/* ================================
   Reset & 全局规则
================================ */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
[hidden] { display: none !important; }

:root {
  --bg: #0f0f11;
  --surface: #18181c;
  --surface-2: #222228;
  --surface-3: #2c2c35;
  --border: #313139;
  --border-light: #3e3e4a;
  --text-primary: #f0f0f2;
  --text-secondary: #9898a8;
  --text-muted: #5a5a6a;
  --accent: #7c6bff;
  --accent-hover: #9183ff;
  --accent-dim: rgba(124,107,255,0.15);
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --shadow-lg: 0 8px 40px rgba(0,0,0,0.5);
  --transition: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --font: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
}

html { scroll-behavior: smooth; }
body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex; flex-direction: column;
  -webkit-font-smoothing: antialiased;
}

/* ================================
   Header
================================ */
.header {
  border-bottom: 1px solid var(--border);
  background: rgba(15,15,17,0.85);
  backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px);
  position: sticky; top: 0; z-index: 100;
}
.header-inner {
  max-width: 1400px; margin: 0 auto;
  padding: 14px 24px;
  display: flex; align-items: center; gap: 20px;
}
.logo { display: flex; align-items: center; gap: 8px; }
.logo-icon { font-size: 20px; filter: drop-shadow(0 0 8px rgba(124,107,255,0.6)); }
.logo-text {
  font-size: 18px; font-weight: 600;
  background: linear-gradient(135deg, #c4bbff, #7c6bff);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
  letter-spacing: -0.3px;
}
.header-sub { font-size: 13px; color: var(--text-muted); padding-left: 20px; border-left: 1px solid var(--border); }
.flex-1 { flex: 1; }

.batch-actions { display: flex; gap: 10px; }
.btn-secondary {
  background: var(--surface-2); color: var(--text-secondary);
  border: 1px solid var(--border); border-radius: var(--radius-sm);
  padding: 6px 14px; font-size: 12px; font-weight: 500; cursor: pointer;
  transition: all var(--transition);
}
.btn-secondary:hover { background: var(--surface-3); color: var(--text-primary); border-color: var(--accent); }

/* ================================
   Main Layout
================================ */
.main { flex: 1; max-width: 1400px; margin: 0 auto; width: 100%; padding: 32px 24px; }
.workspace { display: grid; grid-template-columns: 1fr 340px; gap: 24px; align-items: start; }

/* ================================
   预览面板
================================ */
.preview-panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-xl);
  overflow: hidden;
  min-height: 540px;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  position: sticky;
  top: 80px; /* 留出 header 高度的距离 */
  z-index: 40;
}

.upload-zone {
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  gap: 12px; padding: 60px 40px;
  width: 100%; min-height: 540px;
  border: 2px dashed var(--border-light);
  border-radius: var(--radius-xl);
  cursor: pointer;
  transition: border-color var(--transition), background var(--transition);
}
.upload-zone:hover, .upload-zone.drag-over {
  border-color: var(--accent); background: var(--accent-dim);
}
.upload-icon { font-size: 52px; line-height: 1; margin-bottom: 8px; }
.upload-title { font-size: 18px; font-weight: 500; }
.upload-hint { font-size: 13px; color: var(--text-muted); margin-bottom: 15px; }

.btn-upload {
  background: var(--accent); color: #fff; border: none;
  border-radius: var(--radius-md); padding: 12px 32px;
  font-size: 14px; font-weight: 500; cursor: pointer; font-family: var(--font);
  transition: background var(--transition), transform var(--transition), box-shadow var(--transition);
}
.btn-upload:hover { background: var(--accent-hover); transform: translateY(-1px); box-shadow: 0 4px 16px rgba(124,107,255,0.4); }

.canvas-wrap {
  width: 100%; height: 100%; border-radius: var(--radius-xl);
  display: flex; flex-direction: column; align-items: center; justify-content: space-between;
  padding: 30px 24px 20px; position: relative;
}
.canvas-wrap canvas {
  box-shadow: var(--shadow-lg); display: block;
  cursor: grab;
}

