* { margin: 0; padding: 0; box-sizing: border-box; -webkit-tap-highlight-color: transparent; }

:root {
  --primary: #0071E3;
  --primary-hover: #0077ED;
  --primary-light: rgba(0,113,227,0.08);
  --danger: #FF3B30;
  --success: #34C759;
  --bg: #FBFBFD;
  --card-bg: #FFFFFF;
  --text: #1D1D1F;
  --text-secondary: #6E6E73;
  --text-tertiary: #AEAEB2;
  --border: rgba(0,0,0,0.04);
  --border-strong: rgba(0,0,0,0.1);
  --shadow: 0 4px 16px rgba(0,0,0,0.04);
  --shadow-lg: 0 12px 40px rgba(0,0,0,0.08);
  --radius: 20px;
  --radius-sm: 12px;
  --tab-height: 72px;
  --header-height: 52px;
  --safe-top: env(safe-area-inset-top);
  --safe-bottom: env(safe-area-inset-bottom);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "PingFang SC", "Helvetica Neue", sans-serif;
  background: var(--bg); color: var(--text); overflow: hidden; height: 100vh;
  padding-top: var(--safe-top); padding-bottom: var(--safe-bottom);
  -webkit-font-smoothing: antialiased;
}

#app { display: flex; flex-direction: column; height: 100vh; }

/* ========== Header ========== */
.app-header {
  height: var(--header-height); display: flex; align-items: center;
  justify-content: center; background: rgba(251,251,253,0.72);
  backdrop-filter: saturate(180%) blur(20px); -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--border); flex-shrink: 0;
  padding-top: var(--safe-top);
}
.app-header h1 {
  font-size: 16px; font-weight: 600; letter-spacing: -0.01em; color: var(--text);
}

/* ========== Tab Content ========== */
.tab-content {
  flex: 1; overflow-y: auto; -webkit-overflow-scrolling: touch;
  padding: 24px 28px; padding-bottom: calc(var(--tab-height) + 24px + var(--safe-bottom));
}

.tab-panel { display: none; }
.tab-panel.active { display: block; }
.hidden { display: none !important; }

/* ========== Tab Bar ========== */
.tab-bar {
  position: fixed; bottom: 0; left: 0; right: 0;
  height: calc(var(--tab-height) + var(--safe-bottom));
  padding-bottom: var(--safe-bottom);
  background: rgba(251,251,253,0.72);
  backdrop-filter: saturate(180%) blur(20px); -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-top: 1px solid var(--border);
  display: flex; align-items: center; justify-content: space-around; z-index: 100;
}
.tab-btn {
  display: flex; flex-direction: column; align-items: center; gap: 4px;
  background: none; border: none; color: var(--text-tertiary);
  font-size: 10px; font-weight: 500; cursor: pointer; padding: 8px 16px;
  transition: color 0.3s;
}
.tab-btn.active { color: var(--primary); }
.tab-btn.pulse { animation: tabPulse 0.6s ease; }
@keyframes tabPulse { 0%,100% { transform: scale(1); } 50% { transform: scale(1.2); } }
.tab-btn svg { width: 24px; height: 24px; }

/* ========== Fly Thumbnail Animation ========== */
.fly-thumbnail {
  position: fixed; z-index: 999; pointer-events: none;
  border-radius: 8px; box-shadow: 0 8px 32px rgba(0,0,0,0.25);
}

