:root {
  --bg: #0f1117;
  --surface: #1a1d27;
  --surface2: #242736;
  --border: #2e3247;
  --accent: #4f8ef7;
  --accent-hover: #6ba3ff;
  --accent-dim: rgba(79, 142, 247, 0.15);
  --text: #e4e6f0;
  --text-dim: #8a8fa8;
  --success: #34c97a;
  --danger: #f75252;
  --cell-size: 40px;
}

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

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Segoe UI', system-ui, sans-serif;
  min-height: 100vh;
  word-break: keep-all;
}

/* ═══════════════════════════════════════════════════════════
   INTRO PAGE
═══════════════════════════════════════════════════════════ */
#intro {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: radial-gradient(ellipse at 60% 40%, #1c2a4a 0%, #0f1117 60%);
  padding: 40px 20px;
}

.intro-content {
  text-align: center;
  max-width: 600px;
  animation: introFadeIn 0.5s ease both;
}

@keyframes introFadeIn {
  from { opacity: 0; }
  to   { opacity: 1; }
}

@keyframes introSlideUp {
  from { opacity: 0; transform: translateY(24px); }
  to   { opacity: 1; transform: translateY(0); }
}

@keyframes introBounce {
  0%   { opacity: 0; transform: scale(0.85); }
  60%  { opacity: 1; transform: scale(1.04); }
  100% { transform: scale(1); }
}

.anim-1 { animation: introSlideUp 0.5s 0.1s ease both; }
.anim-2 { animation: introSlideUp 0.5s 0.25s ease both; }
.anim-3 { animation: introSlideUp 0.5s 0.4s ease both; }
.anim-4 { animation: introSlideUp 0.5s 0.55s ease both; }
.anim-5 { animation: introSlideUp 0.5s 0.7s ease both; }
.anim-6 { animation: introSlideUp 0.5s 0.9s  ease both; }
.anim-7 { animation: introBounce  0.5s 1.05s ease both; }

.intro-badge {
  display: inline-block;
  background: var(--accent-dim);
  border: 1px solid var(--accent);
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.5px;
  padding: 4px 14px;
  border-radius: 20px;
  margin-bottom: 18px;
}

.intro-title {
  font-size: clamp(2.2rem, 6vw, 3.4rem);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -1px;
  margin-bottom: 16px;
  background: linear-gradient(135deg, #ffffff 30%, #4f8ef7);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.intro-desc {
  color: var(--text-dim);
  font-size: 1rem;
  line-height: 1.7;
  margin-bottom: 36px;
}

/* ── Intro Visual ─────────────────────────────────────── */
.intro-visual {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: clamp(6px, 2vw, 20px);
  margin-bottom: 36px;
}

.iv-wrap { display: flex; flex-direction: column; align-items: center; gap: 8px; }
.iv-label { font-size: 0.75rem; color: var(--text-dim); }

.iv-full {
  width: 120px;
  height: 90px;
  border-radius: 6px;
  background: linear-gradient(135deg, #4f8ef7 0%, #c97af7 50%, #f7834f 100%);
  position: relative;
  overflow: hidden;
}

.iv-grid-line {
  position: absolute;
  background: rgba(255,255,255,0.5);
}
.iv-v1 { left: 30px;  top: 0; width: 1px; height: 100%; }
.iv-v2 { left: 60px;  top: 0; width: 1px; height: 100%; }
.iv-v3 { left: 90px;  top: 0; width: 1px; height: 100%; }
.iv-h1 { top: 30px; left: 0; height: 1px; width: 100%; }
.iv-h2 { top: 60px; left: 0; height: 1px; width: 100%; }

.iv-tiles {
  display: grid;
  grid-template-columns: repeat(4, 28px);
  grid-template-rows: repeat(2, 28px);
  gap: 3px;
}
.iv-tile { border-radius: 4px; }
.iv-tile.wide { grid-column: span 2; }
.c1 { background: linear-gradient(135deg, #4f8ef7, #6ba3ff); }
.c2 { background: linear-gradient(135deg, #c97af7, #d49aff); }
.c3 { background: linear-gradient(135deg, #f7834f, #f9a070); }
.c4 { background: linear-gradient(135deg, #34c97a, #5adb99); }
.c5 { background: linear-gradient(135deg, #f7d24f, #f9df78); }

