:root {
  color-scheme: dark;
  --bg: #09111f;
  --bg-soft: #0e192b;
  --panel: rgba(17, 29, 48, 0.9);
  --panel-strong: #142238;
  --border: #263852;
  --border-bright: #385372;
  --text: #f3f7fb;
  --muted: #91a4bc;
  --accent: #62e6bf;
  --accent-strong: #35cfa4;
  --accent-dark: #082f2b;
  --blue: #6cb6ff;
  --danger: #ff7d88;
  --warning: #ffc66d;
  --shadow: 0 24px 70px rgba(0, 0, 0, 0.28);
  font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-width: 320px;
  min-height: 100vh;
  color: var(--text);
  background:
    radial-gradient(circle at 85% 5%, rgba(57, 175, 169, 0.12), transparent 24rem),
    radial-gradient(circle at 10% 55%, rgba(57, 116, 192, 0.1), transparent 30rem),
    var(--bg);
}

button, select, textarea, input { font: inherit; }
button, select, summary, label { -webkit-tap-highlight-color: transparent; }

.site-header {
  height: 72px;
  padding: 0 clamp(20px, 4vw, 64px);
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid rgba(94, 124, 159, 0.25);
  background: rgba(7, 14, 26, 0.78);
  backdrop-filter: blur(18px);
}

.brand {
  display: flex;
  gap: 12px;
  align-items: center;
  color: inherit;
  text-decoration: none;
}

.brand-mark {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  border-radius: 10px;
  color: #05231f;
  background: linear-gradient(145deg, #86f2d2, #31b995);
  font-family: Georgia, serif;
  font-size: 23px;
  font-weight: 800;
  box-shadow: 0 7px 22px rgba(53, 207, 164, 0.2);
}

.brand strong, .brand small { display: block; }
.brand strong { letter-spacing: 0.08em; font-size: 14px; }
.brand small { margin-top: 1px; color: var(--muted); font-size: 12px; }

.header-actions {
  min-width: 0;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 14px;
}

.header-status {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--muted);
  font-size: 13px;
  white-space: nowrap;
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--warning);
  box-shadow: 0 0 0 4px rgba(255, 198, 109, 0.1);
}

.header-status.available .status-dot { background: var(--accent); box-shadow: 0 0 0 4px rgba(98, 230, 191, 0.1); }
.header-status.unavailable .status-dot { background: var(--danger); box-shadow: 0 0 0 4px rgba(255, 125, 136, 0.1); }

main { width: min(1560px, calc(100% - 40px)); margin: 0 auto; padding: 46px 0 64px; }

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.5fr) minmax(280px, 0.75fr);
  align-items: end;
  gap: 40px;
  margin-bottom: 34px;
}

.eyebrow, .panel-kicker {
  margin: 0 0 8px;
  color: var(--accent);
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

h1 { max-width: 850px; margin: 0; font-size: clamp(34px, 4vw, 64px); line-height: 1.02; letter-spacing: -0.045em; }
.hero-copy { margin: 0 0 5px; color: var(--muted); font-size: 16px; line-height: 1.65; }

.card {
  border: 1px solid var(--border);
  border-radius: 16px;
  background: linear-gradient(145deg, rgba(20, 34, 56, 0.9), rgba(13, 24, 41, 0.94));
  box-shadow: var(--shadow);
}

.toolbar {
  min-height: 102px;
  padding: 18px 20px;
  display: grid;
  grid-template-columns: 1fr 1fr 1.1fr;
  gap: 20px;
  align-items: center;
  margin-bottom: 20px;
}

.source-actions { display: flex; gap: 10px; flex-wrap: wrap; }
.button, select, .icon-button {
  min-height: 40px;
  border: 1px solid var(--border-bright);
  border-radius: 9px;
  color: var(--text);
  background: #17263b;
  cursor: pointer;
  transition: border-color 160ms ease, transform 160ms ease, background 160ms ease;
}

