:root {
  color-scheme: dark light;

  /* Dark palette (default) */
  --bg: #0b0f17;
  --bg-elev: #11161f;
  --panel: #141a25;
  --panel-2: #1a212e;
  --border: #232a38;
  --border-strong: #2f3849;
  --fg: #e6edf6;
  --fg-dim: #b1bccb;
  --fg-muted: #7d8aa0;
  --accent: #8b5cf6;
  --accent-2: #06b6d4;
  --accent-fg: #ffffff;
  --danger: #ef4444;
  --ok: #22c55e;

  --radius: 10px;
  --radius-sm: 6px;
  --shadow-1: 0 1px 2px rgba(0, 0, 0, 0.4), 0 8px 24px rgba(0, 0, 0, 0.25);

  --mono: ui-monospace, "JetBrains Mono", "SF Mono", Menlo, Consolas, monospace;
  --sans: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Inter, sans-serif;
}

:root[data-theme="light"] {
  --bg: #f7f8fa;
  --bg-elev: #ffffff;
  --panel: #ffffff;
  --panel-2: #f6f8fa;
  --border: #e3e7ed;
  --border-strong: #cdd5e0;
  --fg: #0f172a;
  --fg-dim: #334155;
  --fg-muted: #64748b;
  --accent: #7c3aed;
  --accent-2: #0891b2;
  --accent-fg: #ffffff;
  --danger: #dc2626;
  --shadow-1: 0 1px 2px rgba(15, 23, 42, 0.04), 0 8px 24px rgba(15, 23, 42, 0.06);
}

@media (prefers-color-scheme: light) {
  :root:not([data-theme]) {
    --bg: #f7f8fa;
    --bg-elev: #ffffff;
    --panel: #ffffff;
    --panel-2: #f6f8fa;
    --border: #e3e7ed;
    --border-strong: #cdd5e0;
    --fg: #0f172a;
    --fg-dim: #334155;
    --fg-muted: #64748b;
    --accent: #7c3aed;
    --accent-2: #0891b2;
    --accent-fg: #ffffff;
    --danger: #dc2626;
    --shadow-1: 0 1px 2px rgba(15, 23, 42, 0.04), 0 8px 24px rgba(15, 23, 42, 0.06);
  }
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  height: 100%;
}

body {
  background: var(--bg);
  color: var(--fg);
  font: 15px/1.55 var(--sans);
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  min-height: 100dvh;
}

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover,
a:focus-visible {
  text-decoration: underline;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 4px;
}

::selection {
  background: var(--accent);
  color: var(--accent-fg);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ─────────── Topbar ─────────── */

.topbar {
  position: sticky;
  top: 0;
  z-index: 10;
  background: color-mix(in srgb, var(--bg) 90%, transparent);
  backdrop-filter: saturate(180%) blur(10px);
  border-bottom: 1px solid var(--border);
}

.topbar-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 12px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--fg);
  font-weight: 600;
}

.brand:hover {
  text-decoration: none;
}

.brand-mark {
  width: 28px;
  height: 28px;
  border-radius: 8px;
  display: grid;
  place-items: center;
  color: white;
  font-family: var(--sans);
  font-weight: 800;
  font-size: 16px;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  box-shadow: 0 2px 8px rgba(124, 58, 237, 0.35);
}

.brand-name {
  letter-spacing: -0.01em;
}

.brand-tag {
  color: var(--fg-muted);
  font-weight: 500;
  font-size: 13px;
  padding-left: 8px;
  border-left: 1px solid var(--border);
  margin-left: 4px;
}

.topbar-links {
  display: flex;
  align-items: center;
  gap: 4px;
}

.topbar-links a {
  color: var(--fg-dim);
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  font-size: 14px;
}

.topbar-links a:hover {
  color: var(--fg);
  background: var(--panel-2);
  text-decoration: none;
}

/* ─────────── Hero ─────────── */

.hero {
  border-bottom: 1px solid var(--border);
  background:
    radial-gradient(900px 220px at 20% -40%, rgba(124, 58, 237, 0.18), transparent 70%),
    radial-gradient(700px 220px at 90% -20%, rgba(6, 182, 212, 0.14), transparent 70%);
}

