: "Branzino entero",
    price: 38,
    desc: "Whole sea bass, fennel, preserved lemon.",
    contains: [],
    diet: ["gluten-free"],
    tags: [{ label: "GF", tone: "gf" }],
  },
  {
    name: "Pollo al carbón",
    price: 28,
    desc: "Half free-range chicken, garlic confit.",
    contains: [],
    diet: ["gluten-free"],
    tags: [{ label: "GF", tone: "gf" }],
  },
  {
    name: "Costilla de cordero",
    price: 42,
    desc: "Lamb ribs, honey-mint, charred onion.",
    contains: [],
    diet: ["gluten-free"],
    tags: [{ label: "GF", tone: "gf" }],
  },
  {
    name: "Plato del huerto",
    price: 22,
    desc: "Seasonal vegetables, chilli oil.",
    contains: ["spicy"],
    diet: ["vegan", "vegetarian", "gluten-free"],
    tags: [
      { label: "Vegan", tone: "vegan" },
      { label: "GF", tone: "gf" },
    ],
  },
  {
    name: "Tarta de queso quemada",
    price: 11,
    desc: "Basque burnt cheesecake.",
    contains: ["dairy", "eggs", "gluten"],
    diet: ["vegetarian"],
    tags: [
      { label: "Veg", tone: "veg" },
      { label: "Signature", tone: "signature" },
    ],
  },
  {
    name: "Olive oil cake",
    price: 10,
    desc: "Citrus, crème fraîche.",
    contains: ["dairy", "eggs", "gluten"],
    diet: ["vegetarian"],
    tags: [{ label: "Veg", tone: "veg" }],
  },
  {
    name: "Chocolate ganache",
    price: 12,
    desc: "Dark chocolate, hazelnut praline.",
    contains: ["dairy", "nuts"],
    diet: ["vegetarian", "gluten-free"],
    tags: [
      { label: "Veg", tone: "veg" },
      { label: "GF", tone: "gf" },
    ],
  },
];

const list = document.getElementById("list");
const okEl = document.getElementById("ok");
const hiddenEl = document.getElementById("hidden");

const AVOID_LABEL = {
  dairy: "Contains dairy",
  nuts: "Contains nuts",
  shellfish: "Contains shellfish",
  eggs: "Contains eggs",
  pork: "Contains pork",
  spicy: "Spicy",
  gluten: "Contains gluten",
};
const DIET_LABEL = {
  vegan: "not vegan",
  vegetarian: "not vegetarian",
  "gluten-free": "not gluten-free",
};

function evaluate() {
  const wants = [...document.querySelectorAll('input[name="diet"]:checked')].map((c) => c.value);
  const avoids = [...document.querySelectorAll('input[name="avoid"]:checked')].map((c) => c.value);

  let ok = 0;
  let hidden = 0;
  DISHES.forEach((d, i) => {
    const reasons = [];
    // Diet check: if user wants vegan, the dish must be vegan.
    wants.forEach((w) => {
      if (!d.diet.includes(w)) reasons.push(DIET_LABEL[w]);
    });
    // Avoid check
    avoids.forEach((a) => {
      if (d.contains.includes(a)) reasons.push(AVOID_LABEL[a]);
    });
    // GF avoid = also avoid gluten as an avoid
    if (wants.includes("gluten-free") && d.contains.includes("gluten")) {
      // already accounted for via diet; do nothing
    }
    const el = document.querySelector(`[data-i="${i}"]`);
    if (!el) return;
    const r = el.querySelector(".d-reason");
    if (reasons.length === 0) {
      el.classList.remove("is-hidden");
      if (r) r.textContent = "";
      ok += 1;
    } else {
      el.classList.add("is-hidden");
      if (r) r.textContent = `Why hidden · ${reasons.slice(0, 2).join(" · ")}`;
      hidden += 1;
    }
  });
  okEl.textContent = ok;
  hiddenEl.textContent = hidden;
}