/* ========== Buttons ========== */
.btn-primary {
  background: var(--primary); color: #fff; border: none; border-radius: 980px;
  padding: 11px 22px; font-size: 14px; font-weight: 400; cursor: pointer;
  transition: background 0.3s, transform 0.15s; white-space: nowrap;
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  letter-spacing: -0.01em;
}
.btn-primary:hover { background: var(--primary-hover); }
.btn-primary:disabled { opacity: 0.4; cursor: not-allowed; }
.btn-primary:active:not(:disabled) { transform: scale(0.97); }
.btn-sm { padding: 8px 16px; font-size: 13px; }
.btn-outline {
  background: none; border: 1px solid var(--border-strong); border-radius: 980px;
  padding: 7px 16px; font-size: 13px; cursor: pointer; color: var(--text-secondary);
  transition: background 0.3s, color 0.3s;
}
.btn-outline:hover { background: rgba(0,0,0,0.04); color: var(--text); }
.btn-text {
  background: none; border: none; color: var(--primary); font-size: 14px;
  cursor: pointer; padding: 6px 10px; font-weight: 400;
}
.btn-text:hover { text-decoration: underline; }
.btn-danger {
  background: var(--danger); color: #fff; border: none; border-radius: 980px;
  padding: 7px 16px; font-size: 13px; cursor: pointer;
}
.btn-group { display: flex; gap: 8px; }
.input-number {
  width: 72px; padding: 8px 12px; border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm); font-size: 14px; text-align: center;
  outline: none; transition: border-color 0.3s; background: var(--card-bg);
}
.input-number:focus { border-color: var(--primary); }

/* ========== Generate Tab ========== */
#tab-generate { position: relative; }

/* Row 1: Upload left + Preview right */
.workspace-top {
  display: flex; gap: 24px; align-items: stretch; margin-top: 4px;
}
.workspace-left {
  flex: 0 0 280px; min-width: 0; display: flex; flex-direction: column;
}
.workspace-right {
  flex: 1; min-width: 0; display: flex; flex-direction: column;
}

/* Upload Area */
.upload-area {
  background: var(--card-bg); border-radius: var(--radius);
  overflow: hidden;
}
.upload-placeholder {
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  padding: 48px 24px; cursor: pointer;
  border: 2px dashed var(--border-strong); border-radius: var(--radius);
  transition: border-color 0.3s, background 0.3s;
}
.upload-placeholder:hover, .upload-placeholder.dragover {
  border-color: var(--primary); background: var(--primary-light);
}
.upload-placeholder svg { opacity: 0.35; }
.upload-placeholder p { margin-top: 12px; color: var(--text-secondary); font-size: 14px; }
.upload-placeholder .hint { font-size: 12px; color: var(--text-tertiary); margin-top: 4px; }
.preview-area { padding: 20px; text-align: center; }
.preview-area img { max-width: 100%; max-height: 240px; border-radius: var(--radius-sm); }
.img-info { font-size: 12px; color: var(--text-secondary); margin-top: 10px; text-align: center; }

/* Resize Controls */
.controls-card {
  background: var(--card-bg); border-radius: var(--radius);
  padding: 16px 20px; margin-top: 12px;
}
.controls-row {
  display: flex; align-items: center; gap: 12px; flex-wrap: wrap;
}
.controls-row label {
  font-size: 13px; color: var(--text-secondary); display: flex; align-items: center; gap: 8px;
}
.toggle-label {
  font-size: 13px; color: var(--text-secondary);
  display: flex; align-items: center; gap: 6px; cursor: pointer;
}
.toggle-label input[type="checkbox"] {
  width: 16px; height: 16px; accent-color: var(--primary);
}
.range-label {
  font-size: 13px; color: var(--text-secondary);
  display: flex; align-items: center; gap: 6px; white-space: nowrap;
}
.input-range {
  width: 80px; accent-color: var(--primary); cursor: pointer;
}
.range-label span {
  min-width: 24px; text-align: center; font-weight: 600; color: var(--text); font-size: 13px;
}

/* Right panel: empty state */
.right-empty-state {
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  flex: 1; padding: 48px 24px; text-align: center;
  border: 2px dashed var(--border-strong); border-radius: var(--radius);
  background: var(--card-bg);
}
.right-empty-state svg { opacity: 0.3; }
.right-empty-state p { margin-top: 14px; color: var(--text-tertiary); font-size: 13px; }

