:root {
  --primary: #1d4ed8;
  --primary-bg: #eff6ff;
  --border: #cbd5e1;
  --dark: #0f172a;
  --text: #1e293b;
  --muted: #64748b;
}

* {
  box-sizing: border-box;
  user-select: none;
}

body {
  margin: 0;
  padding: 0;
  font-family: 'Segoe UI', 'Hiragino Kaku Gothic ProN', 'Meiryo', sans-serif;
  background: #f1f5f9;
  color: var(--text);
  height: 100vh;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

header {
  background: var(--dark);
  color: white;
  padding: 6px 14px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  box-shadow: 0 2px 6px rgba(0,0,0,0.2);
  z-index: 10;
  flex-wrap: wrap;
  gap: 8px;
}

.brand {
  font-size: 15px;
  font-weight: bold;
  display: flex;
  align-items: center;
  gap: 9px;
}

.app-icon-svg {
  width: 30px;
  height: 30px;
  border-radius: 7px;
  box-shadow: 0 2px 5px rgba(0,0,0,0.35);
  flex-shrink: 0;
}

.spec-badge {
  background: #059669;
  color: white;
  font-size: 10.5px;
  padding: 2px 7px;
  border-radius: 4px;
  font-weight: 600;
}

.private-badge {
  background: #334155;
  color: #cbd5e1;
  font-size: 10px;
  padding: 2px 6px;
  border-radius: 4px;
  border: 1px solid #475569;
}

.cas-bar {
  display: flex;
  align-items: center;
  gap: 5px;
  background: #1e293b;
  padding: 3px 8px;
  border-radius: 6px;
  border: 1px solid #334155;
}

.cas-bar input {
  background: #ffffff;
  color: #0f172a;
  border: none;
  border-radius: 4px;
  padding: 4px 8px;
  font-size: 12px;
  width: 175px;
  outline: none;
  user-select: text;
}

.export-bar {
  display: flex;
  align-items: center;
  gap: 5px;
  background: #1e293b;
  padding: 4px 8px;
  border-radius: 6px;
  border: 1px solid #475569;
}

.export-bar select {
  background: #0f172a;
  color: #f8fafc;
  border: 1px solid #475569;
  border-radius: 4px;
  padding: 4px 6px;
  font-size: 11.5px;
  font-weight: bold;
  cursor: pointer;
  outline: none;
}

.workspace {
  display: grid;
  grid-template-columns: 305px 1fr 245px;
  gap: 10px;
  padding: 10px;
  flex: 1;
  overflow: hidden;
}

.panel {
  background: white;
  border: 1px solid var(--border);
  border-radius: 8px;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  box-shadow: 0 1px 3px rgba(0,0,0,0.05);
}

.panel-header {
  background: #f8fafc;
  padding: 8px 12px;
  font-size: 12.5px;
  font-weight: bold;
  border-bottom: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.panel-body {
  padding: 10px;
  overflow-y: auto;
  flex: 1;
}

.sec-label {
  font-size: 10.5px;
  font-weight: bold;
  color: var(--muted);
  margin: 10px 0 4px 0;
  text-transform: uppercase;
  letter-spacing: 0.3px;
}

.sec-label:first-child {
  margin-top: 0;
}

.tool-grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 4px; }
.tool-grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 4px; }
.tool-grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 4px; }

.t-btn {
  background: #f8fafc;
  border: 1px solid var(--border);
  border-radius: 5px;
  padding: 5px 3px;
  font-size: 12px;
  font-weight: 600;
  color: var(--text);
  cursor: pointer;
  text-align: center;
  transition: all 0.1s;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.t-btn:hover {
  border-color: var(--primary);
  background: #f1f5f9;
}

.t-btn.active {
  background: var(--primary-bg);
  border: 2px solid var(--primary);
  color: var(--primary);
  padding: 4px 2px;
}

.t-btn small {
  font-size: 9.5px;
  color: var(--muted);
  font-weight: normal;
  margin-top: 1px;
}

.t-btn.select-btn { background: #eff6ff; border-color: #93c5fd; color: #1e40af; }
.t-btn.select-btn.active { background: #dbeafe; border: 2px solid #1d4ed8; color: #1e3a8a; }
.t-btn.chain-btn { background: #ecfdf5; border-color: #6ee7b7; color: #065f46; }
.t-btn.chain-btn.active { background: #d1fae5; border: 2px solid #059669; color: #064e3b; }
.t-btn.mech-btn { background: #fdf4ff; border-color: #e9d5ff; color: #6b21a8; }
.t-btn.mech-btn.active { background: #f3e8ff; border: 2px solid #9333ea; color: #581c87; }

/* Center Canvas & Toolbars */
.canvas-panel {
  display: flex;
  flex-direction: column;
  background: white;
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
}