function render() {
  list.innerHTML = DISHES.map(
    (d, i) => `<article class="dish" data-i="${i}">
      <div class="d-top">
        <span class="d-name">${d.name}</span>
        <span class="d-price">$${d.price.toFixed(2)}</span>
      </div>
      <p class="d-desc">${d.desc}</p>
      ${
        d.tags.length
          ? `<div class="d-tags">${d.tags.map((t) => `<span class="d-tag" data-tone="${t.tone}">${t.label}</span>`).join("")}</div>`
          : ""
      }
      <p class="d-reason"></p>
    </article>`
  ).join("");
}

document
  .querySelectorAll('input[type="checkbox"]')
  .forEach((cb) => cb.addEventListener("change", evaluate));
document.getElementById("reset").addEventListener("click", () => {
  document.querySelectorAll('input[type="checkbox"]').forEach((cb) => (cb.checked = false));
  evaluate();
});

render();
evaluate();

<!doctype html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <link rel="preconnect" href="https://fonts.googleapis.com" />
    <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin />
    <link
      rel="stylesheet"
      href="https://fonts.googleapis.com/css2?family=Playfair+Display:wght@700;800&family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@500;700&display=swap"
    />
    <link rel="stylesheet" href="style.css" />
    <title>Allergy filter · Casa Olivar</title>
  </head>
  <body>
    <main class="page">
      <header class="head">
        <p class="kicker">Tonight's carta · 16 dishes</p>
        <h1>Tell us what you avoid.</h1>
        <p class="sub">
          The kitchen can adapt most dishes — pick what you'd rather skip and
          we'll show you only what's safe.
        </p>
      </header>

      <section class="filter">
        <fieldset class="bank">
          <legend>I want</legend>
          <label class="chip" data-kind="diet">
            <input type="checkbox" name="diet" value="vegetarian" />
            <span>🥬 Vegetarian</span>
          </label>
          <label class="chip" data-kind="diet">
            <input type="checkbox" name="diet" value="vegan" />
            <span>🌱 Vegan</span>
          </label>
          <label class="chip" data-kind="diet">
            <input type="checkbox" name="diet" value="gluten-free" />
            <span>🌾 Gluten-free</span>
          </label>
        </fieldset>

        <fieldset class="bank">
          <legend>I avoid</legend>
          <label class="chip chip-avoid" data-kind="avoid">
            <input type="checkbox" name="avoid" value="dairy" />
            <span>🥛 Dairy</span>
          </label>
          <label class="chip chip-avoid" data-kind="avoid">
            <input type="checkbox" name="avoid" value="nuts" />
            <span>🥜 Nuts</span>
          </label>
          <label class="chip chip-avoid" data-kind="avoid">
            <input type="checkbox" name="avoid" value="shellfish" />
            <span>🦐 Shellfish</span>
          </label>
          <label class="chip chip-avoid" data-kind="avoid">
            <input type="checkbox" name="avoid" value="eggs" />
            <span>🥚 Eggs</span>
          </label>
          <label class="chip chip-avoid" data-kind="avoid">
            <input type="checkbox" name="avoid" value="pork" />
            <span>🐖 Pork</span>
          </label>
          <label class="chip chip-avoid" data-kind="avoid">
            <input type="checkbox" name="avoid" value="spicy" />
            <span>🌶 Spicy</span>
          </label>
        </fieldset>

        <div class="counter">
          <p>
            <b id="ok">16</b> of 16 dishes are <span class="ok">safe</span> · <b id="hidden">0</b> hidden
          </p>
          <button class="reset" type="button" id="reset">Reset filters</button>
        </div>
      </section>

      <section class="list" id="list"></section>
    </main>
    <script src="script.js"></script>
  </body>
</html>

Allergy & Diet Filter

The widget a diner taps before browsing the menu. Two chip rows: “I want” (Vegetarian · Vegan · Gluten-free) and “I avoid” (Dairy · Nuts · Shellfish · Eggs · Pork · Spicy). Live counter shows how many of the 16 menu items match. Result list shows safe dishes; hidden ones get a muted card with a one-line “Why hidden” explanation. Adapts the carta in place — no full re-render.