.btn-reupload {
  position: absolute; top: 20px; right: 20px;
  background: rgba(0,0,0,0.5); backdrop-filter: blur(8px);
  color: #fff; border: 1px solid rgba(255,255,255,0.15);
  border-radius: var(--radius-sm); padding: 6px 14px;
  font-size: 12px; cursor: pointer; transition: background var(--transition);
}
.btn-reupload:hover { background: rgba(0,0,0,0.75); }

/* ================================
   缩略图条
================================ */
.thumbnail-outer { width: 100%; padding-top: 20px; margin-top: auto; border-top: 1px solid var(--border); overflow: hidden; }
.thumbnail-strip {
  display: flex; gap: 10px; overflow-x: auto; padding: 4px 10px 10px;
  scrollbar-width: thin; scrollbar-color: var(--border) transparent;
}
.thumbnail-strip::-webkit-scrollbar { height: 4px; }
.thumbnail-strip::-webkit-scrollbar-thumb { background: var(--border); border-radius: 4px; }

.thumb-item {
  width: 60px; height: 60px; border-radius: var(--radius-sm);
  background: var(--surface-2); border: 2px solid transparent;
  cursor: pointer; overflow: hidden; flex-shrink: 0;
  transition: all var(--transition);
  position: relative;
}
.thumb-item img { width: 100%; height: 100%; object-fit: cover; }
.thumb-item:hover { transform: scale(1.05); border-color: var(--border-light); }
.thumb-item.active { border-color: var(--accent); box-shadow: 0 0 12px rgba(124,107,255,0.4); }

/* ================================
   控制面板
================================ */
.control-panel { display: flex; flex-direction: column; gap: 12px; }
.panel-section {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: 18px 20px;
  animation: fadeIn 0.3s ease both;
}
.panel-title {
  font-size: 11px; font-weight: 600; color: var(--text-muted);
  text-transform: uppercase; letter-spacing: 0.08em; margin-bottom: 14px;
}

/* ================================
   内容样式
================================ */
.ratio-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 6px; }
.ratio-item {
  background: var(--surface-2); color: var(--text-secondary);
  border: 1px solid var(--border); border-radius: var(--radius-sm);
  padding: 7px 4px; font-size: 11px; font-weight: 500;
  cursor: pointer; transition: all var(--transition); text-align: center;
}
.ratio-item:hover { border-color: var(--accent); color: var(--text-primary); }
.ratio-item.active { border-color: var(--accent); background: var(--accent-dim); color: var(--accent); }

.custom-ratio-row {
  display: flex; align-items: center; gap: 8px;
  margin-top: 10px; padding: 8px 10px;
  background: var(--surface-2); border-radius: var(--radius-sm);
  border: 1px solid var(--border);
}
.ratio-input {
  width: 42px; padding: 4px 6px; text-align: center;
  background: var(--surface-3); color: var(--text-primary);
  border: 1px solid var(--border); border-radius: 6px;
  font-size: 13px; font-family: var(--font);
  -moz-appearance: textfield;
}
.ratio-input::-webkit-inner-spin-button,
.ratio-input::-webkit-outer-spin-button { -webkit-appearance: none; margin: 0; }
.ratio-input:focus { border-color: var(--accent); outline: none; }
.ratio-sep { color: var(--text-muted); font-size: 13px; font-weight: 600; }
.ratio-apply-btn {
  margin-left: auto; padding: 4px 12px;
  background: var(--accent); color: #fff; border: none;
  border-radius: 6px; font-size: 11px; font-weight: 500;
  cursor: pointer; transition: background var(--transition);
}
.ratio-apply-btn:hover { background: var(--accent-hover); }

.frame-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 8px; }
.frame-item {
  display: flex; flex-direction: column; align-items: center; gap: 6px;
  background: transparent; border: 2px solid transparent;
  border-radius: var(--radius-md); padding: 8px 4px;
  cursor: pointer; transition: all var(--transition);
}
.frame-item:hover { background: var(--surface-2); transform: translateY(-1px); }
.frame-item.active { border-color: var(--accent); background: var(--accent-dim); }
.frame-item span { font-size: 10px; color: var(--text-secondary); text-align: center; }
.frame-item.active span { color: var(--accent); }

