*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", sans-serif;
  background: #1a1a2e;
  color: #e8e8f0;
  line-height: 1.5;
  min-height: 100vh;
}

.app {
  max-width: 900px;
  margin: 0 auto;
  padding: 1.5rem 1rem 3rem;
}

header {
  text-align: center;
  margin-bottom: 1.5rem;
}

header h1 {
  margin: 0 0 0.25rem;
  font-size: 1.5rem;
  font-weight: 600;
}

.subtitle {
  margin: 0;
  color: #9898b0;
  font-size: 0.875rem;
}

.upload-section {
  text-align: center;
  margin-bottom: 1.5rem;
}

.file-btn {
  display: inline-block;
  padding: 0.6rem 1.25rem;
  background: #4f6ef7;
  color: #fff;
  border-radius: 8px;
  cursor: pointer;
  font-size: 0.95rem;
  transition: background 0.15s;
}

.file-btn:hover {
  background: #3d5ce0;
}

.file-info {
  display: block;
  margin-top: 0.5rem;
  font-size: 0.85rem;
  color: #9898b0;
}

.warning {
  color: #f0a050;
  font-size: 0.85rem;
  margin-top: 0.5rem;
}

.hidden {
  display: none !important;
}

.preview-section {
  margin-bottom: 1.5rem;
}

.cropper-wrap {
  position: relative;
  max-height: 70vh;
  background: #12121f;
  border-radius: 8px;
  overflow: hidden;
}

.cropper-wrap img {
  display: block;
  max-width: 100%;
}

.grid-overlay {
  position: absolute;
  pointer-events: none;
  z-index: 10;
  background-image:
    repeating-linear-gradient(
      to right,
      transparent,
      transparent calc(100% / 9 - 1px),
      rgba(79, 110, 247, 0.55) calc(100% / 9 - 1px),
      rgba(79, 110, 247, 0.55) calc(100% / 9)
    ),
    repeating-linear-gradient(
      to bottom,
      transparent,
      transparent calc(100% / 9 - 1px),
      rgba(79, 110, 247, 0.55) calc(100% / 9 - 1px),
      rgba(79, 110, 247, 0.55) calc(100% / 9)
    );
}

.checkbox-label {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  margin-top: 0.75rem;
  font-size: 0.9rem;
  cursor: pointer;
}

.checkbox-label.inline {
  display: inline-flex;
  margin-top: 0;
}

.controls fieldset {
  border: 1px solid #2e2e48;
  border-radius: 8px;
  padding: 1rem;
  margin-bottom: 1rem;
}

.controls legend {
  padding: 0 0.4rem;
  font-size: 0.85rem;
  color: #9898b0;
}

.radio-group {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

.radio-group label {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  cursor: pointer;
  font-size: 0.9rem;
}

.chroma-controls {
  margin-top: 0.75rem;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1rem;
}

.chroma-controls label {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.9rem;
}

.chroma-controls input[type="range"] {
  width: 120px;
}

.hint {
  font-size: 0.8rem;
  color: #f0a050;
}

.size-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1rem;
}

.size-row label {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.9rem;
}

.size-row input[type="number"] {
  width: 72px;
  padding: 0.35rem 0.5rem;
  border: 1px solid #2e2e48;
  border-radius: 6px;
  background: #12121f;
  color: #e8e8f0;
}

.preset-btns {
  margin-top: 0.75rem;
  display: flex;
  gap: 0.5rem;
}

.preset-btn {
  padding: 0.3rem 0.75rem;
  border: 1px solid #2e2e48;
  border-radius: 6px;
  background: #12121f;
  color: #e8e8f0;
  cursor: pointer;
  font-size: 0.85rem;
}

.preset-btn:hover {
  border-color: #4f6ef7;
}

.action-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 0.5rem;
}

.primary-btn,
.secondary-btn {
  padding: 0.6rem 1.1rem;
  border: none;
  border-radius: 8px;
  font-size: 0.9rem;
  cursor: pointer;
  transition: opacity 0.15s;
}

.primary-btn {
  background: #4f6ef7;
  color: #fff;
}

.secondary-btn {
  background: #2e2e48;
  color: #e8e8f0;
}

.primary-btn:hover,
.secondary-btn:hover {
  opacity: 0.9;
}

.primary-btn:disabled,
.secondary-btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.status {
  margin-top: 0.75rem;
  font-size: 0.85rem;
  color: #9898b0;
  min-height: 1.25rem;
}

.status.error {
  color: #f07070;
}

.status.success {
  color: #70d070;
}

.pick-mode .cropper-wrap {
  cursor: crosshair;
}