.iv-arrow { font-size: 1.5rem; color: var(--text-dim); }

/* ── Intro Demo Images ───────────────────────────────── */
.iv-demo-item { display: flex; flex-direction: column; align-items: center; gap: 8px; }
.iv-op { font-size: clamp(0.85rem, 2.4vw, 1.1rem); color: var(--text-dim); padding: 0 4px; align-self: center; }
.iv-demo-img { border-radius: 8px; object-fit: cover; display: block; }
.iv-demo-square { width: clamp(72px, 22vw, 160px); height: clamp(72px, 22vw, 160px); }
.iv-demo-phone  { width: clamp(54px, 16.4vw, 119px); height: clamp(72px, 22vw, 160px); }

/* ── Intro Steps ──────────────────────────────────────── */
.intro-steps {
  display: flex;
  justify-content: center;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 36px;
}

.intro-step {
  display: flex;
  align-items: center;
  gap: 8px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 8px 16px;
}
.is-num {
  width: 22px; height: 22px;
  background: var(--accent);
  color: #fff;
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 0.75rem;
  font-weight: 700;
  flex-shrink: 0;
}
.is-label { font-size: 0.85rem; color: var(--text-dim); white-space: nowrap; }

.btn-start {
  background: var(--accent);
  color: #fff;
  font-size: 1.1rem;
  font-weight: 700;
  padding: 14px 40px;
  border-radius: 12px;
  border: none;
  cursor: pointer;
  transition: background 0.15s, transform 0.1s;
  letter-spacing: 0.3px;
}
.btn-start:hover { background: var(--accent-hover); transform: scale(1.03); }
.btn-start:active { transform: scale(0.97); }

.intro-ver {
  font-size: 0.75rem;
  color: var(--text-dim);
  opacity: 0.6;
  margin-bottom: 6px;
}

.intro-credit {
  margin-top: 10px;
  margin-bottom: 20px;
  font-size: 0.78rem;
  color: var(--text-dim);
}
.intro-credit a {
  color: var(--text-dim);
  text-decoration: none;
  transition: color 0.15s;
}
.intro-credit a:hover { color: var(--text); }
.ic-github {
  width: 16px;
  height: 16px;
  vertical-align: -2px;
  display: inline-block;
}

/* ═══════════════════════════════════════════════════════════
   MAIN APP
═══════════════════════════════════════════════════════════ */
#app {
  max-width: 960px;
  margin: 0 auto;
  padding: 24px 16px 60px;
}

/* ── Header ─────────────────────────────────────────────── */
header {
  position: relative;
  text-align: center;
  margin-bottom: 32px;
}
header h1 { font-size: 2rem; font-weight: 700; letter-spacing: -0.5px; }
header .subtitle { color: var(--text-dim); margin-top: 6px; font-size: 0.95rem; }

/* ── Step Indicator ──────────────────────────────────────── */
.step-indicator {
  display: flex;
  align-items: center;
  justify-content: center;
  margin-top: 24px;
  gap: 0;
}
.step-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  opacity: 0.4;
  transition: opacity 0.2s;
  cursor: default;
}
.step-item.done  { opacity: 0.7; cursor: pointer; }
.step-item.active { opacity: 1; }
.step-item.done:hover .step-circle { border-color: var(--accent); }
.step-circle {
  width: 36px; height: 36px;
  border-radius: 50%;
  border: 2px solid var(--border);
  display: flex; align-items: center; justify-content: center;
  font-weight: 700; font-size: 0.9rem;
  background: var(--surface);
  transition: background 0.2s, border-color 0.2s;
}
.step-item.active .step-circle { background: var(--accent); border-color: var(--accent); }
.step-item.done .step-circle  { background: var(--success); border-color: var(--success); }
.step-item span { font-size: 0.75rem; color: var(--text-dim); white-space: nowrap; }
.step-item.active span { color: var(--text); }
.step-connector { width: 60px; height: 2px; background: var(--border); margin-bottom: 22px; flex-shrink: 1; min-width: 8px; }

