/* Mobile Playground — shared stylesheet
   Loaded by the landing page and every tool page (../../assets/style.css).
   Mobile-first. Light/dark follows the OS. Keep it dependency-free. */

:root {
  color-scheme: light dark;

  --bg: #f6f7f9;
  --surface: #ffffff;
  --surface-2: #eef0f4;
  --text: #16181d;
  --muted: #5f6572;
  --border: #d9dde5;
  --accent: #2563eb;
  --accent-contrast: #ffffff;
  --danger: #dc2626;
  --ok: #16a34a;

  --radius: 12px;
  --gap: 12px;
  --maxw: 760px;
  --tap: 44px;                    /* minimum touch target */
  --font: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1115;
    --surface: #181b21;
    --surface-2: #22262e;
    --text: #e8eaef;
    --muted: #9aa1ad;
    --border: #2e333d;
    --accent: #60a5fa;
    --accent-contrast: #0b1220;
    --danger: #f87171;
    --ok: #4ade80;
  }
}

*, *::before, *::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;               /* 16px+ stops iOS zooming into inputs */
  line-height: 1.5;
  color: var(--text);
  background: var(--bg);
  padding: env(safe-area-inset-top) env(safe-area-inset-right)
           env(safe-area-inset-bottom) env(safe-area-inset-left);
}

.container {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 16px;
}

/* ---- Header / footer ------------------------------------------------- */

.site-header { padding: 8px 0 16px; }
.site-header h1 { margin: 0 0 4px; font-size: 1.6rem; line-height: 1.2; }
.site-header p  { margin: 0; color: var(--muted); }

.back-link {
  display: inline-flex; align-items: center; gap: 6px;
  min-height: var(--tap); color: var(--muted); text-decoration: none;
}
.back-link:hover, .back-link:focus-visible { color: var(--accent); }

.site-footer {
  margin-top: 32px; padding-top: 16px;
  border-top: 1px solid var(--border);
  color: var(--muted); font-size: 0.875rem;
}
.site-footer a { color: inherit; }

/* ---- Typography ------------------------------------------------------ */

h1, h2, h3 { line-height: 1.25; }
h2 { font-size: 1.2rem; margin: 24px 0 8px; }
a  { color: var(--accent); }
code, pre, .mono { font-family: var(--mono); font-size: 0.9375em; }
pre {
  background: var(--surface-2); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 12px; overflow-x: auto;
}
.muted { color: var(--muted); }
.small { font-size: 0.875rem; }

/* ---- Cards / grid ---------------------------------------------------- */

.grid {
  display: grid; gap: var(--gap);
  grid-template-columns: 1fr;
}
@media (min-width: 560px) {
  .grid { grid-template-columns: repeat(2, 1fr); }
}

.card {
  display: block;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
  color: inherit; text-decoration: none;
}
a.card:hover, a.card:focus-visible {
  border-color: var(--accent);
  outline: none;
}
.card-title {
  display: flex; align-items: center; gap: 10px;
  font-weight: 600; font-size: 1.05rem; margin: 0 0 4px;
}
.card-icon { font-size: 1.4rem; line-height: 1; }
.card-desc { margin: 0; color: var(--muted); }
.card-meta { margin: 8px 0 0; display: flex; flex-wrap: wrap; gap: 6px; }

.tag {
  display: inline-block; font-size: 0.75rem; padding: 2px 8px;
  border-radius: 999px; background: var(--surface-2); color: var(--muted);
}

/* ---- Forms / controls ------------------------------------------------ */

label { display: block; font-weight: 600; margin: 12px 0 4px; }

input, select, textarea, button {
  font: inherit; color: inherit;
}
input[type="text"], input[type="search"], input[type="number"],
input[type="url"], input[type="email"], input[type="datetime-local"],
select, textarea {
  width: 100%; min-height: var(--tap);
  padding: 10px 12px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
input:focus-visible, select:focus-visible, textarea:focus-visible,
button:focus-visible {
  outline: 2px solid var(--accent); outline-offset: 2px;
}
textarea { min-height: 120px; resize: vertical; }

button, .btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  min-height: var(--tap); padding: 10px 16px;
  background: var(--accent); color: var(--accent-contrast);
  border: 0; border-radius: var(--radius);
  cursor: pointer; text-decoration: none; font-weight: 600;
  -webkit-tap-highlight-color: transparent;
}
button:disabled { opacity: 0.5; cursor: not-allowed; }
.btn-secondary {
  background: var(--surface-2); color: var(--text);
  border: 1px solid var(--border);
}
.row { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }
.row > * { flex: 1 1 auto; }

/* ---- Utilities ------------------------------------------------------- */

.result {
  margin-top: 12px; padding: 12px 14px;
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); word-break: break-word;
}
.error { color: var(--danger); }
.ok    { color: var(--ok); }
.hidden { display: none !important; }
.visually-hidden {
  position: absolute; width: 1px; height: 1px; overflow: hidden;
  clip: rect(0 0 0 0); white-space: nowrap;
}