.frame-thumb { width: 52px; height: 42px; border-radius: 6px; display: flex; align-items: center; justify-content: center; overflow: hidden; flex-shrink: 0; }
.frame-thumb-inner { width: 100%; height: 100%; }

.frame-thumb--white { background: #fff; padding: 4px; }
.frame-thumb--white .frame-thumb-inner { background: linear-gradient(135deg,#bbb,#888); border-radius: 1px; }
.frame-thumb--black { background: #1a1a1a; padding: 4px; border: 1px solid #333; }
.frame-thumb--black .frame-thumb-inner { background: linear-gradient(135deg,#bbb,#888); border-radius: 1px; }
.frame-thumb--museum { background: #fff; padding: 0px; border: 4px solid #fff; box-shadow: inset 0 0 4px rgba(0,0,0,0.2), 0 2px 4px rgba(0,0,0,0.1); }
.frame-thumb--museum .frame-thumb-inner { background: linear-gradient(135deg,#bbb,#888); }
.frame-thumb--gallery { background: #111; padding: 2px; border: 1px solid #333; }
.frame-thumb--gallery .frame-thumb-inner { background: #f5f2ed; display: flex; align-items: center; justify-content: center; }
.frame-thumb--gallery .frame-thumb-inner::after { content: ''; display: block; width: 70%; height: 70%; background: linear-gradient(135deg,#bbb,#888); }

.frame-thumb--none { background: var(--surface-3); border: 1px dashed var(--border-light); }
.frame-thumb--none .frame-thumb-inner { background: linear-gradient(135deg,#bbb,#888); margin: 4px; }

/* ================================
   交互组件
================================ */
.slider-row { display: flex; align-items: center; gap: 10px; }
.slider-label { font-size: 11px; color: var(--text-muted); flex-shrink: 0; }
.slider {
  flex: 1; -webkit-appearance: none; appearance: none;
  height: 4px; border-radius: 2px; background: var(--surface-3); outline: none;
}
.slider::-webkit-slider-thumb {
  -webkit-appearance: none; width: 14px; height: 14px; border-radius: 50%;
  background: var(--accent); cursor: pointer; box-shadow: 0 0 0 3px rgba(124,107,255,0.2);
}
.slider-val { font-size: 12px; color: var(--accent); font-weight: 500; min-width: 38px; text-align: right; }

.color-row { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.color-swatch {
  width: 26px; height: 26px; border-radius: 50%; border: 2px solid transparent;
  cursor: pointer; transition: transform var(--transition); outline: 2px solid transparent; outline-offset: 2px;
}
.color-swatch:hover { transform: scale(1.15); }
.color-swatch.active { outline-color: var(--accent); }
.color-custom {
  width: 26px; height: 26px; border-radius: 50%; border: 2px solid var(--border-light);
  cursor: pointer; background: transparent; padding: 0; overflow: hidden;
}
.color-custom::-webkit-color-swatch { border: none; border-radius: 50%; }

.sub-label { font-size: 11px; color: var(--text-secondary); font-weight: 500; margin-bottom: 8px; margin-top: 14px; }
.sub-label:first-of-type { margin-top: 0; }
.drag-hint {
  margin-top: 12px; font-size: 11px; color: var(--text-muted);
  background: var(--surface-2); border-radius: var(--radius-sm);
  padding: 10px; line-height: 1.4; border-left: 3px solid var(--accent);
}

.shadow-row { display: flex; align-items: center; gap: 10px; }
.toggle-btn {
  background: var(--surface-3); color: var(--text-secondary);
  border: 1px solid var(--border); border-radius: var(--radius-sm);
  padding: 6px 14px; font-size: 12px; font-weight: 500; cursor: pointer;
}
.toggle-btn.on { background: var(--accent-dim); color: var(--accent); border-color: var(--accent); }
.shadow-slider-disabled { opacity: 0.3; pointer-events: none; }