/* Right panel: selected variant preview */
.selected-variant-preview {
  flex: 1; background: var(--card-bg); border-radius: var(--radius);
  display: flex; align-items: center; justify-content: center;
  cursor: pointer; overflow: hidden; position: relative; min-height: 240px;
}
.selected-variant-preview img {
  max-width: 100%; max-height: 100%; image-rendering: pixelated;
  border-radius: var(--radius-sm);
}
.preview-click-hint {
  position: absolute; bottom: 12px; right: 12px;
  background: rgba(0,0,0,0.5); color: #fff;
  padding: 4px 10px; border-radius: 980px; font-size: 11px;
  opacity: 0; transition: opacity 0.3s; pointer-events: none;
}
.selected-variant-preview:hover .preview-click-hint { opacity: 1; }

/* ========== Variant Strip (Row 2: 5 cards full width) ========== */
.variant-strip {
  display: grid; grid-template-columns: repeat(5, 1fr); gap: 12px; margin-top: 20px;
}
.strip-card {
  background: var(--card-bg); border-radius: var(--radius-sm); overflow: hidden;
  border: 2px solid transparent; cursor: pointer;
  transition: border-color 0.3s, box-shadow 0.3s, transform 0.2s;
}
.strip-card:hover {
  box-shadow: var(--shadow); transform: translateY(-2px);
}
.strip-card.selected {
  border-color: var(--primary); box-shadow: 0 0 0 1px var(--primary), var(--shadow-lg);
}
.strip-card img {
  width: 100%; display: block; image-rendering: pixelated;
}
.strip-card-label {
  padding: 6px 8px; font-size: 11px; color: var(--text-secondary);
  text-align: center; white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}

/* ========== Pattern Modal (pixel grid viewer) ========== */
.pattern-modal {
  position: fixed; inset: 0; background: rgba(0,0,0,0.6); z-index: 300;
  display: flex; align-items: center; justify-content: center; padding: 16px;
  backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px);
}
.pattern-modal.hidden { display: none; }
.pattern-modal-content {
  background: var(--card-bg); border-radius: var(--radius);
  width: 95vw; height: 92vh; display: flex; flex-direction: column;
  overflow: hidden; box-shadow: 0 20px 60px rgba(0,0,0,0.3);
}
.pattern-modal-header {
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px 20px; border-bottom: 1px solid var(--border); flex-shrink: 0;
}
.pattern-modal-header h3 { font-size: 16px; font-weight: 600; }
.pattern-modal-actions { display: flex; gap: 8px; align-items: center; }
.pattern-modal-body {
  flex: 1; overflow: hidden; display: flex; align-items: center;
  justify-content: center; padding: 12px;
}
.pinch-zoom-container {
  width: 100%; height: 100%; overflow: hidden; touch-action: none;
  display: flex; align-items: center; justify-content: center; position: relative;
  cursor: grab;
}
.pinch-zoom-container .pattern-grid {
  transform-origin: center center;
}
.pattern-modal-summary {
  flex-shrink: 0; max-height: 140px; overflow-y: auto;
  padding: 10px 20px; border-top: 1px solid var(--border); font-size: 12px;
}

/* ========== Gray secondary button ========== */
.btn-secondary {
  background: #E5E5EA; color: #1D1D1F; border: none; border-radius: 980px;
  padding: 8px 16px; font-size: 13px; font-weight: 400; cursor: pointer;
  transition: background 0.3s, transform 0.15s; white-space: nowrap;
}
.btn-secondary:hover { background: #D1D1D6; }
.btn-secondary:active { transform: scale(0.97); }

