/* ─── Reset & Custom Properties ─────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg:           #141416;
  --surface:      #1F1F21;
  --surface-hi:   #252527;
  --border:       #2a2a2d;
  --border-hi:    #3a3a3e;
  --accent:       #E3FC02;
  --accent-dim:   rgba(227, 252, 2, 0.08);
  --accent-glow:  rgba(227, 252, 2, 0.18);
  --text:         #efefef;
  --muted:        #636366;
  --muted-hi:     #959598;
  --error:        #ff4b4b;
  --fsa:          #00c8ff;
  --fsa-dim:      rgba(0, 200, 255, 0.09);
  --font-mono:    'Space Mono', monospace;
  --font-sans:    'DM Sans', sans-serif;
  --radius:       12px;
  --radius-sm:    8px;
  --t:            140ms ease;
  --shadow:       0 4px 28px rgba(0,0,0,0.55);
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 15px;
  line-height: 1.5;
  min-height: 100vh;
  background-image:
    radial-gradient(ellipse 80% 40% at 50% -8%, rgba(227,252,2,0.022) 0%, transparent 60%);
}

/* ─── Layout ─────────────────────────────────────────────────────────────── */
.app {
  max-width: 1200px;
  margin: 0 auto;
  padding: clamp(20px, 4vw, 48px) clamp(16px, 3vw, 32px);
}

/* ─── Header ─────────────────────────────────────────────────────────────── */
.header { margin-bottom: 26px; }

.header-label {
  font-family: var(--font-mono);
  font-size: 9px;
  letter-spacing: 0.22em;
  color: var(--accent);
  opacity: 0.65;
  margin-bottom: 10px;
}

h1 {
  font-family: var(--font-mono);
  font-size: clamp(21px, 3.2vw, 34px);
  font-weight: 700;
  color: #fff;
  display: flex;
  align-items: center;
  gap: 14px;
  line-height: 1.15;
  letter-spacing: -0.015em;
}

.badge {
  font-family: var(--font-mono);
  font-size: 11px;
  background: var(--accent);
  color: #000;
  padding: 3px 10px;
  border-radius: 4px;
  letter-spacing: 0.08em;
  font-weight: 700;
}

.sub {
  color: var(--muted);
  font-size: 12px;
  margin-top: 7px;
  letter-spacing: 0.01em;
}

/* ─── Panel ──────────────────────────────────────────────────────────────── */
.panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: clamp(14px, 2.5vw, 22px) clamp(14px, 2.5vw, 24px);
  margin-bottom: 18px;
  box-shadow: var(--shadow);
}

/* ─── Progress bar ───────────────────────────────────────────────────────── */
.progress-bar {
  height: 2px;
  background: var(--border);
  border-radius: 2px;
  margin-bottom: 14px;
  opacity: 0;
  transition: opacity 200ms ease;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--accent), rgba(227,252,2,0.6));
  border-radius: 2px;
  transition: width 220ms ease;
  box-shadow: 0 0 7px var(--accent-glow);
}

/* ─── Status row ─────────────────────────────────────────────────────────── */
.status-row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 14px;
  min-height: 20px;
}

.model-dot {
  flex-shrink: 0;
  width: 7px;
  height: 7px;
  border-radius: 50%;
}

.model-dot--loading {
  background: #3a3a3e;
  animation: dot-pulse 1.6s ease-in-out infinite;
}

.model-dot--ready {
  background: var(--accent);
  box-shadow: 0 0 0 3px rgba(227,252,2,0.18);
  animation: none;
}

@keyframes dot-pulse {
  0%, 100% { opacity: 0.22; transform: scale(0.75); }
  50%       { opacity: 1;    transform: scale(1.15); }
}

.status {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--muted-hi);
  flex: 1;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  transition: color var(--t);
}

.status-error { color: var(--error); }

/* ─── Buttons ────────────────────────────────────────────────────────────── */
.controls {
  display: flex;
  gap: 9px;
  flex-wrap: wrap;
  align-items: center;
  margin-bottom: 18px;
}

button {
  font-family: var(--font-sans);
  font-size: 13px;
  font-weight: 600;
  border: none;
  padding: 9px 20px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  background: var(--accent);
  color: #000;
  transition: opacity var(--t), transform var(--t), box-shadow var(--t);
  letter-spacing: 0.01em;
  white-space: nowrap;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  line-height: 1;
}

button:hover:not(:disabled) {
  opacity: 0.88;
  transform: translateY(-1px);
  box-shadow: 0 4px 18px var(--accent-glow);
}
button:active:not(:disabled) { transform: translateY(0); box-shadow: none; }
button:disabled {
  background: var(--border);
  color: var(--muted);
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

.btn-secondary {
  background: transparent;
  color: var(--text);
  border: 1px solid var(--border-hi);
}
.btn-secondary:hover:not(:disabled) {
  border-color: var(--accent);
  color: var(--accent);
  box-shadow: none;
}
.btn-secondary:disabled { border-color: var(--border); color: var(--muted); }

.btn-danger {
  background: transparent;
  color: var(--error);
  border: 1px solid rgba(255,75,75,0.22);
}
.btn-danger:hover:not(:disabled) { background: rgba(255,75,75,0.07); box-shadow: none; }

/* FSA button */
.btn-fsa {
  background: transparent;
  color: var(--fsa);
  border: 1px solid rgba(0,200,255,0.28);
}
.btn-fsa:hover:not(:disabled) {
  background: var(--fsa-dim);
  border-color: var(--fsa);
  box-shadow: 0 0 14px rgba(0,200,255,0.10);
}
.btn-fsa:disabled { border-color: var(--border); color: var(--muted); }