.button { padding: 0 17px; display: inline-flex; align-items: center; justify-content: center; gap: 8px; font-weight: 700; }
.button:hover, select:hover, .icon-button:hover:not(:disabled) { border-color: #5a7da3; }
.button:active, .icon-button:active { transform: translateY(1px); }
.button-primary { border-color: var(--accent-strong); color: #05231f; background: var(--accent); }
.button-primary:hover { border-color: #9effe1; background: #7cedca; }
.button-secondary { background: #17263b; }
.button:disabled { opacity: 0.55; cursor: wait; }
.spec-open-button { min-height: 34px; padding: 0 13px; font-size: 12px; white-space: nowrap; }

select { min-width: 190px; padding: 0 36px 0 12px; color: var(--text); }
.option-group { min-width: 0; margin: 0; padding: 0 0 0 20px; border: 0; border-left: 1px solid var(--border); }
.option-group legend, .option-label { display: block; margin-bottom: 9px; color: var(--muted); font-size: 11px; font-weight: 800; letter-spacing: 0.08em; text-transform: uppercase; }

.segmented-control { display: flex; padding: 4px; border: 1px solid var(--border); border-radius: 10px; background: #0c1727; }
.segmented-control label { flex: 1; cursor: pointer; }
.segmented-control input { position: absolute; opacity: 0; pointer-events: none; }
.segmented-control span { min-height: 36px; display: grid; place-items: center; border-radius: 7px; color: var(--muted); font-size: 13px; font-weight: 750; }
.segmented-control input:checked + span { color: var(--text); background: #20344e; box-shadow: 0 3px 12px rgba(0,0,0,0.2); }

.switch-row { display: flex; align-items: center; justify-content: space-between; gap: 18px; cursor: pointer; }
.switch-row.disabled { cursor: not-allowed; opacity: 0.55; }
.switch-row strong, .switch-row small { display: block; }
.switch-row strong { font-size: 14px; }
.switch-row small { margin-top: 3px; color: var(--muted); font-size: 12px; }
.switch-row input { position: absolute; opacity: 0; }
.switch { position: relative; flex: 0 0 auto; width: 46px; height: 26px; border-radius: 99px; background: #34445a; transition: 160ms ease; }
.switch::after { content: ""; position: absolute; width: 20px; height: 20px; top: 3px; left: 3px; border-radius: 50%; background: #d8e1ec; transition: 160ms ease; }
.switch-row input:checked + .switch { background: var(--accent-strong); }
.switch-row input:checked + .switch::after { transform: translateX(20px); background: white; }

.workspace { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 20px; }
.panel { min-width: 0; overflow: hidden; }
.panel-header { height: 78px; padding: 0 20px; display: flex; align-items: center; justify-content: space-between; border-bottom: 1px solid var(--border); }
.panel-header h2 { margin: 0; font-size: 19px; }
.panel-kicker { margin-bottom: 4px; }
.language-chip, .result-badge { padding: 5px 9px; border-radius: 6px; color: var(--blue); background: rgba(108, 182, 255, 0.1); font-size: 11px; font-weight: 800; letter-spacing: 0.06em; text-transform: uppercase; }

.editor-shell { height: 480px; display: grid; grid-template-columns: auto 1fr; overflow: hidden; background: #08111e; }
.line-numbers { min-width: 48px; height: 100%; margin: 0; padding: 19px 13px; overflow: hidden; border-right: 1px solid #1b2a3e; color: #4d6580; background: #0a1422; text-align: right; font: 14px/1.65 "SFMono-Regular", Consolas, monospace; user-select: none; }
#sourceEditor { width: 100%; height: 100%; resize: none; border: 0; outline: 0; padding: 18px; color: #d9e7f5; background: transparent; caret-color: var(--accent); font: 14px/1.65 "SFMono-Regular", Consolas, monospace; tab-size: 2; white-space: pre; overflow: auto; }

.stdin-panel { border-top: 1px solid var(--border); background: rgba(8, 17, 30, 0.64); }
.stdin-panel summary { padding: 12px 20px; color: var(--muted); cursor: pointer; font-size: 13px; font-weight: 700; }
.stdin-panel summary span { float: right; color: #5f7690; font-family: monospace; font-weight: 400; }
#stdinInput { width: 100%; height: 92px; resize: vertical; border: 0; border-top: 1px solid var(--border); outline: 0; padding: 13px 20px; color: var(--text); background: #091321; font: 13px/1.5 "SFMono-Regular", Consolas, monospace; }

.editor-actions { min-height: 72px; padding: 14px 20px; display: flex; justify-content: flex-end; gap: 10px; border-top: 1px solid var(--border); }
.play-icon { font-size: 10px; }

