:root {
  color-scheme: light;
  font-family: "Microsoft YaHei", "PingFang SC", "Helvetica Neue", Arial, sans-serif;
  background: #f4f5f7;
  color: #1f2933;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
}

.app {
  display: grid;
  grid-template-columns: minmax(280px, 360px) 1fr;
  min-height: 100vh;
}

.panel {
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: 20px;
  background: #ffffff;
  border-right: 1px solid #dde2ea;
  overflow-y: auto;
}

.group {
  display: grid;
  gap: 12px;
}

h1,
h2 {
  margin: 0;
  line-height: 1.25;
}

h1 {
  font-size: 20px;
}

h2 {
  font-size: 16px;
}

label {
  display: grid;
  gap: 6px;
  font-size: 13px;
  color: #52606d;
}

input[type="text"],
input[type="number"],
select {
  width: 100%;
  height: 38px;
  border: 1px solid #cbd2d9;
  border-radius: 6px;
  padding: 0 10px;
  font: inherit;
  color: #1f2933;
  background: #ffffff;
}

input[type="color"] {
  width: 100%;
  height: 38px;
  border: 1px solid #cbd2d9;
  border-radius: 6px;
  background: #ffffff;
  padding: 3px;
}

.file-button,
button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  border: 1px solid #cbd2d9;
  border-radius: 6px;
  padding: 0 14px;
  font: inherit;
  font-weight: 700;
  color: #243b53;
  background: #ffffff;
  cursor: pointer;
  user-select: none;
}

.file-button.primary,
.export {
  border-color: #f25a21;
  color: #ffffff;
  background: #f25a21;
}

.file-button input {
  display: none;
}

.button-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.form-grid {
  display: grid;
  gap: 12px;
}

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

.status {
  min-height: 38px;
  margin: 0;
  padding: 10px 12px;
  border-radius: 6px;
  background: #f5f7fa;
  font-size: 13px;
  line-height: 1.45;
  color: #52606d;
}

.preview-wrap {
  min-width: 0;
  padding: 24px;
  overflow: auto;
  background: #e9edf3;
}

.canvas-shell {
  width: min(100%, 540px);
  margin: 0 auto;
  transition: width 0.2s ease;
}

.canvas-shell[data-layout="landscape"] {
  width: min(100%, 960px);
}

.canvas-shell[data-layout="adaptive"] {
  width: min(100%, 960px);
}

#posterCanvas {
  display: block;
  width: 100%;
  height: auto;
  border-radius: 8px;
  box-shadow: 0 16px 48px rgba(31, 41, 51, 0.18);
  background: #ffffff;
  touch-action: none;
}

@media (max-width: 900px) {
  .app {
    grid-template-columns: 1fr;
  }

  .panel {
    border-right: 0;
    border-bottom: 1px solid #dde2ea;
  }

  .preview-wrap {
    padding: 16px;
  }
}