:root {
  --sidebar-bg: #f2f1ed;
  --preview-bg: #fafaf8;
  --card: #ffffff;
  --text: #1a1a1a;
  --text-dim: #6e6e73;
  --accent: #2563eb;
  --accent-soft: rgba(37, 99, 235, 0.08);
  --border: rgba(0, 0, 0, 0.08);
  --border-strong: rgba(0, 0, 0, 0.14);
  --shadow-card: 0 1px 2px rgba(0,0,0,0.03), 0 6px 20px rgba(0,0,0,0.04);
  --shadow-lift: 0 2px 4px rgba(0,0,0,0.04), 0 12px 40px rgba(0,0,0,0.08);
  --radius-card: 16px;
  --radius-input: 10px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html, body {
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro", "SF Pro Display", "Inter", system-ui, sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  background: var(--sidebar-bg);
  color: var(--text);
  height: 100vh;
  overflow: hidden;
  font-size: 14px;
  letter-spacing: -0.01em;
}

.layout {
  display: grid;
  grid-template-columns: 320px 1fr;
  height: 100vh;
}

/* -- Sidebar -- */
.sidebar {
  background: var(--sidebar-bg);
  border-right: 1px solid var(--border);
  overflow-y: auto;
  padding: 28px 24px 40px;
}

.sidebar::-webkit-scrollbar { width: 8px; }
.sidebar::-webkit-scrollbar-track { background: transparent; }
.sidebar::-webkit-scrollbar-thumb { background: rgba(0,0,0,0.08); border-radius: 4px; }
.sidebar::-webkit-scrollbar-thumb:hover { background: rgba(0,0,0,0.14); }

.tab-bar {
  display: flex;
  align-items: stretch;
  gap: 2px;
  padding: 8px 12px 0;
  overflow-x: auto;
  border-bottom: 1px solid var(--border);
  margin-bottom: 8px;
  scrollbar-width: none;
}
.tab-bar::-webkit-scrollbar { display: none; }
.tab-item {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 8px 14px;
  font-size: 12px;
  font-weight: 500;
  color: var(--text-dim);
  border-radius: 8px 8px 0 0;
  cursor: pointer;
  white-space: nowrap;
  max-width: 160px;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: all 0.15s ease;
  user-select: none;
  border-bottom: 2px solid transparent;
}
.tab-item.active {
  color: var(--accent);
  background: var(--accent-soft);
  border-bottom-color: var(--accent);
}
.tab-item:hover:not(.active) { background: rgba(0,0,0,0.03); }
.tab-name { cursor: default; }
.tab-name[contenteditable="true"] {
  cursor: text;
  outline: none;
  background: rgba(37, 99, 235, 0.06);
  border-radius: 4px;
  padding: 1px 4px;
  margin: -1px -4px;
}
.tab-add {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  border-radius: 6px;
  font-size: 16px;
  color: var(--text-dim);
  cursor: pointer;
  flex-shrink: 0;
  align-self: center;
}
.tab-add:hover { background: rgba(0,0,0,0.04); color: var(--accent); }

.tab-ctx {
  position: fixed;
  z-index: 9999;
  min-width: 160px;
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(20px) saturate(1.8);
  -webkit-backdrop-filter: blur(20px) saturate(1.8);
  border: 1px solid rgba(0, 0, 0, 0.12);
  border-radius: 8px;
  padding: 4px;
  box-shadow:
    0 0 0 0.5px rgba(0, 0, 0, 0.05),
    0 3px 8px rgba(0, 0, 0, 0.08),
    0 12px 30px rgba(0, 0, 0, 0.10);
  opacity: 0;
  transform: scale(0.96) translateY(-2px);
  transform-origin: top left;
  animation: ctx-in 0.12s ease-out forwards;
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro", system-ui, sans-serif;
}
@keyframes ctx-in {
  to { opacity: 1; transform: scale(1) translateY(0); }
}
.tab-ctx-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 6px 12px;
  font-size: 13px;
  font-weight: 400;
  color: var(--text);
  border-radius: 5px;
  cursor: default;
  user-select: none;
  letter-spacing: -0.01em;
  transition: background 0.06s;
}
.tab-ctx-item:hover {
  background: var(--accent);
  color: #fff;
}
.tab-ctx-item:hover .tab-ctx-icon {
  color: #fff;
}
.tab-ctx-item.destructive:hover {
  background: #e53e3e;
  color: #fff;
}
.tab-ctx-item.destructive:hover .tab-ctx-icon {
  color: #fff;
}
.tab-ctx-icon {
  width: 16px;
  text-align: center;
  font-size: 13px;
  color: var(--text-dim);
  flex-shrink: 0;
}
.tab-ctx-sep {
  height: 1px;
  background: rgba(0, 0, 0, 0.08);
  margin: 4px 8px;
}
.tab-ctx-item.disabled {
  opacity: 0.35;
  pointer-events: none;
}

.brand {
  padding: 4px 4px 24px;
  margin-bottom: 8px;
}

.brand h1 {
  font-size: 24px;
  font-weight: 600;
  letter-spacing: -0.035em;
  color: var(--text);
  line-height: 1.1;
  margin-bottom: 6px;
}