.results-panel { display: flex; min-height: 630px; flex-direction: column; }
.result-badge.neutral { color: var(--muted); background: rgba(145, 164, 188, 0.1); }
.result-badge.success { color: var(--accent); background: rgba(98, 230, 191, 0.1); }
.result-badge.failure { color: var(--danger); background: rgba(255, 125, 136, 0.1); }
.result-badge.running { color: var(--warning); background: rgba(255, 198, 109, 0.1); }

.tabs { height: 50px; padding: 0 18px; display: flex; gap: 22px; align-items: end; border-bottom: 1px solid var(--border); }
.tab { height: 50px; padding: 0 3px; border: 0; border-bottom: 2px solid transparent; color: var(--muted); background: transparent; cursor: pointer; font-size: 13px; font-weight: 750; }
.tab.active { border-bottom-color: var(--accent); color: var(--text); }
.result-toolbar { min-height: 46px; padding: 8px 18px; display: flex; align-items: center; justify-content: space-between; border-bottom: 1px solid rgba(38,56,82,0.65); color: var(--muted); font-size: 12px; }
.result-toolbar > div { display: flex; gap: 8px; }
.icon-button { min-height: 29px; padding: 0 10px; font-size: 11px; }
.icon-button:disabled { opacity: 0.38; cursor: default; }

.result-content { position: relative; flex: 1; min-height: 454px; background: #08111e; }
.result-content pre { position: absolute; inset: 0; margin: 0; padding: 20px; overflow: auto; color: #d9e7f5; font: 13px/1.6 "SFMono-Regular", Consolas, monospace; white-space: pre-wrap; word-break: break-word; }
.empty-state { min-height: 454px; padding: 40px; display: grid; place-content: center; justify-items: center; text-align: center; color: var(--muted); }
.empty-state[hidden], #resultView[hidden] { display: none; }
.empty-glyph { width: 56px; height: 56px; display: grid; place-items: center; margin-bottom: 15px; border: 1px solid var(--border); border-radius: 14px; color: var(--accent); background: rgba(98,230,191,0.06); font-family: monospace; font-weight: 800; }
.empty-state h3 { margin: 0 0 8px; color: #dce6f0; font-size: 16px; }
.empty-state p { max-width: 340px; margin: 0; font-size: 13px; line-height: 1.6; }

.interactive-input {
  min-height: 64px;
  padding: 12px 18px;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto auto;
  gap: 8px;
  align-items: center;
  border-top: 1px solid var(--border);
  background: #0a1422;
}
.interactive-input[hidden] { display: none; }
#interactiveInput {
  width: 100%;
  min-height: 40px;
  border: 1px solid var(--border-bright);
  border-radius: 8px;
  outline: 0;
  padding: 0 12px;
  color: var(--text);
  background: #091321;
  caret-color: var(--accent);
  font: 13px/1.4 "SFMono-Regular", Consolas, monospace;
}
#interactiveInput:focus { border-color: var(--accent-strong); }
.stop-run-button { border-color: rgba(255, 125, 136, 0.65); color: var(--danger); }

body.spec-open { overflow: hidden; }

.spec-dialog[hidden] { display: none; }
.spec-dialog {
  position: fixed;
  inset: 0;
  z-index: 20;
  display: grid;
  place-items: center;
  padding: 24px;
}

.spec-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(3, 8, 15, 0.72);
  backdrop-filter: blur(12px);
}

.spec-panel {
  position: relative;
  width: min(1120px, 100%);
  max-height: min(900px, calc(100vh - 48px));
  display: flex;
  flex-direction: column;
  overflow: hidden;
  border: 1px solid var(--border-bright);
  border-radius: 16px;
  background: linear-gradient(145deg, rgba(20, 34, 56, 0.98), rgba(8, 17, 30, 0.98));
  box-shadow: 0 30px 90px rgba(0, 0, 0, 0.45);
}

.spec-header {
  min-height: 78px;
  padding: 0 22px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  border-bottom: 1px solid var(--border);
}

.spec-header h2 { margin: 0; font-size: 20px; }

.spec-toolbar {
  min-height: 46px;
  padding: 8px 22px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  border-bottom: 1px solid rgba(38,56,82,0.65);
  color: var(--muted);
  font-size: 12px;
}

