/* ── StuGar · shared UI kit ──────────────────────────────────────────────────
   Components every module was previously re-implementing: buttons, cards,
   badges, empty states, skeletons, and the shells for ui.js's toast + dialog.
   Everything resolves against /tokens.css, so link that first:

       <link rel="stylesheet" href="/tokens.css">
       <link rel="stylesheet" href="/ui.css">
       <script src="/ui.js" defer></script>

   Class names are prefixed sg- so they can't collide with a page's existing
   .btn / .badge / .modal rules during migration.
   ──────────────────────────────────────────────────────────────────────────── */

/* ── Focus baseline ────────────────────────────────────────────────────────────
   The app had no :focus-visible rule anywhere and 25 `outline:none` declarations
   removing the default ring, leaving keyboard users with a 1.5px border tint.
   This restores a visible ring for keyboard focus only — mouse clicks stay clean
   because :focus-visible doesn't match them. !important is deliberate: this is an
   accessibility floor, and it has to beat the per-page `outline:none` rules that
   load after this file. Pages set nothing on :focus-visible, so nothing conflicts. */
:is(a[href], button, input, select, textarea, summary, [tabindex]):focus-visible {
  outline: 2px solid var(--accent) !important;
  outline-offset: 2px !important;
  border-radius: inherit;
}

/* ── Buttons ───────────────────────────────────────────────────────────────── */
.sg-btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  padding: 8px 14px; min-height: 40px;            /* 40px keeps it thumb-sized */
  border: 1.5px solid var(--border); border-radius: var(--r-md);
  background: var(--surface); color: var(--text);
  font-family: var(--font); font-size: var(--fs-sm); font-weight: 700;
  cursor: pointer; text-decoration: none; white-space: nowrap;
  transition: background .15s, border-color .15s, color .15s, opacity .15s;
}
.sg-btn:hover:not(:disabled) { border-color: var(--accent); color: var(--accent); }
.sg-btn:disabled { opacity: .5; cursor: default; }
.sg-btn:focus-visible { outline: var(--focus); outline-offset: var(--focus-offset); }

.sg-btn--primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.sg-btn--primary:hover:not(:disabled) { filter: brightness(1.08); color: #fff; }
.sg-btn--danger { background: var(--danger); border-color: var(--danger); color: #fff; }
.sg-btn--danger:hover:not(:disabled) { filter: brightness(1.08); color: #fff; }
.sg-btn--ghost { background: transparent; border-color: transparent; color: var(--muted); }
.sg-btn--ghost:hover:not(:disabled) { background: var(--surface2); color: var(--text); }
.sg-btn--sm { padding: 5px 10px; min-height: 32px; font-size: var(--fs-xs); border-radius: var(--r-sm); }

/* ── Card ──────────────────────────────────────────────────────────────────── */
.sg-card {
  background: var(--surface); border: 1.5px solid var(--border);
  border-radius: var(--r-lg); padding: var(--sp-4);
}

/* ── Badges ────────────────────────────────────────────────────────────────── */
.sg-badge {
  display: inline-block; padding: 2px 7px; border-radius: var(--r-sm);
  font-size: var(--fs-xs); font-weight: 700; letter-spacing: .02em;
  background: var(--surface2); color: var(--muted);
}
.sg-badge--ok     { background: color-mix(in srgb, var(--success) 16%, transparent); color: var(--success); }
.sg-badge--warn   { background: color-mix(in srgb, var(--warn) 18%, transparent);    color: var(--warn); }
.sg-badge--danger { background: color-mix(in srgb, var(--danger) 16%, transparent);  color: var(--danger); }
.sg-badge--info   { background: color-mix(in srgb, var(--info) 16%, transparent);    color: var(--info); }

/* ── Empty state ───────────────────────────────────────────────────────────── */
.sg-empty { text-align: center; padding: 36px 16px; color: var(--muted); font-size: var(--fs-sm); }
.sg-empty__icon { font-size: 2.4rem; line-height: 1; margin-bottom: 8px; }

/* ── Skeleton ──────────────────────────────────────────────────────────────── */
.sg-skeleton {
  height: 14px; border-radius: var(--r-sm);
  background: linear-gradient(90deg, var(--surface2), var(--border), var(--surface2));
  background-size: 200% 100%; animation: sg-sh 1.2s infinite;
}
@keyframes sg-sh { 0% { background-position: 200% 0 } 100% { background-position: -200% 0 } }

/* ── Toast (driven by ui.js) ───────────────────────────────────────────────── */
.sg-toasts {
  position: fixed; left: 50%; transform: translateX(-50%);
  bottom: calc(20px + env(safe-area-inset-bottom));
  z-index: 900; display: flex; flex-direction: column; gap: 8px;
  align-items: center; pointer-events: none; width: max-content; max-width: 92vw;
}
.sg-toast {
  background: #0f172a; color: #fff; padding: 10px 18px;
  border-radius: var(--r-md); font-size: var(--fs-sm); font-weight: 600;
  box-shadow: var(--shadow-2); opacity: 0; transition: opacity .2s, transform .2s;
  transform: translateY(6px); text-align: center;
}
.sg-toast.is-in { opacity: 1; transform: none; }
.sg-toast--error { background: var(--danger); }
.sg-toast--success { background: var(--success); color: #05261d; }

/* ── Dialog (driven by ui.js) ──────────────────────────────────────────────── */
.sg-dialog-bg {
  position: fixed; inset: 0; z-index: 950;
  background: rgba(15, 23, 42, .55);
  display: flex; align-items: center; justify-content: center;
  padding: calc(18px + env(safe-area-inset-top)) 18px calc(18px + env(safe-area-inset-bottom));
  opacity: 0; transition: opacity .15s;
  overscroll-behavior: contain;
}
.sg-dialog-bg.is-in { opacity: 1; }
.sg-dialog {
  background: var(--surface); color: var(--text);
  border: 1.5px solid var(--border); border-radius: var(--r-lg);
  box-shadow: var(--shadow-3); padding: 20px;
  width: 100%; max-width: 380px;
  max-height: calc(100vh - 36px); overflow-y: auto;
  font-family: var(--font); font-size: var(--fs-body);
  transform: translateY(8px) scale(.98); transition: transform .15s;
}
.sg-dialog-bg.is-in .sg-dialog { transform: none; }
.sg-dialog__title { font-size: var(--fs-title); font-weight: 700; margin: 0 0 8px; }
.sg-dialog__body  { color: var(--muted); font-size: var(--fs-sm); line-height: 1.5; white-space: pre-wrap; }
.sg-dialog__input {
  width: 100%; box-sizing: border-box; margin-top: 12px;
  padding: 9px 10px; border: 1.5px solid var(--border); border-radius: var(--r-md);
  background: var(--bg); color: var(--text); font-family: var(--font); font-size: 1rem;
}
.sg-dialog__input:focus-visible { outline: var(--focus); outline-offset: 1px; border-color: var(--accent); }
.sg-dialog__actions { display: flex; gap: 8px; justify-content: flex-end; margin-top: 18px; flex-wrap: wrap; }
.sg-dialog__actions .sg-btn { flex: 1 1 auto; }

@media (prefers-reduced-motion: reduce) {
  .sg-toast, .sg-dialog-bg, .sg-dialog { transition: none; }
  .sg-skeleton { animation: none; }
}