:root {
  color-scheme: light;
  --bg: #f6f3ec;
  --surface: #fffdf8;
  --surface-strong: #ffffff;
  --ink: #20201d;
  --muted: #66645e;
  --line: #ded8ca;
  --accent: #0f766e;
  --accent-dark: #0a5f59;
  --accent-soft: #d8efea;
  --danger: #a33b32;
  --shadow: 0 22px 70px rgba(48, 43, 31, 0.13);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  min-height: 100vh;
  margin: 0;
  background:
    linear-gradient(135deg, rgba(15, 118, 110, 0.12), transparent 34%),
    linear-gradient(315deg, rgba(194, 80, 58, 0.09), transparent 30%),
    var(--bg);
  color: var(--ink);
}

button,
textarea {
  font: inherit;
}

.app-shell {
  width: min(1120px, calc(100% - 32px));
  min-height: 100vh;
  margin: 0 auto;
  padding: 48px 0;
  display: grid;
  place-items: center;
}

.workspace {
  width: 100%;
  display: grid;
  grid-template-columns: minmax(280px, 0.9fr) minmax(320px, 1.1fr);
  gap: 20px;
  align-items: stretch;
}

.intro,
.tool-panel,
.preview-panel {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 253, 248, 0.9);
  box-shadow: var(--shadow);
}

.site-banner {
  grid-column: 1 / -1;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface-strong);
  box-shadow: var(--shadow);
  padding: 14px 18px;
  color: var(--accent-dark);
  font-size: clamp(1.25rem, 2vw, 1.7rem);
  font-weight: 900;
  text-align: center;
}

.intro {
  grid-column: 1 / -1;
  padding: 26px 28px;
  display: grid;
  gap: 8px;
}

.eyebrow {
  margin: 0;
  color: var(--accent-dark);
  font-size: 0.8rem;
  font-weight: 800;
  text-transform: uppercase;
}

h1 {
  margin: 0;
  font-size: clamp(2rem, 2.7vw, 3.4rem);
  line-height: 1;
  letter-spacing: 0;
}

.summary {
  max-width: 66ch;
  margin: 0;
  color: var(--muted);
  line-height: 1.55;
}

.tool-panel,
.preview-panel {
  min-height: 480px;
  padding: 24px;
}

.tool-panel {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

label {
  font-weight: 750;
}

textarea {
  width: 100%;
  min-height: 174px;
  resize: vertical;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface-strong);
  color: var(--ink);
  padding: 14px 16px;
  line-height: 1.45;
  outline: none;
  box-shadow: inset 0 1px 0 rgba(32, 32, 29, 0.04);
}

textarea:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 4px var(--accent-soft);
}

.input-meta,
.qr-details {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: space-between;
  color: var(--muted);
  font-size: 0.9rem;
}

.controls {
  display: grid;
  grid-template-columns: 1fr 0.7fr 1fr;
  gap: 10px;
  margin-top: 4px;
}

button {
  min-height: 44px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface-strong);
  color: var(--ink);
  padding: 0 14px;
  font-weight: 760;
  cursor: pointer;
  transition: transform 160ms ease, border-color 160ms ease, background 160ms ease, color 160ms ease;
}

button:hover:not(:disabled) {
  transform: translateY(-1px);
  border-color: #bfb6a5;
}

button:focus-visible {
  outline: 3px solid var(--accent-soft);
  outline-offset: 2px;
}

button.primary {
  border-color: var(--accent-dark);
  background: var(--accent);
  color: #ffffff;
}

button.primary:hover:not(:disabled) {
  background: var(--accent-dark);
}

button:disabled {
  cursor: not-allowed;
  opacity: 0.54;
}

.message {
  min-height: 44px;
  margin: auto 0 0;
  border-left: 3px solid var(--accent);
  background: rgba(216, 239, 234, 0.68);
  border-radius: 6px;
  padding: 11px 12px;
  color: var(--accent-dark);
  line-height: 1.35;
}

.message.error {
  border-left-color: var(--danger);
  background: #fae6df;
  color: var(--danger);
}

.preview-panel {
  display: grid;
  grid-template-rows: minmax(320px, 1fr) auto;
  gap: 16px;
}

.preview-surface {
  position: relative;
  display: grid;
  place-items: center;
  min-height: 320px;
  border: 1px dashed #c8beaa;
  border-radius: 8px;
  background:
    linear-gradient(90deg, rgba(32, 32, 29, 0.035) 1px, transparent 1px),
    linear-gradient(0deg, rgba(32, 32, 29, 0.035) 1px, transparent 1px),
    #fffefa;
  background-size: 24px 24px;
  padding: 18px;
  overflow: hidden;
}

canvas {
  display: none;
  width: min(100%, 420px);
  max-height: 420px;
  aspect-ratio: 1;
  border-radius: 8px;
  background: #ffffff;
  box-shadow: 0 18px 42px rgba(32, 32, 29, 0.16);
}

.preview-surface.has-code canvas {
  display: block;
}

.empty-state {
  position: absolute;
  inset: 18px;
  display: grid;
  place-items: center;
  align-content: center;
  gap: 12px;
  color: var(--muted);
  text-align: center;
}

.preview-surface.has-code .empty-state {
  display: none;
}

.empty-mark {
  width: 96px;
  height: 96px;
  display: grid;
  place-items: center;
  border: 10px solid var(--accent-soft);
  border-radius: 8px;
  color: var(--accent-dark);
  font-weight: 900;
}

.empty-state p {
  margin: 0;
}

.qr-details {
  border-top: 1px solid var(--line);
  padding-top: 14px;
}

@media (max-width: 820px) {
  .app-shell {
    width: min(100% - 22px, 620px);
    padding: 24px 0;
    align-items: start;
  }

  .workspace {
    grid-template-columns: 1fr;
    gap: 14px;
  }

  .intro,
  .tool-panel,
  .preview-panel {
    padding: 18px;
  }

  .tool-panel,
  .preview-panel {
    min-height: auto;
  }

  .controls {
    grid-template-columns: 1fr;
  }

  .preview-panel {
    grid-template-rows: minmax(280px, auto) auto;
  }
}