.btn-download {
  width: 100%; background: linear-gradient(135deg, var(--accent), #9183ff);
  color: #fff; border: none; border-radius: var(--radius-md); padding: 14px;
  font-size: 15px; font-weight: 600; cursor: pointer;
  display: flex; align-items: center; justify-content: center; gap: 8px;
  transition: all var(--transition);
}
.btn-download:hover:not(:disabled) { transform: translateY(-2px); box-shadow: 0 6px 24px rgba(124,107,255,0.5); }
.btn-download:disabled { opacity: 0.4; cursor: not-allowed; }
.download-hint { margin-top: 10px; font-size: 12px; color: var(--text-muted); text-align: center; }


/* 导出格式 */
.export-row { display: flex; gap: 8px; margin-bottom: 10px; }
.export-fmt {
  flex: 1; padding: 7px; text-align: center;
  background: var(--surface-2); color: var(--text-secondary);
  border: 1px solid var(--border); border-radius: var(--radius-sm);
  font-size: 12px; font-weight: 600; cursor: pointer;
  transition: all var(--transition);
}
.export-fmt:hover { border-color: var(--accent); color: var(--text-primary); }
.export-fmt.active { border-color: var(--accent); background: var(--accent-dim); color: var(--accent); }
.jpeg-quality-row { margin-top: 6px; }

/* 渐变边框 */
.gradient-row {
  display: flex; align-items: center; gap: 10px; margin-top: 12px;
}
.gradient-color2 { display: flex; align-items: center; gap: 6px; }

/* 水印 */
.watermark-row { display: flex; align-items: center; gap: 10px; }
.watermark-input {
  flex: 1; padding: 6px 10px;
  background: var(--surface-3); color: var(--text-primary);
  border: 1px solid var(--border); border-radius: 6px;
  font-size: 12px; font-family: var(--font);
}
.watermark-input:disabled { opacity: 0.4; }
.watermark-input:focus { border-color: var(--accent); outline: none; }
.watermark-pos-grid { display: flex; gap: 6px; }

.footer { text-align: center; padding: 30px 24px; border-top: 1px solid var(--border); font-size: 12px; color: var(--text-muted); }

/* 缩略图删除按钮 */
.thumb-delete {
  position: absolute; top: 2px; right: 2px;
  width: 18px; height: 18px; border-radius: 50%;
  background: rgba(0,0,0,0.7); color: #fff;
  border: none; font-size: 11px; line-height: 18px;
  text-align: center; cursor: pointer;
  opacity: 0; transition: opacity var(--transition);
  padding: 0; z-index: 2;
}
.thumb-item:hover .thumb-delete { opacity: 1; }

/* 撤销按钮 */
.btn-undo {
  background: var(--surface-2); color: var(--text-secondary);
  border: 1px solid var(--border); border-radius: var(--radius-sm);
  padding: 6px 14px; font-size: 12px; font-weight: 500; cursor: pointer;
  transition: all var(--transition);
  display: flex; align-items: center; gap: 4px;
}
.btn-undo:hover { background: var(--surface-3); color: var(--text-primary); border-color: var(--accent); }
.btn-undo:disabled { opacity: 0.3; cursor: not-allowed; }

.header-divider {
  width: 1px; height: 24px;
  background: var(--border); margin: 0 4px;
}

@media (max-width: 1000px) {
  .workspace { grid-template-columns: 1fr; }

  /* Header 精简 */
  .header-inner {
    flex-wrap: wrap; gap: 8px;
    padding: 10px 16px;
  }
  .header-sub { display: none; }
  .header-divider { display: none; }
  .batch-actions {
    width: 100%; justify-content: space-between;
    gap: 6px; order: 10;
  }
  .batch-actions .btn-undo,
  .batch-actions .btn-secondary {
    font-size: 11px; padding: 5px 10px;
  }
  .btn-collage {
    font-size: 12px; padding: 6px 14px;
    order: 5;
  }

