/* ═══════════════════════════════════════════
   ui.css – Header, Buttons, Panels, Controls
   ═══════════════════════════════════════════ */

/* ── Header ── */
.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: .75rem 1.25rem;
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 100;
  gap: .75rem;
  flex-wrap: wrap;
}

.app-title {
  font-size: 1.25rem;
  font-weight: 700;
  white-space: nowrap;
  background: linear-gradient(135deg, var(--color-accent), #a78bfa);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.header-nav {
  display: flex;
  gap: .5rem;
  flex-wrap: wrap;
  align-items: center;
}

/* ── Buttons ── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: .35rem;
  padding: .45rem .9rem;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  font-size: .875rem;
  font-weight: 500;
  font-family: inherit;
  cursor: pointer;
  transition: background var(--transition), border-color var(--transition), transform 80ms;
  white-space: nowrap;
  line-height: 1.2;
  user-select: none;
}

.btn:active { transform: scale(.97); }

.btn-primary {
  background: var(--color-accent);
  color: #fff;
  border-color: var(--color-accent);
}
.btn-primary:hover { background: var(--color-accent-h); border-color: var(--color-accent-h); }

.btn-secondary {
  background: var(--color-secondary);
  color: var(--color-text);
  border-color: var(--color-secondary);
}
.btn-secondary:hover { background: #4d5a96; }

.btn-accent {
  background: linear-gradient(135deg, var(--color-accent), #a78bfa);
  color: #fff;
  border: none;
  font-weight: 600;
}
.btn-accent:hover { opacity: .9; }

.btn-ghost {
  background: transparent;
  color: var(--color-text-muted);
  border-color: var(--color-border);
}
.btn-ghost:hover { background: var(--color-surface2); color: var(--color-text); }

.btn-danger {
  background: var(--color-danger);
  color: #fff;
  border-color: var(--color-danger);
}
.btn-danger:hover { background: #f05e8a; }

.btn-full { width: 100%; justify-content: center; }
.btn-sm { padding: .3rem .65rem; font-size: .8rem; }
.btn-icon { padding: .3rem .5rem; }

.btn.active {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: #fff;
}

/* ── Grid size buttons ── */
.grid-size-btns {
  display: flex;
  gap: .35rem;
}

.grid-size-btn {
  background: var(--color-surface2);
  color: var(--color-text-muted);
  border-color: var(--color-border);
}
.grid-size-btn:hover { background: var(--color-secondary); color: var(--color-text); }
.grid-size-btn.active {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: #fff;
}

.control-label {
  font-size: .875rem;
  color: var(--color-text-muted);
}

/* ── Face Panel ── */
.face-panel {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 1rem 1.1rem;
  min-width: 230px;
  max-width: 270px;
  box-shadow: var(--shadow-md);
}

.face-panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: .85rem;
}

.face-label {
  font-size: 1rem;
  font-weight: 700;
  color: var(--color-text);
}

.face-section {
  margin-bottom: .85rem;
}

.section-label {
  display: block;
  font-size: .75rem;
  font-weight: 600;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: .06em;
  margin-bottom: .4rem;
}

/* ── Color Palette ── */
.color-palette {
  display: flex;
  flex-direction: column;
  gap: .35rem;
  margin-bottom: .5rem;
}

.palette-row {
  display: flex;
  align-items: center;
  gap: .3rem;
  flex-wrap: wrap;
}

.palette-swatch {
  width: 26px;
  height: 26px;
  border-radius: var(--radius-sm);
  border: 2px solid transparent;
  cursor: pointer;
  transition: transform var(--transition), border-color var(--transition);
  flex-shrink: 0;
  outline: 1px solid rgba(255,255,255,.15);
}
.palette-swatch:hover { transform: scale(1.18); }
.palette-swatch.active { border-color: #fff; outline-color: #fff; }

.palette-main {
  width: 30px;
  height: 30px;
  border-radius: var(--radius-sm);
}

.palette-expand {
  background: var(--color-surface2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  color: var(--color-text-muted);
  font-size: .9rem;
  width: 22px;
  height: 22px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  line-height: 1;
  padding: 0;
  transition: background var(--transition);
}
.palette-expand:hover { background: var(--color-secondary); color: var(--color-text); }

.palette-shades {
  display: none;
  gap: .3rem;
  flex-wrap: wrap;
}
.palette-shades.open { display: flex; }

.palette-shade {
  width: 24px;
  height: 24px;
}

.color-picker-input {
  width: 100%;
  height: 36px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-surface2);
  cursor: pointer;
  padding: 2px 4px;
}

.triangle-targets {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: .35rem;
}

.triangle-target-btn {
  justify-content: flex-start;
  background: var(--color-surface2);
  border-color: var(--color-border);
  color: var(--color-text);
  padding: .42rem .55rem;
  font-size: .75rem;
}

.triangle-target-btn:hover {
  background: var(--color-secondary);
}

.triangle-target-btn.active {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: #fff;
}

.triangle-target-btn:disabled {
  opacity: .5;
  cursor: not-allowed;
}

.triangle-target-hint {
  margin-top: .45rem;
  font-size: .68rem;
  color: var(--color-text-muted);
}

.triangle-legend {
  margin-top: .55rem;
  border: 1px dashed var(--color-border);
  border-radius: var(--radius-sm);
  padding: .45rem .5rem;
  display: flex;
  flex-direction: column;
  gap: .35rem;
  background: rgba(255,255,255,.02);
}

.triangle-legend-item {
  display: flex;
  align-items: flex-start;
  gap: .4rem;
}

