.toast-stack {
    position: fixed;
    right: var(--space-4);
    top: var(--space-4);
    width: min(520px, calc(100% - var(--space-8)));
    display: grid;
    gap: var(--space-2);
    z-index: 2200;
  }

  .toast {
    border: 1px solid var(--border-default);
    border-radius: var(--radius-lg);
    background: var(--surface-glass-2);
    -webkit-backdrop-filter: blur(12px) saturate(130%);
    backdrop-filter: blur(12px) saturate(130%);
    overflow: hidden;
    box-shadow: 0 12px 24px rgba(0, 0, 0, 0.4);
    animation: toast-in 250ms ease-out;
    transition: opacity 200ms ease, transform 200ms ease;
  }

  .toast.is-leaving {
    opacity: 0;
    transform: translateX(40px);
  }

  .toast--ok {
    border-color: rgba(74, 222, 128, 0.25);
    background:
      linear-gradient(0deg, var(--ok-soft), var(--ok-soft)),
      var(--surface-glass-2);
    color: var(--ok);
  }

  .toast--error {
    border-color: rgba(251, 113, 133, 0.25);
    background:
      linear-gradient(0deg, var(--danger-soft), var(--danger-soft)),
      var(--surface-glass-2);
    color: var(--danger);
  }

  .toast--warning {
    border-color: rgba(251, 191, 36, 0.25);
    background:
      linear-gradient(0deg, var(--warning-soft), var(--warning-soft)),
      var(--surface-glass-2);
    color: var(--warning);
  }

  .toast--info {
    border-color: rgba(56, 189, 248, 0.25);
    background:
      linear-gradient(0deg, var(--info-soft), var(--info-soft)),
      var(--surface-glass-2);
    color: var(--info);
  }

  .toast-content {
    display: flex;
    gap: var(--space-3);
    align-items: flex-start;
    justify-content: space-between;
    padding: var(--space-3);
    /* Compensates for the 3px timer bar below + optical alignment. */
    padding-bottom: calc(var(--space-3) - 6px);
  }

  .toast-message {
    margin: 0;
    font-size: var(--text-sm);
    line-height: var(--leading-snug);
  }

  .toast-close {
    appearance: none;
    -webkit-appearance: none;
    border: 1px solid var(--border-default);
    background: var(--surface-2);
    color: var(--shell-muted);
    width: 24px;
    height: 24px;
    min-width: 24px;
    min-height: 24px;
    border-radius: var(--radius-md);
    padding: 0;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    line-height: 1;
    font-family: inherit;
    cursor: pointer;
  }

  .toast-close .toast-close-icon {
    width: 12px;
    height: 12px;
  }

  .toast-close:hover {
    background: var(--surface-3);
    border-color: var(--surface-3);
    color: var(--shell-ink);
  }

  .toast-close:focus-visible {
    outline: 2px solid var(--focus-ring);
    outline-offset: 1px;
  }

  .toast-timer {
    height: 3px;
    background: rgba(255, 255, 255, 0.06);
  }

  .toast-timer-bar {
    display: block;
    height: 100%;
    width: 100%;
    transform-origin: left center;
  }

  .toast--ok .toast-timer-bar {
    background: var(--ok);
  }

  .toast--error .toast-timer-bar {
    background: var(--danger);
  }

  .toast--warning .toast-timer-bar {
    background: var(--warning);
  }

  .toast--info .toast-timer-bar {
    background: var(--info);
  }

  .toast.is-expiring .toast-timer-bar {
    transition: transform linear;
    transform: scaleX(0);
  }

  @supports not ((-webkit-backdrop-filter: blur(1px)) or (backdrop-filter: blur(1px))) {
    .toast {
      background: var(--surface-1);
    }

    .toast--ok {
      background:
        linear-gradient(0deg, var(--ok-soft), var(--ok-soft)),
        var(--surface-1);
    }

    .toast--error {
      background:
        linear-gradient(0deg, var(--danger-soft), var(--danger-soft)),
        var(--surface-1);
    }

    .toast--warning {
      background:
        linear-gradient(0deg, var(--warning-soft), var(--warning-soft)),
        var(--surface-1);
    }

    .toast--info {
      background:
        linear-gradient(0deg, var(--info-soft), var(--info-soft)),
        var(--surface-1);
    }
  }

  @keyframes toast-in {
    from {
      opacity: 0;
      transform: translateY(-12px);
    }
    to {
      opacity: 1;
      transform: translateY(0);
    }
  }