:root {
  --bg: #1b1916;
  --panel: #25221d;
  --panel-2: #2d2922;
  --border: #3a352d;
  --text: #e9e3d6;
  --muted: #a89e8b;
  --accent: #cfa86a;       /* warm possum tan */
  --accent-2: #d98fa0;     /* pink nose */
  --ok: #9cc47e;
  --err: #e08a78;
  --mono: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, monospace;
  --sans: system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
}

* { box-sizing: border-box; }

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

body {
  background: radial-gradient(120% 120% at 80% -10%, #2a261f 0%, var(--bg) 55%);
  color: var(--text);
  font-family: var(--sans);
  font-size: 15px;
}

.wrap {
  height: 100vh;
  display: grid;
  grid-template-rows: auto 1fr;
  padding: 1rem;
  gap: 1rem;
}

/* ---- top bar ---- */
.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}
.brand { display: flex; align-items: center; gap: 0.75rem; }
.brand-icon {
  font-size: 2.2rem;
  filter: drop-shadow(0 2px 4px rgba(0,0,0,0.4));
}
.brand-text h1 {
  margin: 0;
  font-size: 1.5rem;
  letter-spacing: 0.5px;
  color: var(--accent);
}
.brand-text p {
  margin: 0.1rem 0 0;
  font-size: 0.82rem;
  color: var(--muted);
}

.toolbar { display: flex; align-items: center; gap: 0.6rem; flex-wrap: wrap; }
.ex-label { display: flex; flex-direction: column; font-size: 0.65rem; color: var(--muted); text-transform: uppercase; letter-spacing: 0.08em; gap: 2px; }
.ex-label select {
  background: var(--panel-2);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 7px;
  padding: 0.4rem 0.5rem;
  font-family: var(--sans);
  font-size: 0.85rem;
  cursor: pointer;
}
.btn {
  background: var(--panel-2);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 7px;
  padding: 0.55rem 0.95rem;
  font-size: 0.9rem;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s, transform 0.05s;
}
.btn:hover { background: #38332b; border-color: #4a4439; }
.btn:active { transform: translateY(1px); }
.btn-run {
  background: linear-gradient(180deg, #d9b277, var(--accent));
  color: #2a2114;
  font-weight: 600;
  border-color: #b9904f;
}
.btn-run:hover { background: linear-gradient(180deg, #e4bd82, #d6af72); }

/* ---- main layout ---- */
.main {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  min-height: 0;
}
.right {
  display: grid;
  grid-template-rows: minmax(0, 1.1fr) minmax(0, 1fr);
  gap: 1rem;
  min-height: 0;
}

.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 11px;
  display: flex;
  flex-direction: column;
  min-height: 0;
  overflow: hidden;
}
.panel-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.55rem 0.85rem;
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.09em;
  color: var(--muted);
  border-bottom: 1px solid var(--border);
  background: rgba(0,0,0,0.12);
}
.panel-head .hint { text-transform: none; letter-spacing: 0; font-size: 0.72rem; opacity: 0.7; }

/* ---- editor ---- */
.editor-panel textarea {
  flex: 1;
  min-height: 0;
  resize: none;
  border: none;
  outline: none;
  background: transparent;
  color: var(--text);
  font-family: var(--mono);
  font-size: 0.92rem;
  line-height: 1.55;
  padding: 0.85rem 1rem;
  tab-size: 2;
}
.editor-panel textarea::selection { background: rgba(207,168,106,0.32); }

/* ---- output ---- */
.output-panel { min-height: 0; }
.output {
  flex: 1;
  min-height: 0;
  margin: 0;
  padding: 0.85rem 1rem;
  overflow: auto;
  font-family: var(--mono);
  font-size: 0.92rem;
  line-height: 1.5;
  white-space: pre-wrap;
  word-break: break-word;
  color: #d7e8c8;
}
.output-error { color: var(--err); }

.status { text-transform: none; letter-spacing: 0; }
.status-ok { color: var(--ok); }
.status-err { color: var(--err); }

.stackview {
  border-top: 1px solid var(--border);
  padding: 0.5rem 0.85rem;
  font-family: var(--mono);
  font-size: 0.82rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
  flex-wrap: wrap;
  background: rgba(0,0,0,0.14);
  max-height: 30%;
  overflow: auto;
}
.sv-label { color: var(--muted); text-transform: uppercase; letter-spacing: 0.08em; font-size: 0.66rem; }
.sv-empty { color: var(--muted); font-style: italic; }
.sv-item {
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 5px;
  padding: 0.1rem 0.45rem;
  color: var(--accent);
}

/* ---- reference ---- */
.ref-panel { min-height: 0; }
.ref {
  overflow: auto;
  padding: 0.4rem 1rem 1rem;
  font-size: 0.85rem;
  line-height: 1.5;
}
.ref-intro { color: var(--muted); }
.ref h3 {
  margin: 1rem 0 0.35rem;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--accent-2);
}
.ref ul { margin: 0; padding-left: 1.1rem; }
.ref li { margin: 0.18rem 0; }
.ref code {
  font-family: var(--mono);
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 0.05rem 0.32rem;
  font-size: 0.82rem;
  color: var(--accent);
}

@media (max-width: 820px) {
  body { font-size: 14px; }
  .main { grid-template-columns: 1fr; grid-template-rows: 1fr 1fr; }
}