.triangle-chip {
  width: 11px;
  height: 11px;
  border-radius: 2px;
  border: 1px solid rgba(255,255,255,.35);
  background: #ffffff;
  flex-shrink: 0;
  margin-top: .12rem;
}

.triangle-chip--secondary {
  border-style: dashed;
}

.triangle-legend-text {
  font-size: .7rem;
  color: var(--color-text-muted);
  line-height: 1.35;
}

/* ── Shape Buttons ── */
.shape-buttons {
  display: flex;
  flex-direction: column;
  gap: .35rem;
}

.shape-btn {
  background: var(--color-surface2);
  border-color: var(--color-border);
  color: var(--color-text);
  justify-content: flex-start;
  padding: .5rem .75rem;
}
.shape-btn:hover { background: var(--color-secondary); }
.shape-btn.active {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: #fff;
}
.shape-btn svg { flex-shrink: 0; }

/* ── Face preview ── */
.face-preview-wrap {
  display: flex;
  justify-content: center;
  padding-top: .25rem;
}

#face-preview-canvas {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
}

/* ── Faces Overview ── */
.faces-overview {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 1rem;
}

.overview-label {
  font-size: .75rem;
  font-weight: 600;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: .06em;
  display: block;
  margin-bottom: .65rem;
}

.faces-mini-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: .45rem;
}

.face-mini {
  cursor: pointer;
  border-radius: var(--radius-sm);
  border: 2px solid var(--color-border);
  overflow: hidden;
  aspect-ratio: 1;
  transition: border-color var(--transition);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: .2rem;
  padding: .3rem;
  background: var(--color-surface2);
}
.face-mini:hover { border-color: var(--color-accent); }
.face-mini.active { border-color: var(--color-accent); }
.face-mini canvas { display: block; }
.face-mini-label {
  font-size: .65rem;
  color: var(--color-text-muted);
  text-align: center;
  line-height: 1.2;
}

/* ── Cell Panel ── */
.cell-panel {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: .85rem;
  min-width: 200px;
  max-width: 240px;
  box-shadow: var(--shadow-md);
  flex-shrink: 0;
  align-self: flex-start;
  position: sticky;
  top: 5rem;
}

.cell-panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: .7rem;
}

.cell-panel-title {
  font-weight: 700;
  font-size: .9rem;
}

.cell-section {
  margin-bottom: .7rem;
}

.face-select-btns {
  display: flex;
  flex-wrap: wrap;
  gap: .4rem;
}

.face-select-btn {
  background: var(--color-surface2);
  border-color: var(--color-border);
  color: var(--color-text-muted);
  padding: .25rem .3rem;
  flex-direction: column;
  align-items: center;
  gap: .15rem;
  min-width: 44px;
}
.face-select-btn canvas {
  display: block;
  border-radius: 3px;
  pointer-events: none;
}
.face-select-num {
  font-size: .65rem;
  line-height: 1;
  pointer-events: none;
}
.face-select-btn:hover { background: var(--color-secondary); color: var(--color-text); }
.face-select-btn.active {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: #fff;
  outline: 2px solid var(--color-accent-h);
}

.rotation-btns {
  display: flex;
  gap: .3rem;
  flex-wrap: wrap;
}

.rot-btn {
  background: var(--color-surface2);
  border-color: var(--color-border);
  color: var(--color-text-muted);
  padding: .3rem .55rem;
  font-size: .8rem;
}
.rot-btn:hover { background: var(--color-secondary); color: var(--color-text); }
.rot-btn.active {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: #fff;
}

.cell-actions {
  display: flex;
  gap: .5rem;
  margin-top: .25rem;
}

/* ── Archive Item ── */
.archive-item {
  display: flex;
  align-items: center;
  gap: .6rem;
  padding: .65rem .75rem;
  border-radius: var(--radius-md);
  background: var(--color-surface2);
  border: 1px solid var(--color-border);
  margin-bottom: .5rem;
  transition: border-color var(--transition);
}
.archive-item:hover { border-color: var(--color-accent); }

.archive-item-info {
  flex: 1;
  min-width: 0;
}
.archive-item-name {
  font-weight: 600;
  font-size: .9rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.archive-item-meta {
  font-size: .75rem;
  color: var(--color-text-muted);
}

.archive-item-actions {
  display: flex;
  gap: .3rem;
  flex-shrink: 0;
}

.archive-search {
  width: 100%;
  background: var(--color-surface2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: .5rem .75rem;
  color: var(--color-text);
  font-size: .875rem;
  font-family: inherit;
  margin-bottom: .85rem;
  outline: none;
  transition: border-color var(--transition);
}
.archive-search:focus { border-color: var(--color-accent); }

.archive-list {
  max-height: 400px;
  overflow-y: auto;
  padding-right: .25rem;
}

.archive-empty {
  color: var(--color-text-muted);
  text-align: center;
  padding: 2rem 0;
  font-size: .9rem;
}

/* ── Responsive: iPad and below ── */
@media (max-width: 768px) {
  .app-title { font-size: 1.05rem; }

  .header-nav {
    gap: .35rem;
    justify-content: flex-start;
    width: 100%;
  }

  .header-nav .btn {
    font-size: .78rem;
    padding: .38rem .65rem;
  }

  .face-panel {
    min-width: 0;
    width: 100%;
  }
}

@media (max-width: 480px) {
  .app-title { font-size: .95rem; }

  .header-nav .btn {
    font-size: .72rem;
    padding: .32rem .5rem;
  }

  .face-select-btn {
    min-width: 38px;
  }

  .face-select-btn canvas {
    width: 26px !important;
    height: 26px !important;
  }
}