.brand .tagline {
  font-size: 12px;
  font-weight: 300;
  color: var(--text-dim);
  letter-spacing: -0.005em;
}

.snap-toggle {
  margin-top: 10px;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px 4px 8px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: transparent;
  color: var(--text-dim);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: -0.005em;
  cursor: pointer;
  transition: color 0.15s ease, border-color 0.15s ease, background-color 0.15s ease;
}

.snap-toggle:hover {
  color: var(--text);
  border-color: var(--text-dim);
}

.snap-toggle .snap-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--text-dim);
  opacity: 0.4;
  transition: background-color 0.15s ease, opacity 0.15s ease;
}

.snap-toggle.on {
  color: var(--accent);
  border-color: var(--accent);
  background: var(--accent-soft);
}

.snap-toggle.on .snap-dot {
  background: var(--accent);
  opacity: 1;
}

body.snap-off .default-tick {
  opacity: 0.08;
}

body.snap-off .range-row.at-default .default-tick {
  opacity: 0.2;
}

/* -- Accordion card -- */
.card {
  background: var(--card);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-card);
  margin-bottom: 16px;
  overflow: hidden;
}

.card[open] {
  box-shadow: var(--shadow-lift);
}

.card > summary {
  list-style: none;
  cursor: pointer;
  padding: 18px 22px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  user-select: none;
  transition: background 0.15s ease;
}

.card > summary::-webkit-details-marker { display: none; }
.card > summary:hover { background: rgba(0,0,0,0.015); }

.card-label {
  font-size: 10px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.22em;
  color: var(--text-dim);
}

.card-caret {
  width: 18px;
  height: 18px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-dim);
  transition: transform 0.2s ease;
}

.card[open] .card-caret { transform: rotate(180deg); }

.card-body {
  padding: 4px 22px 22px;
}

.field {
  margin-bottom: 16px;
}

.field:last-child { margin-bottom: 0; }

.field label,
.toggle-row > span {
  display: block;
  font-size: 12px;
  font-weight: 500;
  color: var(--text);
  margin-bottom: 8px;
  letter-spacing: -0.005em;
}

.field input[type="text"],
.field input[type="number"],
.field textarea,
.field select {
  width: 100%;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius-input);
  padding: 11px 13px;
  color: var(--text);
  font-family: inherit;
  font-size: 13px;
  font-weight: 400;
  letter-spacing: -0.005em;
  outline: none;
  transition: border-color 0.15s, box-shadow 0.15s;
  appearance: none;
  -webkit-appearance: none;
}

.field select {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8' fill='none'%3E%3Cpath d='M1 1L6 6L11 1' stroke='%236e6e73' stroke-width='1.5' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 14px center;
  padding-right: 36px;
  cursor: pointer;
}

.field input:hover,
.field textarea:hover,
.field select:hover {
  border-color: var(--border-strong);
}

.field input:focus,
.field textarea:focus,
.field select:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

.field input::placeholder { color: #b0b0b5; }

.field textarea {
  resize: vertical;
  min-height: 72px;
  line-height: 1.5;
}

.field input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 4px;
  background: rgba(0,0,0,0.08);
  border-radius: 999px;
  outline: none;
  padding: 0;
  border: none;
}

.field input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: #ffffff;
  border: 1px solid var(--border-strong);
  box-shadow: 0 1px 3px rgba(0,0,0,0.12);
  cursor: grab;
  transition: transform 0.12s ease;
}

.field input[type="range"]::-webkit-slider-thumb:active { cursor: grabbing; transform: scale(1.08); }

.field input[type="range"]::-moz-range-thumb {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: #ffffff;
  border: 1px solid var(--border-strong);
  box-shadow: 0 1px 3px rgba(0,0,0,0.12);
  cursor: grab;
}

.range-row {
  display: flex;
  align-items: center;
  gap: 14px;
}

.range-row input[type="range"] { flex: 1; }

.range-track-wrap {
  position: relative;
  flex: 1;
}

.default-tick {
  position: absolute;
  width: 2px;
  height: 12px;
  background: var(--text-dim);
  opacity: 0.25;
  top: 50%;
  transform: translate(-50%, -50%);
  border-radius: 1px;
  pointer-events: none;
  transition: opacity 0.2s ease, background-color 0.2s ease;
}

.range-row.at-default .default-tick {
  background: var(--accent);
  opacity: 0.5;
}

.range-val {
  font-variant-numeric: tabular-nums;
  font-feature-settings: "tnum";
  font-size: 12px;
  font-weight: 500;
  color: var(--accent);
  min-width: 44px;
  text-align: right;
  padding: 2px 8px;
  border-radius: 6px;
  transition: background-color 0.2s ease;
}

.range-row.at-default .range-val {
  background: var(--accent-soft);
}

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

.color-input-wrap {
  display: flex;
  align-items: center;
  gap: 10px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius-input);
  padding: 6px 10px;
  transition: border-color 0.15s, box-shadow 0.15s;
}