.spec-content {
  flex: 1;
  overflow: auto;
  padding: 26px 32px 36px;
  color: #dce7f3;
  background: #08111e;
  line-height: 1.7;
}

.spec-content h2,
.spec-content h3,
.spec-content h4,
.spec-content h5 {
  margin: 32px 0 12px;
  color: var(--text);
  line-height: 1.22;
}

.spec-content h2:first-child { margin-top: 0; }
.spec-content h2 { font-size: 25px; }
.spec-content h3 { font-size: 20px; }
.spec-content h4 { font-size: 16px; color: #e7eef7; }
.spec-content h5 { font-size: 14px; color: #cfdceb; }
.spec-content p { margin: 0 0 14px; }
.spec-content ul,
.spec-content ol { margin: 0 0 18px 22px; padding: 0; }
.spec-content li { margin: 6px 0; }

.spec-content code {
  padding: 2px 5px;
  border-radius: 5px;
  color: #a9f6dc;
  background: rgba(98, 230, 191, 0.08);
  font: 0.92em "SFMono-Regular", Consolas, monospace;
}

.spec-content pre {
  margin: 14px 0 20px;
  padding: 16px;
  overflow: auto;
  border: 1px solid #1b2a3e;
  border-radius: 10px;
  background: #050b14;
}

.spec-content pre code {
  padding: 0;
  color: #d9e7f5;
  background: transparent;
  font-size: 13px;
  line-height: 1.6;
}

.spec-table-wrap { margin: 14px 0 20px; overflow-x: auto; }
.spec-content table {
  width: 100%;
  min-width: 620px;
  border-collapse: collapse;
  font-size: 13px;
}

.spec-content th,
.spec-content td {
  padding: 10px 12px;
  border: 1px solid #1f3148;
  text-align: left;
  vertical-align: top;
}

.spec-content th {
  color: var(--text);
  background: #102036;
}

.spec-content td { background: rgba(16, 32, 54, 0.42); }
.spec-loading, .spec-error { margin: 0; color: var(--muted); }
.spec-error { color: var(--danger); }

.toast { position: fixed; left: 50%; bottom: 24px; z-index: 10; padding: 10px 16px; border: 1px solid var(--border-bright); border-radius: 9px; color: var(--text); background: #17263b; box-shadow: var(--shadow); font-size: 13px; opacity: 0; pointer-events: none; transform: translate(-50%, 10px); transition: 180ms ease; }
.toast.show { opacity: 1; transform: translate(-50%, 0); }
.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; }

@media (max-width: 1050px) {
  .hero { grid-template-columns: 1fr; gap: 18px; }
  .toolbar { grid-template-columns: 1fr 1fr; }
  .optimisation-option { grid-column: 1 / -1; }
  .workspace { grid-template-columns: 1fr; }
}

@media (max-width: 640px) {
  .site-header { padding: 0 16px; }
  .header-actions { gap: 10px; }
  .header-status span:last-child { display: none; }
  .spec-open-button { min-height: 32px; padding: 0 10px; }
  main { width: min(100% - 24px, 1560px); padding-top: 30px; }
  .toolbar { grid-template-columns: 1fr; }
  .option-group { padding: 15px 0 0; border-left: 0; border-top: 1px solid var(--border); }
  .optimisation-option { grid-column: auto; }
  .source-actions > * { flex: 1; }
  select { width: 100%; min-width: 0; }
  .editor-shell { height: 420px; }
  .editor-actions { flex-direction: column-reverse; }
  .editor-actions .button { width: 100%; }
  .interactive-input { grid-template-columns: 1fr; }
  .interactive-input .button, .interactive-input .icon-button { width: 100%; }
  .result-toolbar { align-items: flex-start; gap: 10px; flex-direction: column; }
  .results-panel { min-height: 600px; }
  .spec-dialog { padding: 10px; }
  .spec-panel { max-height: calc(100vh - 20px); border-radius: 12px; }
  .spec-header { min-height: auto; padding: 16px; align-items: flex-start; }
  .spec-header h2 { font-size: 18px; }
  .spec-toolbar { padding: 12px 16px; align-items: flex-start; flex-direction: column; }
  .spec-content { padding: 18px; }
  .spec-content h2 { font-size: 22px; }
  .spec-content table { min-width: 560px; }
}