:root {
  --bg: #f4efe6;
  --panel: rgba(255, 250, 242, 0.84);
  --panel-strong: #fffdf9;
  --line: rgba(41, 37, 36, 0.12);
  --text: #1f1b17;
  --muted: #6f655d;
  --accent: #b5512d;
  --accent-deep: #8f3f24;
  --shadow: 0 30px 80px rgba(54, 38, 19, 0.12);
  --radius-lg: 28px;
  --radius-md: 18px;
  --radius-sm: 12px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Avenir Next", "Segoe UI", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top left, rgba(223, 188, 132, 0.28), transparent 32%),
    linear-gradient(135deg, #f5efe4 0%, #efe7da 48%, #f8f5f0 100%);
}

button,
select,
input {
  font: inherit;
}

.app-shell {
  display: grid;
  grid-template-columns: minmax(320px, 380px) minmax(0, 1fr);
  gap: 24px;
  padding: 24px;
  min-height: 100vh;
}

.control-panel,
.preview-panel {
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: var(--panel);
  box-shadow: var(--shadow);
  backdrop-filter: blur(16px);
}

.control-panel {
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.panel-header h1,
.preview-header h2 {
  margin: 0;
  font-family: Georgia, "Times New Roman", serif;
  font-weight: 700;
}

.panel-header h1 {
  font-size: clamp(2rem, 4vw, 2.6rem);
  line-height: 1;
  margin-top: 8px;
}

.preview-header h2 {
  font-size: 1.5rem;
}

.eyebrow {
  margin: 0;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.16em;
  font-size: 0.72rem;
  font-weight: 700;
}

.intro,
.template-description,
.preview-meta,
.dropzone-copy span {
  margin: 0;
  color: var(--muted);
  line-height: 1.5;
}

.control-group {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.control-grid {
  display: grid;
  gap: 16px;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.group-label {
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.dropzone {
  position: relative;
  min-height: 180px;
  border: 1.5px dashed rgba(181, 81, 45, 0.4);
  border-radius: var(--radius-md);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.7), rgba(255, 249, 242, 0.95));
  display: grid;
  place-items: center;
  cursor: pointer;
  overflow: hidden;
  transition: transform 180ms ease, border-color 180ms ease;
}

.dropzone.is-dragging {
  transform: translateY(-2px);
  border-color: var(--accent);
}

.dropzone-copy {
  text-align: center;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.dropzone-copy strong {
  font-size: 1.05rem;
}

.cover-thumb {
  position: absolute;
  inset: 12px;
  width: calc(100% - 24px);
  height: calc(100% - 24px);
  object-fit: contain;
  border-radius: var(--radius-sm);
  box-shadow: 0 22px 42px rgba(0, 0, 0, 0.16);
  background: #fff;
}

.hidden {
  display: none;
}

select,
input[type="text"],
input[type="range"] {
  width: 100%;
}

select,
input[type="text"] {
  appearance: none;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: var(--panel-strong);
  padding: 12px 16px;
  color: var(--text);
}

input[type="text"]::placeholder {
  color: #9b9188;
}

input[type="range"] {
  accent-color: var(--accent);
}

.primary-button {
  border: 0;
  border-radius: 999px;
  padding: 14px 18px;
  background: linear-gradient(135deg, var(--accent), var(--accent-deep));
  color: white;
  font-weight: 700;
  cursor: pointer;
  box-shadow: 0 20px 40px rgba(181, 81, 45, 0.28);
}

.primary-button:hover {
  filter: brightness(1.04);
}

.preview-panel {
  padding: 20px;
  display: flex;
  flex-direction: column;
  min-height: 0;
}

.preview-header {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: end;
  padding-bottom: 16px;
}

.preview-stage {
  position: relative;
  flex: 1;
  min-height: 460px;
  border-radius: calc(var(--radius-lg) - 8px);
  overflow: hidden;
  background: rgba(255, 255, 255, 0.6);
  border: 1px solid rgba(41, 37, 36, 0.08);
}

#preview-canvas {
  width: 100%;
  height: 100%;
  display: block;
}

.preview-overlay {
  position: absolute;
  left: 16px;
  bottom: 16px;
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.preview-overlay span {
  border-radius: 999px;
  padding: 8px 12px;
  background: rgba(255, 255, 255, 0.82);
  border: 1px solid rgba(41, 37, 36, 0.08);
  font-size: 0.82rem;
}

@media (max-width: 980px) {
  .app-shell {
    grid-template-columns: 1fr;
  }

  .preview-stage {
    min-height: 55vh;
  }
}

@media (max-width: 640px) {
  .app-shell {
    padding: 14px;
    gap: 14px;
  }

  .control-panel,
  .preview-panel {
    border-radius: 20px;
  }

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

  .preview-header {
    flex-direction: column;
    align-items: start;
  }
}