/* ========== Loading ========== */
.loading { text-align: center; padding: 48px; }
.loading p { color: var(--text-secondary); font-size: 14px; margin-top: 4px; }
.spinner {
  width: 32px; height: 32px; border: 2.5px solid var(--border-strong);
  border-top-color: var(--primary); border-radius: 50%;
  animation: spin 0.8s linear infinite; margin: 0 auto 12px;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ========== Result / Pattern ========== */
.pattern-wrapper {
  background: var(--card-bg); border-radius: var(--radius);
  padding: 20px; overflow-x: auto;
}
.pattern-grid {
  display: inline-grid; gap: 0; border: 1px solid var(--border-strong);
  font-size: 7px; line-height: 1;
}
.pattern-cell {
  width: 22px; height: 22px; display: flex; align-items: center; justify-content: center;
  border: 0.5px solid rgba(0,0,0,0.06); font-weight: 600; font-family: monospace;
  color: #333; text-shadow: 0 0 2px rgba(255,255,255,0.8);
}
.color-summary {
  margin-top: 20px; background: var(--card-bg); border-radius: var(--radius);
  padding: 20px;
}
.color-summary h3 { font-size: 16px; font-weight: 600; margin-bottom: 14px; letter-spacing: -0.02em; }
.color-list { display: grid; grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: 8px; }
.color-item {
  display: flex; align-items: center; gap: 10px; padding: 8px 12px;
  background: var(--bg); border-radius: var(--radius-sm); font-size: 13px;
}
.color-swatch { width: 22px; height: 22px; border-radius: 6px; border: 1px solid var(--border-strong); flex-shrink: 0; }
.color-info { flex: 1; min-width: 0; }
.color-code { font-weight: 600; font-size: 12px; }
.color-count { color: var(--text-secondary); font-size: 12px; }
.result-actions { display: flex; gap: 10px; margin-top: 16px; }
.result-actions button { flex: 1; }

/* ========== Section Header ========== */
.section-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 20px; }
.section-header h2 { font-size: 22px; font-weight: 600; letter-spacing: -0.02em; }

/* ========== Masonry Grid ========== */
.masonry-grid { columns: 2; column-gap: 14px; }
.masonry-item {
  break-inside: avoid; margin-bottom: 14px; background: var(--card-bg);
  border-radius: var(--radius); overflow: hidden;
  transition: box-shadow 0.3s, transform 0.3s;
}
.masonry-item:hover { box-shadow: var(--shadow-lg); transform: translateY(-2px); }
.masonry-item img { width: 100%; display: block; }
.masonry-item-info { padding: 14px; }
.masonry-item-info .date { font-size: 12px; color: var(--text-tertiary); }
.masonry-item-info .title { font-size: 14px; font-weight: 500; margin-top: 3px; }
.masonry-item-actions { display: flex; gap: 6px; margin-top: 10px; }
.empty-hint { text-align: center; color: var(--text-tertiary); padding: 64px 0; font-size: 14px; grid-column: 1/-1; }

/* ========== Gallery ========== */
.gallery-upload { margin-bottom: 20px; }

/* ========== Modal ========== */
.modal {
  position: fixed; inset: 0; background: rgba(0,0,0,0.45); z-index: 200;
  display: flex; align-items: center; justify-content: center; padding: 24px;
  backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px);
}
.modal.hidden { display: none; }
.modal-content {
  background: var(--card-bg); border-radius: var(--radius); width: 100%;
  max-width: 600px; max-height: 80vh; overflow-y: auto; box-shadow: var(--shadow-lg);
}
.modal-header {
  display: flex; align-items: center; justify-content: space-between;
  padding: 18px 24px; border-bottom: 1px solid var(--border);
}
.modal-header h3 { font-size: 17px; font-weight: 600; letter-spacing: -0.02em; }
.modal-close {
  background: rgba(0,0,0,0.04); border: none; border-radius: 50%;
  width: 30px; height: 30px; font-size: 20px; cursor: pointer;
  color: var(--text-secondary); display: flex; align-items: center; justify-content: center;
  transition: background 0.3s;
}
.modal-close:hover { background: rgba(0,0,0,0.08); }
.modal-body { padding: 24px; }
.modal-body img { width: 100%; border-radius: var(--radius-sm); }
.modal-body input[type="text"] {
  width: 100%; padding: 10px 14px; border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm); font-size: 14px; margin-top: 8px; outline: none;
  transition: border-color 0.3s;
}
.modal-body input[type="text"]:focus { border-color: var(--primary); }
.modal-body .modal-actions { display: flex; gap: 8px; margin-top: 14px; }
.modal-body .modal-actions button { flex: 1; padding: 10px; border-radius: 980px; font-size: 14px; cursor: pointer; }