/* Star indicator when FSA is recommended for large image */
.btn-fsa-recommended {
  border-color: var(--fsa);
  background: rgba(0,200,255,0.05);
  position: relative;
}
.btn-fsa-recommended::after {
  content: "✦";
  position: absolute;
  top: -5px;
  right: -5px;
  font-size: 7px;
  background: var(--fsa);
  color: #000;
  width: 13px;
  height: 13px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  line-height: 1;
}

/* ─── Metrics grid ───────────────────────────────────────────────────────── */
/*
 * A responsive grid of live stats refreshed every 400ms during processing.
 * Each cell shows one metric (workers, speed, tiles, eta, backend, etc).
 * Uses CSS grid with auto-fit for graceful mobile collapse.
 */
.metrics-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(110px, 1fr));
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.metric-cell {
  background: var(--surface-hi);
  padding: 9px 12px;
  display: flex;
  flex-direction: column;
  gap: 3px;
  transition: background var(--t);
}

.metric-cell--wide {
  grid-column: span 2;
}

.metric-label {
  font-family: var(--font-mono);
  font-size: 8.5px;
  color: var(--muted);
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.metric-value {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--muted-hi);
  letter-spacing: 0.03em;
  transition: color var(--t);
  line-height: 1.3;
}

/* Highlight active workers metric during processing */
.panel.processing .metric-cell:first-child .metric-value {
  color: var(--accent);
}

/* ─── Workspace ──────────────────────────────────────────────────────────── */
.workspace {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.box {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
  box-shadow: var(--shadow);
}

.box-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
  gap: 8px;
}

.box-header-meta {
  display: flex;
  align-items: center;
  gap: 10px;
}

h2 {
  font-family: var(--font-mono);
  font-size: 9.5px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--muted);
}

.img-info {
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--accent);
  opacity: 0.7;
  white-space: nowrap;
}

.preview-tag {
  font-family: var(--font-mono);
  font-size: 8.5px;
  color: var(--muted);
  background: rgba(255,255,255,0.04);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 2px 7px;
  letter-spacing: 0.06em;
  white-space: nowrap;
}

/* ─── Preview wrap ───────────────────────────────────────────────────────── */
.preview-wrap {
  border: 1.5px dashed var(--border);
  min-height: 340px;
  border-radius: 10px;
  overflow: hidden;
  background: #0c0c0e;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  transition: border-color var(--t);
}

/* ─── Drop zone ──────────────────────────────────────────────────────────── */
.drop-zone {
  cursor: pointer;
  transition: border-color var(--t), background var(--t);
}
.drop-zone:hover { border-color: var(--accent); background: var(--accent-dim); }
.drop-zone.drag-over {
  border-color: var(--accent);
  background: var(--accent-dim);
  border-style: solid;
}

.drop-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 7px;
  padding: 30px 20px;
  text-align: center;
  pointer-events: none;
}

.drop-icon {
  width: 36px;
  height: 36px;
  color: var(--muted);
  margin-bottom: 4px;
  opacity: 0.55;
}

.drop-label {
  font-size: 13px;
  color: var(--text);
  font-weight: 500;
}

.drop-sub  { font-size: 12px; color: var(--muted); }

.drop-hint {
  font-family: var(--font-mono);
  font-size: 9px;
  color: #333336;
  letter-spacing: 0.07em;
  margin-top: 4px;
}

.link-btn {
  color: var(--accent);
  cursor: pointer;
  pointer-events: all;
  text-decoration: underline;
  text-underline-offset: 2px;
}

#originalPreview {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: none;
}

.change-img-btn {
  position: absolute;
  bottom: 10px;
  right: 10px;
  font-size: 9px;
  font-family: var(--font-mono);
  padding: 5px 10px;
  background: rgba(20,20,22,0.86);
  color: var(--accent);
  border: 1px solid rgba(227,252,2,0.3);
  border-radius: 6px;
  cursor: pointer;
  display: none;
  backdrop-filter: blur(6px);
  letter-spacing: 0.07em;
  z-index: 2;
}
.change-img-btn:hover { background: var(--accent-dim); transform: none; box-shadow: none; }

/* Has-image states */
.drop-zone.has-image .drop-inner      { display: none; }
.drop-zone.has-image #originalPreview { display: block; }
.drop-zone.has-image .change-img-btn  { display: block; }
.drop-zone.has-image { cursor: default; border-style: solid; border-color: var(--border); }

/* ─── Preview canvas ─────────────────────────────────────────────────────── */
#previewCanvas {
  max-width: 100%;
  max-height: 440px;
  display: none;
  border-radius: 6px;
  image-rendering: crisp-edges;
  image-rendering: -webkit-optimize-contrast;
}

/* Result placeholder */
#resultPlaceholder { display: flex; flex-direction: column; align-items: center; gap: 6px; }

/* ─── Shake animation (size rejection) ──────────────────────────────────── */
@keyframes shake {
  0%, 100% { transform: translateX(0); }
  20%       { transform: translateX(-7px); }
  40%       { transform: translateX(7px); }
  60%       { transform: translateX(-4px); }
  80%       { transform: translateX(4px); }
}
.drop-zone.shake {
  animation: shake 0.4s ease;
  border-color: var(--error) !important;
}

/* ─── Responsive ─────────────────────────────────────────────────────────── */
@media (max-width: 780px) {
  .workspace { grid-template-columns: 1fr; }
  .controls  { flex-direction: column; }
  button     { width: 100%; text-align: center; justify-content: center; }
  .metrics-grid { grid-template-columns: repeat(2, 1fr); }
  .metric-cell--wide { grid-column: span 2; }
}

@media (max-width: 480px) {
  h1 { font-size: 19px; }
  .preview-wrap { min-height: 220px; }
  #previewCanvas { max-height: 280px; }
  .metrics-grid { grid-template-columns: 1fr 1fr; }
}