Alerts and toasts

<div class="alerts">
  <div class="alert info">
    <svg viewBox="0 0 24 24" aria-hidden="true"><circle cx="12" cy="12" r="9"/><path d="M12 11v5M12 8h.01"/></svg>
    <div><strong>Scheduled maintenance</strong>
      <p>The API will be read-only on Sunday between 02:00 and 04:00 UTC.</p></div>
  </div>

  <div class="alert ok" role="status">
    <svg viewBox="0 0 24 24" aria-hidden="true"><circle cx="12" cy="12" r="9"/><path d="M8.5 12.5l2.5 2.5 4.5-5"/></svg>
    <div><strong>Project deployed</strong>
      <p>Live at <a href="#">acme.example.com</a> — took 38 seconds.</p></div>
  </div>

  <div class="alert warn">
    <svg viewBox="0 0 24 24" aria-hidden="true"><path d="M12 4l9 16H3z"/><path d="M12 10v4M12 17h.01"/></svg>
    <div><strong>Your card expires next month</strong>
      <p><a href="#">Update your payment details</a> to avoid an interruption.</p></div>
    <button class="close" type="button" aria-label="Dismiss this notice">&times;</button>
  </div>

  <div class="alert bad" role="alert">
    <svg viewBox="0 0 24 24" aria-hidden="true"><circle cx="12" cy="12" r="9"/><path d="M15 9l-6 6M9 9l6 6"/></svg>
    <div><strong>Build failed</strong>
      <p>Module not found: <code>./utils/format</code> at line 12 of <code>app.js</code>.</p></div>
  </div>
</div>

<div class="try">
  <button class="btn" type="button" data-toast="ok">Show a success toast</button>
  <button class="btn ghost" type="button" data-toast="bad">Show an error toast</button>
</div>

<!-- toasts land here; the region exists from page load so it is watched -->
<div class="toasts" id="toasts" role="region" aria-label="Notifications"></div>

* { box-sizing: border-box; margin: 0; }
body { font: 16px/1.6 system-ui, -apple-system, sans-serif; padding: 22px; background: #f6f8fb; }

.alerts { max-width: 620px; margin: 0 auto; display: grid; gap: 12px; }

/* ============ inline alert ============ */
.alert {
  --tint: #eef1f6;
  --line: #dbe2ec;
  --ink: #5b6b83;

  display: flex;
  gap: 12px;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-left: 3px solid var(--ink);
  border-radius: 10px;
  background: var(--tint);
}

.alert.info { --tint: #eef0fe; --line: #dbe0fd; --ink: #2a3abf; }
.alert.ok   { --tint: #eaf7f1; --line: #cdeade; --ink: #1a7a50; }
.alert.warn { --tint: #fdf6e7; --line: #f5e4bd; --ink: #9a6414; }
.alert.bad  { --tint: #fdeeee; --line: #f6d5d5; --ink: #b03535; }

.alert svg {
  width: 19px; height: 19px;
  flex-shrink: 0;
  margin-top: 2px;
  fill: none;
  stroke: var(--ink);
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.alert strong { display: block; font-size: .93rem; color: #16202e; }
.alert p { font-size: .88rem; color: var(--ink); margin-top: 2px; }
.alert a { color: var(--ink); font-weight: 500; }
.alert code { background: rgba(255,255,255,.7); padding: 1px 5px; border-radius: 4px; font-size: .88em; }

.close {
  margin-left: auto;
  align-self: flex-start;
  width: 26px; height: 26px;
  display: grid; place-items: center;
  font: inherit; font-size: 1.1rem; line-height: 1;
  border: 0; border-radius: 6px;
  background: none;
  color: var(--ink);
  opacity: .6;
  cursor: pointer;
}

.close:hover { opacity: 1; background: rgba(255,255,255,.6); }
.close:focus-visible { outline: 2px solid currentColor; outline-offset: 1px; }

/* ============ toasts ============ */
.try { max-width: 620px; margin: 22px auto 0; display: flex; gap: 10px; flex-wrap: wrap; }

.btn {
  font: inherit; font-size: .92rem; font-weight: 500;
  padding: 10px 20px; min-height: 40px;
  border: 1px solid #3b4fe4; border-radius: 9px;
  background: #3b4fe4; color: #fff; cursor: pointer;
}
.btn:hover { background: #2a3abf; border-color: #2a3abf; }
.btn.ghost { background: #fff; color: #16202e; border-color: #d9e0ea; }
.btn.ghost:hover { background: #f2f5f9; }

.toasts {
  position: fixed;
  right: 16px;
  bottom: 16px;
  z-index: 100;
  display: grid;
  gap: 10px;
  justify-items: end;
  pointer-events: none;      /* the stack must not block the page */
}

.toast {
  pointer-events: auto;      /* the toasts themselves are clickable */
  display: flex;
  align-items: center;
  gap: 10px;
  max-width: 340px;
  padding: 12px 14px;
  border-radius: 10px;
  background: #16202e;
  color: #fff;
  font-size: .89rem;
  box-shadow: 0 4px 8px rgba(22,32,46,.1), 0 18px 40px -22px rgba(22,32,46,.7);
  animation: rise .22s ease-out;
}

.toast.bad { background: #b03535; }
.toast .x { margin-left: auto; border: 0; background: none; color: inherit; opacity: .6;
            font-size: 1.05rem; line-height: 1; cursor: pointer; padding: 2px 4px; }
.toast .x:hover { opacity: 1; }

@keyframes rise { from { opacity: 0; transform: translateY(10px); } }

@media (prefers-reduced-motion: reduce) {
  .toast { animation: none; }
}

@media (max-width: 480px) {
  .toasts { left: 16px; justify-items: stretch; }
  .toast { max-width: none; }
}

// dismissable inline alerts
document.querySelectorAll(".alert .close").forEach((b) => {
  b.addEventListener("click", () => b.closest(".alert").remove());
});

const stack = document.getElementById("toasts");

function toast(message, kind = "ok", ms = 4000) {
  const el = document.createElement("div");
  el.className = "toast " + kind;
  // errors interrupt; confirmations wait for a pause
  el.setAttribute("role", kind === "bad" ? "alert" : "status");

  const text = document.createElement("span");
  text.textContent = message;

  const close = document.createElement("button");
  close.className = "x";
  close.type = "button";
  close.setAttribute("aria-label", "Dismiss");
  close.textContent = "\u00d7";
  close.addEventListener("click", () => el.remove());

  el.append(text, close);
  stack.append(el);

  // errors stay until dismissed; anything else clears itself
  if (kind !== "bad") setTimeout(() => el.remove(), ms);
}

document.querySelectorAll("[data-toast]").forEach((b) => {
  b.addEventListener("click", () => {
    b.dataset.toast === "bad"
      ? toast("Could not save — the server did not respond.", "bad")
      : toast("Saved. Your changes are live.", "ok");
  });
});