:root {
  --bg: #0d1117;
  --panel: #161b22;
  --border: #30363d;
  --text: #c9d1d9;
  --heading: #e6edf3;
  --accent: #58a6ff;
  --accent-dim: rgba(88, 166, 255, 0.12);
  --input-bg: #0d1117;
  --btn-bg: #238636;
  --btn-hover: #2ea043;
  --widget-bg: #1a1a3e;
  --widget-grid: rgba(88, 166, 255, 0.15);
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
}

header {
  padding: 16px 24px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}
header h1 {
  font-size: 18px;
  color: var(--heading);
  font-weight: 600;
}
header p {
  font-size: 13px;
  color: #8b949e;
  margin-top: 4px;
}

.header-left {
  min-width: 0;
}

.mode-toggle {
  display: flex;
  gap: 0;
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow: hidden;
  flex-shrink: 0;
}

.mode-btn {
  padding: 6px 18px;
  border: none;
  background: var(--panel);
  color: #8b949e;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition:
    background 0.15s,
    color 0.15s;
}
.mode-btn:hover {
  color: var(--text);
}
.mode-btn.active {
  background: var(--accent);
  color: #fff;
}

.mode-hint {
  font-size: 14px;
  color: var(--accent);
  font-weight: 500;
  margin-right: 8px;
  margin-left: auto;
  white-space: nowrap;
}

main {
  display: grid;
  grid-template-columns: 1fr 340px;
  gap: 16px;
  padding: 16px 24px;
  margin: 0 auto;
}

.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 16px;
}
.panel h2 {
  font-size: 13px;
  font-weight: 600;
  color: #8b949e;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 12px;
}

.panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}
.panel-header h2 {
  margin-bottom: 0;
}

.left-col {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.right-col {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

#svg {
  width: 100%;
  display: block;
  border-radius: 4px;
  background: #0a0e14;
  user-select: none;
  -webkit-user-select: none;
  touch-action: none;
}

#svg image {
  transition: opacity 0.15s;
}

.corner-circle {
  cursor: grab;
  filter: drop-shadow(0 0 4px rgba(88, 166, 255, 0.5));
  transition: r 0.1s;
}
.corner-circle:hover {
  r: 14;
}
.corner-circle.dragging {
  cursor: grabbing;
  r: 14;
}

.corner-label {
  font-size: 22px;
  fill: var(--text);
  font-family: monospace;
  pointer-events: none;
}

.corner-coord {
  font-size: 18px;
  fill: #8b949e;
  font-family: monospace;
  pointer-events: none;
}

.field-row {
  display: flex;
  gap: 12px;
  align-items: center;
}
.field-row label {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  color: #8b949e;
  flex: 1;
}
.field-row label span {
  min-width: 14px;
}
.field-row input {
  width: 100%;
  padding: 6px 8px;
  background: var(--input-bg);
  border: 1px solid var(--border);
  border-radius: 4px;
  color: var(--heading);
  font-size: 14px;
  font-family: monospace;
  outline: none;
}
.field-row input:focus {
  border-color: var(--accent);
}

.corner-inputs {
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.corner-input-row {
  display: flex;
  align-items: center;
  gap: 8px;
}
.corner-input-row .label {
  font-size: 13px;
  font-weight: 600;
  color: var(--accent);
  min-width: 28px;
  font-family: monospace;
}
.corner-input-row label {
  display: flex;
  align-items: center;
  gap: 4px;
  font-size: 13px;
  color: #8b949e;
  flex: 1;
}
.corner-input-row label span {
  min-width: 12px;
}
.corner-input-row input {
  width: 100%;
  padding: 5px 6px;
  background: var(--input-bg);
  border: 1px solid var(--border);
  border-radius: 4px;
  color: var(--heading);
  font-size: 13px;
  font-family: monospace;
  outline: none;
}
.corner-input-row input:focus {
  border-color: var(--accent);
}
.corner-input-row input.input-error {
  border-color: #f85149;
  background: rgba(248, 81, 73, 0.1);
}

#cssOutput {
  width: 100%;
  min-height: 80px;
  padding: 10px;
  background: var(--input-bg);
  border: 1px solid var(--border);
  border-radius: 4px;
  color: var(--accent);
  font-size: 12px;
  font-family: "Cascadia Code", "Fira Code", monospace;
  line-height: 1.6;
  resize: vertical;
  outline: none;
}

.btn-row {
  display: flex;
  gap: 8px;
  margin-top: 8px;
}

.btn {
  padding: 6px 14px;
  border: none;
  border-radius: 4px;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s;
}
.btn-copy {
  background: var(--btn-bg);
  color: white;
}
.btn-copy:hover {
  background: var(--btn-hover);
}
.btn-reset {
  background: var(--border);
  color: var(--text);
}
.btn-reset:hover {
  background: #484f58;
}

.btn-edit-field {
  padding: 4px 12px;
  border: 1px solid var(--accent);
  border-radius: 4px;
  background: transparent;
  color: var(--accent);
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  transition:
    background 0.15s,
    color 0.15s;
}
.btn-edit-field:hover {
  background: rgba(88, 166, 255, 0.1);
}

.btn-save-field {
  padding: 4px 12px;
  border: none;
  border-radius: 4px;
  background: var(--btn-bg);
  color: white;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s;
}
.btn-save-field:hover {
  background: var(--btn-hover);
}

.btn-cancel-field {
  padding: 4px 12px;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: transparent;
  color: var(--text);
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s;
}
.btn-cancel-field:hover {
  background: var(--border);
}