.hero-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 36px 24px 28px;
}

.hero h1 {
  margin: 0;
  font-size: clamp(1.6rem, 2.4vw + 0.6rem, 2.25rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  background: linear-gradient(90deg, var(--fg), var(--accent));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero p {
  margin: 10px 0 0;
  max-width: 760px;
  color: var(--fg-dim);
  font-size: 15px;
}

/* ─────────── Layout ─────────── */

.layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  padding: 16px 24px 24px;
  max-width: 1280px;
  width: 100%;
  margin: 0 auto;
  min-height: 0;
}

/* Sticky footer: when total content is shorter than the viewport, the
   auto top-margin on the footer absorbs the slack so the footer stays
   pinned to the bottom. When content overflows, the auto margin
   collapses to 0 and the footer sits right after the content. */
.footer {
  margin-top: auto;
}

/* Desktop only: let the layout grow to fill the viewport so panels
   feel proportional on big screens. On mobile we keep natural heights
   so panels stack without dead space. */
@media (min-width: 901px) {
  .layout {
    flex: 1 1 auto;
  }
}

@media (max-width: 900px) {
  /* Stack panels vertically. flex: 0 0 auto stops the layout from
     growing past its content, so the footer sits right under the
     last panel instead of floating with dead space above it. */
  .layout {
    display: flex;
    flex-direction: column;
    flex: 0 0 auto;
    padding: 12px;
    gap: 12px;
  }
}

.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-1);
  display: flex;
  flex-direction: column;
  min-height: 460px;
  overflow: hidden;
}

.panel-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 12px 14px;
  border-bottom: 1px solid var(--border);
  background: var(--panel-2);
}

.panel-title {
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.panel-title h2 {
  margin: 0;
  font-size: 13px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--fg-dim);
}

.dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  display: inline-block;
}

.dot-in {
  background: var(--accent);
  box-shadow: 0 0 12px rgba(124, 58, 237, 0.6);
}

.dot-out {
  background: var(--accent-2);
  box-shadow: 0 0 12px rgba(6, 182, 212, 0.5);
}

.panel-actions {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

/* ─────────── Controls ─────────── */

.controls {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 16px;
  align-items: center;
  padding: 12px 14px;
  border-bottom: 1px solid var(--border);
  background: var(--panel);
}

.field {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--fg-muted);
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.field select {
  text-transform: none;
  letter-spacing: 0;
}

select {
  appearance: none;
  background: var(--bg-elev);
  color: var(--fg);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  padding: 6px 28px 6px 10px;
  font: inherit;
  font-size: 13px;
  cursor: pointer;
  background-image: linear-gradient(45deg, transparent 50%, var(--fg-muted) 50%),
    linear-gradient(135deg, var(--fg-muted) 50%, transparent 50%);
  background-position: calc(100% - 16px) 50%, calc(100% - 11px) 50%;
  background-size: 5px 5px;
  background-repeat: no-repeat;
}

select:hover {
  border-color: var(--accent);
}

.select-wrap {
  display: inline-block;
}

.chips {
  border: 0;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  align-items: center;
}

.chips legend {
  color: var(--fg-muted);
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  padding: 0 6px 0 0;
  float: left;
}

.chips label {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 10px;
  background: var(--bg-elev);
  border: 1px solid var(--border-strong);
  border-radius: 999px;
  font: 12px var(--mono);
  color: var(--fg-dim);
  cursor: pointer;
  user-select: none;
  transition: background 120ms, border-color 120ms, color 120ms;
}

.chips label:hover {
  border-color: var(--accent);
  color: var(--fg);
}

.chips input[type="checkbox"] {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

.chips label:has(input:checked) {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  border-color: transparent;
  color: var(--accent-fg);
  box-shadow: 0 2px 10px rgba(124, 58, 237, 0.35);
}

.chips input:focus-visible + span,
.chips label:focus-within {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 999px;
}

/* ─────────── Source textarea ─────────── */

textarea {
  flex: 1;
  width: 100%;
  min-height: 280px;
  resize: none;
  border: 0;
  background: var(--panel);
  color: var(--fg);
  font: 13px/1.6 var(--mono);
  padding: 16px;
  outline: none;
  tab-size: 2;
}

textarea::placeholder {
  color: var(--fg-muted);
}

/* ─────────── Output ─────────── */

.tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  padding: 10px 14px;
  border-bottom: 1px solid var(--border);
  background: var(--panel);
  min-height: 50px;
}

