:root {
  color-scheme: dark;
  --bg: #0f1115;
  --panel: #171b22;
  --panel-2: #1e2430;
  --text: #e6e9ef;
  --muted: #9ea7b8;
  --border: #2d3645;
  --accent: #4da3ff;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Inter, Segoe UI, Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
}

.app {
  min-height: 100vh;
  display: grid;
  grid-template-columns: minmax(280px, 420px) 1fr;
  gap: 16px;
  padding: 16px;
  align-items: start;
}

.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
}

h1 {
  margin: 0 0 16px;
  font-size: 1.2rem;
}

.row {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-bottom: 12px;
}

.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.actions {
  display: flex;
  flex-direction: row;
  gap: 8px;
  flex-wrap: wrap;
}

label,
legend,
.help,
#status {
  color: var(--muted);
  font-size: 0.86rem;
}

input,
select,
button,
textarea,
fieldset {
  border-radius: 8px;
}

input,
select,
button,
textarea {
  border: 1px solid var(--border);
  background: var(--panel-2);
  color: var(--text);
  padding: 8px;
}

input[readonly] {
  opacity: 0.9;
}

textarea {
  width: 100%;
  resize: vertical;
  min-height: 120px;
}

button {
  cursor: pointer;
  transition: border-color 0.2s ease, transform 0.05s ease;
}

button:hover {
  border-color: var(--accent);
}

button:active {
  transform: translateY(1px);
}

fieldset {
  border: 1px solid var(--border);
  padding: 10px;
  margin: 0 0 12px;
}

.help {
  margin: 6px 0 0;
  line-height: 1.3;
}

.workspace {
  display: grid;
  grid-template-rows: auto 1fr auto;
  gap: 12px;
}

.workspace-top {
  width: min(360px, 100%);
}

.image-compare {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.image-compare h3 {
  margin: 0 0 6px;
  font-size: 0.9rem;
  color: var(--muted);
}

.image-compare img {
  width: 100%;
  max-height: 160px;
  object-fit: contain;
  background: #0b0e13;
  border: 1px solid var(--border);
  border-radius: 8px;
}

.canvas-wrap {
  background: #0b0e13;
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 10px;
  overflow: auto;
  min-height: 300px;
}

#patternCanvas {
  image-rendering: pixelated;
  image-rendering: crisp-edges;
  display: block;
  background: #fff;
  border: 1px solid #303846;
  max-width: 100%;
  height: auto;
}

.palette-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
  gap: 8px;
  padding-top: 10px;
}

.palette-item {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.8rem;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 6px;
  background: var(--panel-2);
  text-align: left;
  width: 100%;
}

.palette-item.active {
  border-color: var(--accent);
  box-shadow: 0 0 0 1px #4da3ff66;
}

.swatch {
  width: 20px;
  height: 20px;
  border-radius: 5px;
  border: 1px solid #00000066;
  flex-shrink: 0;
}

#optimizeImageBtn.loading {
  position: relative;
  color: transparent;
}

#optimizeImageBtn.loading::after {
  content: "";
  position: absolute;
  width: 14px;
  height: 14px;
  border: 2px solid #9ea7b8;
  border-top-color: transparent;
  border-radius: 50%;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to {
    transform: translate(-50%, -50%) rotate(360deg);
  }
}

@media (max-width: 1024px) {
  .app {
    grid-template-columns: 1fr;
  }

  .workspace-top {
    width: 100%;
  }

  .image-compare {
    grid-template-columns: 1fr;
  }
}