.field-size-stack {
  display: flex;
  align-items: stretch;
  gap: 8px;
}

.chain-link {
  display: none;
  align-items: center;
  justify-content: center;
  width: 32px;
  min-height: 56px;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: var(--input-bg);
  color: var(--accent);
  cursor: pointer;
  flex-shrink: 0;
  transition:
    background 0.15s,
    color 0.15s;
}
.chain-link:hover {
  background: rgba(88, 166, 255, 0.1);
}
.chain-link.unlocked {
  color: #8b949e;
}
.chain-link.visible {
  display: flex;
}

.field-stack-inputs {
  display: flex;
  flex-direction: column;
  gap: 6px;
  flex: 1;
}
.field-stack-inputs label {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  color: #8b949e;
}
.field-stack-inputs label span {
  min-width: 14px;
}
.field-stack-inputs input {
  width: 100%;
  padding: 6px 8px;
  background: var(--input-bg);
  border: 1px solid var(--border);
  border-radius: 4px;
  color: var(--heading);
  font-size: 14px;
  font-family: monospace;
  outline: none;
}
.field-stack-inputs input:focus {
  border-color: var(--accent);
}
.field-stack-inputs input:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.field-row input:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.field-edit-options {
  display: none;
  margin-top: 10px;
  flex-direction: column;
  gap: 8px;
}
.field-edit-options.visible {
  display: flex;
}

.field-save-row {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 8px;
}

.checkbox-label {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  color: #8b949e;
  cursor: pointer;
}
.checkbox-label input[type="checkbox"] {
  accent-color: var(--accent);
}

#fieldContainer {
  width: 100%;
  overflow: hidden;
  border-radius: 4px;
  background: #080b10;
  border: 2px solid #1a1f2a;
  position: relative;
}

.left-col.drag-over {
  outline: 2px dashed var(--accent);
  outline-offset: -2px;
  border-radius: 8px;
}

#field {
  position: absolute;
  top: 0;
  left: 0;
  transform-origin: 0 0;
  background-color: #0c1018;
  background-repeat: no-repeat;
  background-position: center;
  transition: opacity 0.15s;
}

body.file-dragging #field {
  opacity: 0.1;
}

body.file-dragging #svg image {
  opacity: 0.1;
}

body.file-dragging .left-col {
  outline: 3px dashed rgba(88, 166, 255, 0.9);
  outline-offset: -3px;
  border-radius: 8px;
}

body.file-dragging .left-col.drag-over {
  outline: 5px dashed var(--accent);
  outline-offset: -5px;
  border-radius: 8px;
  background: rgba(88, 166, 255, 0.15);
}

body.file-dragging #bgPanel {
  outline: 2px dashed rgba(88, 166, 255, 0.7);
  outline-offset: -2px;
}

body.file-dragging #bgPanel.drag-over {
  outline: 3px dashed var(--accent);
  outline-offset: -3px;
  background: rgba(88, 166, 255, 0.08);
}

body.file-dragging #widgetPanel {
  outline: 2px dashed rgba(88, 166, 255, 0.7);
  outline-offset: -2px;
}

body.file-dragging #widgetPanel.drag-over {
  outline: 3px dashed var(--accent);
  outline-offset: -3px;
  background: rgba(88, 166, 255, 0.08);
}

#widget {
  position: absolute;
  top: 0;
  left: 0;
  transform-origin: 0 0;
  background-color: var(--widget-bg);
  background-image:
    linear-gradient(45deg, var(--widget-grid) 25%, transparent 25%, transparent 75%, var(--widget-grid) 75%),
    linear-gradient(45deg, var(--widget-grid) 25%, transparent 25%, transparent 75%, var(--widget-grid) 75%);
  background-size: 30px 30px;
  background-position:
    0 0,
    15px 15px;
  border: 2px solid var(--accent);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

#widget span {
  color: rgba(255, 255, 255, 0.7);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 2px;
  text-shadow: 0 1px 3px rgba(0, 0, 0, 0.5);
  pointer-events: none;
}

.error-msg {
  color: #f85149;
  font-size: 12px;
  font-style: italic;
}

body.mode-edit .left-col .panel:first-child {
  display: flex;
}
body.mode-edit .left-col .panel:last-child {
  display: none;
}
body.mode-edit .right-col {
  display: flex;
}

body.mode-preview .left-col .panel:first-child {
  display: none;
}
body.mode-preview .left-col .panel:last-child {
  display: flex;
}
body.mode-preview .right-col {
  display: flex;
}

body.mode-preview .left-col {
  width: 100%;
}

.bg-controls {
  display: flex;
  align-items: center;
  gap: 8px;
}

.widget-img-controls {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 8px;
}

.widget-paste-input {
  width: 100%;
  padding: 6px 8px;
  margin-top: 8px;
  background: var(--input-bg);
  border: 1px dashed var(--border);
  border-radius: 4px;
  color: #8b949e;
  font-size: 13px;
  outline: none;
  cursor: pointer;
  transition: border-color 0.15s;
}
.widget-paste-input:focus {
  border-color: var(--accent);
  border-style: solid;
}

#bgObjectFit {
  padding: 4px 8px;
  background: var(--input-bg);
  border: 1px solid var(--border);
  border-radius: 4px;
  color: var(--heading);
  font-size: 13px;
  font-family: monospace;
  outline: none;
  cursor: pointer;
}
#bgObjectFit:focus {
  border-color: var(--accent);
}

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