.tabs button {
  background: var(--bg-elev);
  border: 1px solid var(--border-strong);
  color: var(--fg-dim);
  padding: 5px 12px;
  font: 12px var(--mono);
  border-radius: 999px;
  cursor: pointer;
  transition: background 120ms, border-color 120ms, color 120ms;
}

.tabs button:hover {
  border-color: var(--accent);
  color: var(--fg);
}

.tabs button[aria-selected="true"] {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  border-color: transparent;
  color: var(--accent-fg);
  box-shadow: 0 2px 10px rgba(6, 182, 212, 0.35);
}

.file-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 8px 14px;
  border-bottom: 1px solid var(--border);
  background: var(--panel-2);
  min-height: 40px;
}

.file-select select {
  font-family: var(--mono);
  font-size: 12px;
  background: var(--panel);
}

.filemeta {
  color: var(--fg-muted);
  font: 12px var(--mono);
}

#content {
  flex: 1;
  margin: 0;
  padding: 16px 18px;
  white-space: pre-wrap;
  overflow: auto;
  font: 13px/1.6 var(--mono);
  color: var(--fg);
  background: var(--panel);
}

#content:empty::before {
  content: "No output yet.";
  color: var(--fg-muted);
  font-style: italic;
}

/* ─────────── Buttons ─────────── */

.ghost {
  appearance: none;
  background: var(--bg-elev);
  color: var(--fg-dim);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  padding: 6px 10px;
  font: 12px var(--sans);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: background 120ms, color 120ms, border-color 120ms;
}

.ghost:hover {
  color: var(--fg);
  border-color: var(--accent);
}

.ghost:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.ghost .icon {
  font-size: 13px;
}

.ghost.success {
  border-color: var(--ok);
  color: var(--ok);
}

/* ─────────── Status + footer ─────────── */

#status {
  margin: 0;
  padding: 10px 24px;
  color: var(--fg-muted);
  font-size: 13px;
  background: var(--panel-2);
  border-top: 1px solid var(--border);
}

#status[hidden] {
  display: none;
}

#status.error {
  color: var(--danger);
  background: color-mix(in srgb, var(--danger) 12%, var(--panel-2));
  border-top-color: color-mix(in srgb, var(--danger) 40%, var(--border));
}

.footer {
  border-top: 1px solid var(--border);
  background: var(--bg-elev);
}

.footer-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 8px;
  color: var(--fg-muted);
  font-size: 13px;
}

/* ─────────── Phone tuning ─────────── */

@media (max-width: 640px) {
  .topbar-inner {
    padding: 10px 14px;
  }

  .brand-tag {
    display: none;
  }

  .topbar-links a {
    padding: 4px 8px;
    font-size: 13px;
  }

  .hero-inner {
    padding: 22px 16px 18px;
  }

  .hero h1 {
    font-size: 1.45rem;
  }

  .hero p {
    font-size: 14px;
  }

  .panel {
    min-height: 0;
    border-radius: 8px;
  }

  .panel-head {
    padding: 10px 12px;
    flex-wrap: wrap;
    row-gap: 8px;
  }

  .panel-actions {
    flex-wrap: wrap;
  }

  .controls {
    padding: 10px 12px;
    gap: 10px;
  }

  .chips {
    width: 100%;
  }

  .chips legend {
    width: 100%;
    float: none;
    padding: 0 0 4px;
  }

  textarea {
    min-height: 220px;
    padding: 12px;
    font-size: 13px;
  }

  .tabs {
    padding: 8px 10px;
    min-height: 0;
  }

  .file-row {
    padding: 6px 10px;
    flex-wrap: wrap;
  }

  .filemeta {
    font-size: 11px;
    word-break: break-all;
  }

  #content {
    min-height: 200px;
    padding: 12px;
    font-size: 12.5px;
  }

  #status {
    padding: 10px 14px;
    font-size: 12.5px;
  }

  .footer-inner {
    padding: 12px 14px;
    flex-direction: column;
    align-items: flex-start;
    font-size: 12.5px;
  }
}