:root {
  --bg: #f5f6f8;
  --card: #ffffff;
  --text: #1f2328;
  --muted: #6b7280;
  --border: #e5e7eb;
  --primary: #2563eb;
  --primaryHover: #1d4ed8;
  --radius: 12px;
  --panelWidth: 420px;
  --previewWidth: 820px;
  --containerMax: 1296px;
}

* {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei",
    "Noto Sans CJK SC", Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
}

.topbar {
  height: 56px;
  display: grid;
  place-items: center;
  border-bottom: 1px solid var(--border);
  background: #fff;
}

.topbar__inner {
  width: 100%;
  max-width: var(--containerMax);
  padding: 0 18px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand__title {
  font-size: 20px;
  font-weight: 700;
}

.topbar__link {
  font-size: 14px;
  color: var(--primary);
  text-decoration: none;
}

.layout {
  padding: 18px;
  display: grid;
  grid-template-columns: var(--panelWidth) var(--previewWidth);
  gap: 18px;
  align-items: start;
  width: 100%;
  max-width: var(--containerMax);
  margin: 0 auto;
}

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

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

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px;
}

.card__title {
  font-weight: 700;
  margin-bottom: 10px;
}

.upload {
  display: grid;
  gap: 10px;
  justify-items: center;
  padding: 18px 6px;
  border-radius: 10px;
  background: #fafafa;
  border: 1px dashed var(--border);
}

.upload__input {
  display: none;
}

.muted {
  color: var(--muted);
  font-size: 12px;
}

.grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

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

.field {
  display: grid;
  gap: 8px;
}

.field__label {
  font-size: 12px;
  color: #374151;
}

.field__control {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: 10px;
}

.unit {
  font-size: 12px;
  color: var(--muted);
}

.input,
.select,
.textarea {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 10px;
  outline: none;
  font-size: 14px;
  background: #fff;
}

.textarea {
  resize: vertical;
  min-height: 120px;
  line-height: 1.5;
}

.input:focus,
.select:focus,
.textarea:focus {
  border-color: #93c5fd;
  box-shadow: 0 0 0 4px rgba(147, 197, 253, 0.35);
}

.color {
  display: grid;
  grid-template-columns: 44px 1fr;
  gap: 10px;
  align-items: center;
}

.color__pick {
  width: 44px;
  height: 40px;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: #fff;
}

.actions {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.btn {
  height: 44px;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: #fff;
  cursor: pointer;
  font-size: 14px;
}

.btn:disabled {
  cursor: not-allowed;
  opacity: 0.6;
}

.btn--primary {
  border-color: transparent;
  background: var(--primary);
  color: #fff;
}

.btn--primary:hover {
  background: var(--primaryHover);
}

.status {
  min-height: 18px;
  font-size: 12px;
  color: var(--muted);
}

.preview {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px;
}

.preview__title {
  font-weight: 700;
  margin-bottom: 10px;
}

.preview__frame {
  background: #f3f4f6;
  border-radius: 12px;
  padding: 16px;
  min-height: 540px;
  display: grid;
  place-items: center;
  overflow: auto;
}

.canvas {
  max-width: 100%;
  height: auto;
  background: transparent;
}