  /* 预览面板 — 移动端 sticky 紧凑预览 */
  .preview-panel {
    min-height: 0;
    max-height: 280px;
    position: sticky;
    top: 0;
    z-index: 50;
    border-radius: var(--radius-md);
    overflow: hidden;
  }
  .canvas-wrap {
    padding: 10px 10px 6px;
    min-height: 0;
  }
  .canvas-wrap canvas {
    max-height: 200px !important;
    width: auto !important;
  }
  .upload-zone {
    min-height: 280px;
    padding: 40px 20px;
  }
  .upload-icon { font-size: 36px; }
  .upload-title { font-size: 15px; }
  .upload-hint { font-size: 12px; }
  /* 缩略图条紧凑 */
  .thumbnail-outer { padding-top: 6px; }
  .thumb-item { width: 40px; height: 40px; }
  .btn-reupload { font-size: 11px; padding: 4px 10px; top: 8px; right: 8px; }

  /* 控制面板 */
  .main { padding: 16px 12px; }
  .panel-section { padding: 14px 14px; }

  /* 比例网格 — 移动端紧凑 */
  .ratio-grid { grid-template-columns: repeat(3, 1fr); gap: 5px; }
  .ratio-item { padding: 6px 2px; font-size: 11px; }
  .custom-ratio-row { padding: 6px 8px; }

  /* 边框选择 — 移动端自动换行 */
  .frame-grid { grid-template-columns: repeat(5, 1fr); gap: 6px; }
  .frame-item { padding: 6px 2px; }
  .frame-item span { font-size: 9px; }
  .frame-thumb { width: 44px; height: 36px; }

  /* 滑块行 */
  .slider-row { gap: 6px; }
  .slider-label { font-size: 10px; }
  .slider-val { font-size: 11px; min-width: 32px; }

  /* 下载按钮 */
  .btn-download { padding: 12px; font-size: 14px; }
}

@keyframes fadeIn { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: translateY(0); } }

/* ================================
   拼图模式
   ================================ */
.btn-collage {
  background: linear-gradient(135deg, var(--accent), #a78bfa);
  color: #fff; border: none; border-radius: var(--radius-sm);
  padding: 8px 20px; font-size: 14px; font-weight: 700; cursor: pointer;
  transition: all var(--transition);
  letter-spacing: 0.5px;
  animation: collage-pulse 2.5s ease-in-out infinite;
}
@keyframes collage-pulse {
  0%, 100% { box-shadow: 0 2px 8px rgba(124,107,255,0.3); }
  50% { box-shadow: 0 4px 20px rgba(124,107,255,0.6); }
}
.btn-collage:hover { transform: translateY(-2px); box-shadow: 0 6px 24px rgba(124,107,255,0.5); animation: none; }

.btn-collage-add {
  position: absolute; top: 12px; left: 12px;
  background: linear-gradient(135deg, var(--accent), #a78bfa);
  color: #fff; border: none; border-radius: var(--radius-sm);
  padding: 10px 20px; font-size: 14px; font-weight: 700;
  cursor: pointer; z-index: 10;
  transition: all var(--transition);
  box-shadow: 0 4px 16px rgba(124,107,255,0.4);
}
.btn-collage-add:hover { transform: translateY(-2px) scale(1.05); }
.btn-collage.active {
  background: #fff; color: var(--accent);
  box-shadow: 0 0 0 2px var(--accent);
}

.collage-panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  margin-bottom: 16px;
  animation: fadeIn 0.3s ease;
}

.layout-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 8px;
}
.layout-item {
  display: flex; flex-direction: column; align-items: center; gap: 6px;
  background: var(--surface-2); border: 2px solid transparent;
  border-radius: var(--radius-sm); padding: 10px 4px;
  cursor: pointer; transition: all var(--transition); color: var(--text-muted);
}
.layout-item svg { width: 40px; height: 30px; }
.layout-item span { font-size: 10px; }
.layout-item:hover { background: var(--surface-3); color: var(--text-primary); }
.layout-item.active {
  border-color: var(--accent); background: var(--accent-dim);
  color: var(--accent);
}

#layerLabel { color: var(--accent); font-weight: 600; }
.layer-actions {
  display: flex; gap: 8px; margin-top: 10px;
}
.layer-actions .btn-undo { flex: 1; justify-content: center; }