@media (max-width: 600px) {
  .step-circle { width: 30px; height: 30px; font-size: 0.82rem; }
  .step-connector { width: 16px; margin-bottom: 19px; }
  .step-item { gap: 4px; }
  .step-item span { font-size: 0.68rem; }
}

/* ── Section ─────────────────────────────────────────────── */
.step-section { display: none; }
.step-section.active { display: block; }

.section-header { margin-bottom: 24px; }
.section-header h2 { font-size: 1.3rem; margin-bottom: 6px; }
.section-header p { color: var(--text-dim); font-size: 0.9rem; }

.sub-heading {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-dim);
  margin: 24px 0 12px;
  padding-bottom: 6px;
  border-bottom: 1px solid var(--border);
}

/* ── Buttons ─────────────────────────────────────────────── */
.btn {
  padding: 10px 20px;
  border-radius: 8px;
  border: none;
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s, opacity 0.15s, transform 0.1s;
  white-space: nowrap;
}
.btn:active { transform: scale(0.97); }
.btn:disabled { opacity: 0.35; cursor: not-allowed; transform: none; }

.btn-primary  { background: var(--accent); color: #fff; }
.btn-primary:hover:not(:disabled) { background: var(--accent-hover); }

.btn-danger   { background: rgba(247,82,79,0.15); color: var(--danger); border: 1px solid var(--danger); }
.btn-danger:hover { background: rgba(247,82,79,0.25); }

.btn-next     { background: var(--accent); color: #fff; }
.btn-next:hover:not(:disabled) { background: var(--accent-hover); }

.btn-back     { background: var(--surface2); color: var(--text); border: 1px solid var(--border); }
.btn-back:hover { background: var(--border); }

.btn-download { background: var(--success); color: #fff; font-size: 1rem; padding: 12px 28px; }
.btn-download:hover { filter: brightness(1.1); }

.btn-restart  { background: var(--surface2); color: var(--text-dim); border: 1px solid var(--border); margin-left: auto; }
.btn-restart:hover { color: var(--text); border-color: var(--text-dim); }

.step-nav {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 28px;
  flex-wrap: wrap;
}

@media (max-width: 480px) {
  .btn { padding: 10px 14px; font-size: 0.88rem; }
  .btn-download { padding: 12px 20px; }
  .btn-restart { margin-left: 0; }
}

/* ── Step 1: Layout Example ──────────────────────────────── */
.step1-example {
  margin-bottom: 24px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 16px;
}
.step1-eg-row {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 20px;
  margin-bottom: 12px;
}
.step1-eg-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}
.step1-eg-label {
  font-size: 0.72rem;
  color: var(--text-dim);
  white-space: nowrap;
}
.step1-eg-phone {
  height: 160px;
  width: auto;
  border-radius: 6px;
  border: 1px solid var(--border);
  display: block;
}
.step1-eg-arrow {
  font-size: 1.6rem;
  color: var(--text-dim);
  flex-shrink: 0;
}
.step1-eg-desc {
  font-size: 0.84rem;
  color: var(--text-dim);
  line-height: 1.6;
  text-align: center;
}
.step1-eg-desc strong { color: var(--accent); }