.color-input-wrap:focus-within {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

.color-input-wrap input[type="color"] {
  width: 28px;
  height: 28px;
  border: 1px solid var(--border);
  border-radius: 6px;
  cursor: pointer;
  background: none;
  padding: 0;
  flex-shrink: 0;
  appearance: none;
  -webkit-appearance: none;
}

.color-input-wrap input[type="color"]::-webkit-color-swatch-wrapper { padding: 0; }
.color-input-wrap input[type="color"]::-webkit-color-swatch { border: none; border-radius: 5px; }

.color-input-wrap input[type="text"] {
  flex: 1;
  border: none;
  padding: 6px 0;
  font-size: 13px;
  background: transparent;
  outline: none;
  color: var(--text);
  font-variant-numeric: tabular-nums;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  height: 44px;
  padding: 0 18px;
  border-radius: var(--radius-input);
  font-family: inherit;
  font-size: 14px;
  font-weight: 500;
  letter-spacing: -0.005em;
  border: 1px solid transparent;
  cursor: pointer;
  transition: all 0.15s ease;
  width: 100%;
}

.btn-primary {
  background: var(--accent);
  color: #ffffff;
  box-shadow: 0 1px 2px rgba(37, 99, 235, 0.25);
}

.btn-primary:hover {
  background: #1d4fd1;
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.3);
  transform: translateY(-1px);
}

.btn-primary:active { transform: translateY(0); }

.btn-secondary {
  background: var(--card);
  color: var(--text);
  border-color: var(--border);
}

.btn-secondary:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.3);
  backdrop-filter: blur(4px);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  animation: fadeIn 0.15s ease;
}
.modal-card {
  background: var(--card);
  border-radius: var(--radius-card);
  box-shadow: 0 8px 40px rgba(0,0,0,0.15);
  padding: 28px;
  max-width: 400px;
  width: 90%;
}
.modal-card h3 { font-size: 16px; font-weight: 600; margin-bottom: 8px; }
.modal-card p { font-size: 13px; color: var(--text-dim); margin-bottom: 20px; line-height: 1.5; }
.modal-actions { display: flex; gap: 10px; justify-content: flex-end; }
.modal-actions .btn { width: auto; }
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }

.btn-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-top: 12px;
}

.toggle-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 4px 0;
  margin-bottom: 14px;
}

.toggle-row:last-child { margin-bottom: 0; }
.toggle-row > span { margin-bottom: 0; }

/* iOS-style switch */
.switch {
  position: relative;
  display: inline-block;
  width: 38px;
  height: 22px;
  flex-shrink: 0;
}

.switch input {
  opacity: 0;
  width: 0;
  height: 0;
}

.switch-slider {
  position: absolute;
  cursor: pointer;
  inset: 0;
  background: rgba(0,0,0,0.14);
  border-radius: 999px;
  transition: background 0.2s ease;
}

.switch-slider::before {
  content: "";
  position: absolute;
  height: 18px;
  width: 18px;
  left: 2px;
  top: 2px;
  background: #ffffff;
  border-radius: 50%;
  box-shadow: 0 1px 3px rgba(0,0,0,0.2);
  transition: transform 0.2s ease;
}

.switch input:checked + .switch-slider { background: var(--accent); }
.switch input:checked + .switch-slider::before { transform: translateX(16px); }

/* -- Preview -- */
.preview-area {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: var(--preview-bg);
  overflow: hidden;
  position: relative;
  padding: 12px;
}

.preview-frame {
  background: transparent;
  border-radius: 4px;
  overflow: hidden;
  position: relative;
}

.export-boundary {
  position: absolute;
  border: 3px dashed rgba(37, 99, 235, 0.7);
  pointer-events: none;
  z-index: 20;
  box-shadow: 0 0 0 1px rgba(37, 99, 235, 0.15);
}

.preview-label {
  font-size: 11px;
  font-weight: 500;
  color: var(--text-dim);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.preview-frame iframe {
  border: none;
  transform-origin: top left;
}

.preview-status {
  position: absolute;
  bottom: 20px;
  right: 20px;
  font-size: 11px;
  font-weight: 500;
  color: var(--text-dim);
  background: var(--card);
  padding: 8px 14px;
  border-radius: 999px;
  border: 1px solid var(--border);
  box-shadow: var(--shadow-card);
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.005em;
}
#drop-zone.drag-over { border-color: var(--accent); background: rgba(0,122,255,0.05); }
#bg-drop-zone.drag-over { border-color: var(--accent); background: rgba(0,122,255,0.05); }
.drop-zone-actions {
  display: flex;
  gap: 8px;
  margin-top: 8px;
}
.drop-zone-clear {
  font-size: 11px;
  font-weight: 500;
  color: var(--text-dim);
  cursor: pointer;
  padding: 4px 10px;
  border-radius: 6px;
  background: rgba(0,0,0,0.04);
  border: none;
  font-family: inherit;
  transition: all 0.15s ease;
}
.drop-zone-clear:hover {
  background: rgba(229, 62, 62, 0.08);
  color: #e53e3e;
}