.canvas-toolbar {
  background: #f8fafc;
  border-bottom: 1px solid var(--border);
  padding: 5px 10px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
}

.align-toolbar {
  background: #f1f5f9;
  border-bottom: 1px solid var(--border);
  padding: 4px 10px;
  display: flex;
  align-items: center;
  gap: 5px;
  flex-wrap: wrap;
}

.toolbar-divider {
  width: 1px;
  height: 18px;
  background: #cbd5e1;
  margin: 0 3px;
}

.status-pill {
  background: #dbeafe;
  color: #1e40af;
  padding: 3px 9px;
  border-radius: 99px;
  font-size: 11.5px;
  font-weight: bold;
  display: flex;
  align-items: center;
  gap: 5px;
}

.svg-container {
  flex: 1;
  position: relative;
  background-color: #ffffff;
  background-image: radial-gradient(#cbd5e1 1px, transparent 1px);
  background-size: 18px 18px;
  overflow: hidden;
  cursor: default;
}

.svg-container.checkerboard {
  background-color: #ffffff;
  background-image:
    linear-gradient(45deg, #e2e8f0 25%, transparent 25%),
    linear-gradient(-45deg, #e2e8f0 25%, transparent 25%),
    linear-gradient(45deg, transparent 75%, #e2e8f0 75%),
    linear-gradient(-45deg, transparent 75%, #e2e8f0 75%);
  background-size: 20px 20px;
  background-position: 0 0, 0 10px, 10px -10px, -10px 0px;
}

#chem_svg {
  width: 100%;
  height: 100%;
  display: block;
}

.view-Controls-floating {
  position: absolute;
  bottom: 10px;
  right: 10px;
  background: rgba(255,255,255,0.92);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 4px 8px;
  display: flex;
  align-items: center;
  gap: 4px;
  box-shadow: 0 2px 6px rgba(0,0,0,0.08);
  font-size: 11px;
}

.canvas-footer {
  background: #f8fafc;
  border-top: 1px solid var(--border);
  padding: 7px 12px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.chem-info {
  display: flex;
  gap: 12px;
  font-size: 12px;
  align-items: center;
  flex-wrap: wrap;
}

.chem-info strong {
  color: var(--primary);
}

.btn {
  padding: 4px 8px;
  border-radius: 5px;
  border: 1px solid transparent;
  font-size: 11.5px;
  font-weight: bold;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 3px;
}

.btn-primary { background: var(--primary); color: white; }
.btn-success { background: #059669; color: white; }
.btn-purple { background: #7c3aed; color: white; }
.btn-cyan { background: #0284c7; color: white; }
.btn-outline { background: white; border-color: var(--border); color: var(--text); }
.btn-align { background: #ffffff; border-color: #94a3b8; color: #0f172a; }
.btn-align:hover { background: #eff6ff; border-color: var(--primary); color: var(--primary); }
.btn-danger { background: #dc2626; color: white; }
.btn:hover { opacity: 0.92; }

.stock-card {
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 8px;
  margin-bottom: 8px;
  background: #fafbfc;
}

.stock-thumb {
  background: white;
  border: 1px solid #e2e8f0;
  border-radius: 4px;
  height: 85px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  margin-bottom: 6px;
}

.stock-thumb svg {
  max-width: 100%;
  max-height: 80px;
}

/* Periodic Table Modal */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(15,23,42,0.6);
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 1000;
}

.modal-backdrop.open {
  display: flex;
}

.modal-box {
  background: white;
  border-radius: 10px;
  padding: 18px;
  max-width: 860px;
  width: 95%;
  box-shadow: 0 10px 25px rgba(0,0,0,0.25);
}

.ptable-grid {
  display: grid;
  grid-template-columns: repeat(18, 1fr);
  gap: 3px;
  margin-top: 10px;
}

.pt-cell {
  border: 1px solid #cbd5e1;
  border-radius: 3px;
  padding: 5px 2px;
  text-align: center;
  cursor: pointer;
  font-size: 11px;
  font-weight: bold;
  background: #f8fafc;
  transition: transform 0.1s;
}

.pt-cell:hover {
  transform: scale(1.15);
  z-index: 2;
  border-color: var(--primary);
  background: #dbeafe;
}

.pt-cell small {
  display: block;
  font-size: 8px;
  font-weight: normal;
  color: #64748b;
}

.pt-empty { pointer-events: none; }
.pt-nonmetal { background: #dcfce7; }
.pt-alkali { background: #fee2e2; }
.pt-transition { background: #fef3c7; }
.pt-halogen { background: #f3e8ff; }
.pt-noble { background: #e0f2fe; }

#toast {
  position: fixed;
  bottom: 16px;
  right: 16px;
  background: #0f172a;
  color: white;
  padding: 8px 14px;
  border-radius: 6px;
  font-size: 12.5px;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s;
  z-index: 2000;
}

#toast.show {
  opacity: 1;
}