/* Mini grid */
.mini-grid-eg {
  display: grid;
  grid-template-columns: repeat(4, 28px);
  grid-template-rows: repeat(5, 28px);
  gap: 2px;
  background: var(--surface2);
  padding: 4px;
  border-radius: 6px;
  border: 1px solid var(--border);
}
.mg-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 2px;
  font-size: 0.6rem;
  font-weight: 800;
  color: rgba(255,255,255,0.9);
}
.mg-btn1 { grid-row: 1/2; grid-column: 1/3; border: 2px solid #22d3ee; background: rgba(34,211,238,0.15); }
.mg-btn4 { grid-row: 1/3; grid-column: 3/4; border: 2px solid #facc15; background: rgba(250,204,21,0.15); }
.mg-btn5 { grid-row: 1/3; grid-column: 4/5; border: 2px solid #a855f7; background: rgba(168,85,247,0.15); }
.mg-btn2 { grid-row: 2/3; grid-column: 1/2; border: 2px solid #f87171; background: rgba(248,113,113,0.15); }
.mg-btn3 { grid-row: 2/3; grid-column: 2/3; border: 2px solid #4ade80; background: rgba(74,222,128,0.15); }
.mg-btn6 { grid-row: 3/4; grid-column: 1/5; border: 2px solid #dc2626; background: rgba(220,38,38,0.15); }
.mg-btn7 { grid-row: 4/6; grid-column: 1/5; border: 2px solid #22d3ee; background: rgba(34,211,238,0.12); }

/* ── Step 1: Grid ────────────────────────────────────────── */
.grid-inputs {
  display: flex;
  align-items: flex-end;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 16px;
}
.grid-inputs label {
  display: flex;
  flex-direction: column;
  gap: 4px;
  font-size: 0.85rem;
  color: var(--text-dim);
}
.grid-inputs input[type="number"],
.grid-inputs select.num-dropdown {
  width: 80px;
  padding: 8px 12px;
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text);
  font-size: 1rem;
  text-align: center;
  outline: none;
  font-family: inherit;
}
.grid-inputs input[type="number"]:focus,
.grid-inputs select.num-dropdown:focus { border-color: var(--accent); }
.num-row { display: inline-flex; align-items: center; gap: 6px; }
.num-row .num-custom { width: 72px; }
.times-sign { font-size: 1.4rem; color: var(--text-dim); padding-bottom: 6px; }

.help-text {
  font-size: 0.85rem;
  color: var(--text-dim);
  margin-bottom: 12px;
  padding: 8px 12px;
  background: var(--accent-dim);
  border-radius: 6px;
  border-left: 3px solid var(--accent);
}

#gridContainer { overflow: auto; padding: 4px; }

.grid-table {
  display: grid;
  user-select: none;
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow: hidden;
  width: fit-content;
}

.grid-cell {
  width: var(--cell-size);
  height: var(--cell-size);
  border-right: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  cursor: crosshair;
  position: relative;
  transition: background 0.08s;
  touch-action: none;
}
.grid-cell.hover-preview { background: rgba(79,142,247,0.2) !important; }
.grid-cell.occupied { cursor: pointer; }

.cell-label {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-size: 0.8rem;
  font-weight: 700;
  pointer-events: none;
  text-shadow: 0 1px 2px rgba(0,0,0,0.8);
}

/* ── Step 2: Upload ──────────────────────────────────────── */
#dropZone {
  border: 2px dashed var(--border);
  border-radius: 12px;
  padding: 48px 24px;
  text-align: center;
  cursor: pointer;
  transition: border-color 0.2s, background 0.2s;
  background: var(--surface);
}
#dropZone:hover, #dropZone.drag-over {
  border-color: var(--accent);
  background: var(--accent-dim);
}
.drop-icon { font-size: 3rem; margin-bottom: 12px; }
#dropZone p { color: var(--text-dim); margin-bottom: 16px; }
.upload-actions { display: flex; align-items: center; justify-content: center; gap: 16px; }
.or-text { color: var(--text-dim); font-size: 0.85rem; }

#previewContainer { margin-top: 20px; text-align: center; }
#previewImg {
  max-width: 100%;
  max-height: 300px;
  border-radius: 8px;
  border: 1px solid var(--border);
}

/* ── Step 3: Crop ────────────────────────────────────────── */
#cropWrapper {
  display: flex;
  justify-content: center;
  overflow: auto;
  background: var(--surface);
  border-radius: 8px;
  padding: 12px;
}
#cropCanvas {
  display: block;
  cursor: crosshair;
  border-radius: 4px;
  touch-action: none;
}

/* ── Step 4: Layout Preview ──────────────────────────────── */
#layoutPreviewWrap { margin-bottom: 8px; }

#layoutPreviewContainer {
  display: flex;
  justify-content: flex-start;
  overflow: auto;
}
#layoutPreviewContainer canvas {
  border: 1px solid var(--border);
  border-radius: 6px;
  display: block;
}

/* ── Step 4: Tile Type ───────────────────────────────────── */
#tileTypeSection { margin-top: 4px; }

.tt-desc {
  font-size: 0.85rem;
  color: var(--text-dim);
  line-height: 1.6;
  margin-bottom: 16px;
  padding: 10px 14px;
  background: rgba(247,210,79,0.07);
  border-radius: 6px;
  border-left: 3px solid #f7d24f;
}
.tt-desc strong { color: #f7d24f; }
.tt-desc code { font-family: monospace; background: rgba(255,255,255,0.07); padding: 1px 5px; border-radius: 3px; font-size: 0.82rem; }

.tt-warn {
  font-size: 0.84rem;
  color: #f7c46a;
  line-height: 1.55;
  background: rgba(247, 131, 79, 0.08);
  padding: 9px 12px;
  border-radius: 6px;
  border-left: 3px solid #f7834f;
  margin-bottom: 16px;
}
.tt-warn strong { color: #f7834f; }

#tileTypeGrid {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.tt-card {
  background: var(--surface);
  border: 2px solid var(--border);
  border-radius: 10px;
  padding: 10px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  width: 100px;
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s;
  user-select: none;
}
.tt-card:hover {
  border-color: var(--accent);
  background: var(--accent-dim);
}
.tt-card.special {
  border-color: var(--success);
  background: rgba(52,201,122,0.08);
}
.tt-card.special:hover {
  border-color: var(--success);
  background: rgba(52,201,122,0.16);
}
.tt-card canvas {
  border-radius: 4px;
  display: block;
  background-image: linear-gradient(45deg, #1e2030 25%, transparent 25%),
                    linear-gradient(-45deg, #1e2030 25%, transparent 25%),
                    linear-gradient(45deg, transparent 75%, #1e2030 75%),
                    linear-gradient(-45deg, transparent 75%, #1e2030 75%);
  background-size: 12px 12px;
  background-position: 0 0, 0 6px, 6px -6px, -6px 0px;
}
.tt-num {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--text-dim);
}
.tt-card.special .tt-num { color: var(--success); }

/* ═══════════════════════════════════════════════════════════
   LANGUAGE SELECTOR
═══════════════════════════════════════════════════════════ */
.lang-menu {
  position: absolute;
  top: 16px;
  right: 16px;
  z-index: 100;
}
.lang-trigger {
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 6px 10px;
  border-radius: 8px;
  font-size: 0.85rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 6px;
  line-height: 1;
}
.lang-trigger:hover { background: var(--surface2); }
.lang-caret { font-size: 0.7rem; opacity: 0.7; }
.lang-list {
  display: none;
  position: absolute;
  top: calc(100% + 4px);
  right: 0;
  min-width: 130px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 4px;
  list-style: none;
  margin: 0;
  box-shadow: 0 6px 18px rgba(0,0,0,0.35);
}
.lang-menu.open .lang-list { display: block; }
.lang-list li { margin: 0; }
.lang-option {
  width: 100%;
  text-align: left;
  background: transparent;
  border: 0;
  color: var(--text);
  padding: 8px 10px;
  border-radius: 6px;
  font-size: 0.85rem;
  cursor: pointer;
}
.lang-option:hover { background: var(--surface2); }
.lang-option.active { color: var(--accent); font-weight: 700; }

/* ═══════════════════════════════════════════════════════════
   STEP 4 — AFTER DOWNLOAD NOTE
═══════════════════════════════════════════════════════════ */
.after-download-note {
  margin-top: 24px;
  padding: 14px 16px;
  background: var(--accent-dim);
  border-left: 3px solid var(--accent);
  border-radius: 6px;
}
.after-download-note .ad-heading {
  margin: 0 0 6px 0;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--accent);
}
.after-download-note .ad-body {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.6;
  color: var(--text);
}
.after-download-note .ad-body strong {
  color: var(--accent);
  font-weight: 700;
}