/* ============================================================
   Bloch Sphere Visualizer — style.css
   Dark-mode quantum computing aesthetic
   ============================================================ */

/* ── Design tokens ───────────────────────────────────────── */
:root {
  --bg:          #0d1117;
  --bg-panel:    #161b24;
  --bg-card:     #1e2430;
  --bg-card2:    #252d3a;
  --text:        #e2e0da;
  --text-muted:  #8a8d88;
  --text-faint:  #4a4e4a;
  --accent:      #7a9e7e;
  --accent-hi:   #a8c5ab;
  --accent-glow: rgba(122,158,126,0.22);
  --accent-dim:  rgba(122,158,126,0.12);
  --border:      rgba(122,158,126,0.18);
  --border-hi:   rgba(122,158,126,0.38);
  --red:         #e6584d;
  --blue:        #4d8de6;
  --amber:       #e6a84d;
  --violet:      #8b5cf6;
  --cyan:        #06b6d4;
  --pink:        #ec4899;
  --font-mono:   'JetBrains Mono', 'Fira Code', monospace;
  --font-sans:   'DM Sans', system-ui, sans-serif;
  --font-serif:  'Cormorant Garamond', Georgia, serif;
  --nav-h:       52px;
  --circuit-h:   190px;
  --sidebar-w:   288px;
  --radius:      5px;
  --transition:  0.22s ease;
}

/* ── Reset ───────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; }
body {
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--text);
  height: 100vh;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}
button { cursor: pointer; font-family: inherit; }
input  { font-family: inherit; }

/* ── Navbar ──────────────────────────────────────────────── */
.navbar {
  height: var(--nav-h);
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 1.5rem;
  background: var(--bg-panel);
  border-bottom: 1px solid var(--border);
  z-index: 50;
  gap: 1rem;
}

.navbar__left {
  display: flex;
  align-items: center;
  gap: 0.65rem;
}

.navbar__icon {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
}

.navbar__titles {
  display: flex;
  flex-direction: column;
  gap: 1px;
}

.navbar__name {
  font-family: var(--font-serif);
  font-size: 1.05rem;
  font-weight: 500;
  color: var(--text);
  letter-spacing: 0.01em;
  line-height: 1.2;
}

.navbar__sub {
  font-size: 0.62rem;
  font-weight: 300;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.navbar__right {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.qubit-count {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text-muted);
  letter-spacing: 0.05em;
}

.btn-add {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.44rem 1rem;
  background: var(--accent);
  color: var(--bg);
  border: none;
  border-radius: 20px;
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.06em;
  transition: background var(--transition), opacity var(--transition), transform var(--transition);
}
.btn-add:hover { background: var(--accent-hi); transform: translateY(-1px); }
.btn-add:disabled { background: var(--text-faint); cursor: not-allowed; transform: none; opacity: 0.6; }

/* ── Workspace layout ─────────────────────────────────────── */
.workspace {
  flex: 1;
  display: flex;
  min-height: 0;
  overflow: hidden;
}

/* ── Sphere container ─────────────────────────────────────── */
.sphere-wrap {
  flex: 1;
  position: relative;
  min-width: 0;
  background: var(--bg);
  overflow: hidden;
}

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

/* Label overlay */
.label-overlay {
  position: absolute;
  inset: 0;
  pointer-events: none;
  overflow: hidden;
}

/* Pole labels */
.pole-label {
  position: absolute;
  transform: translate(-50%, -50%);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 400;
  color: var(--text-muted);
  background: rgba(13, 17, 23, 0.72);
  padding: 2px 6px;
  border-radius: 3px;
  border: 1px solid var(--border);
  white-space: nowrap;
  pointer-events: none;
  letter-spacing: 0.03em;
  backdrop-filter: blur(4px);
}

/* Qubit labels on sphere */
.qubit-label {
  position: absolute;
  transform: translate(-50%, -130%);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  padding: 2px 7px;
  border-radius: 3px;
  border: 1px solid;
  pointer-events: none;
  white-space: nowrap;
  backdrop-filter: blur(4px);
  background: rgba(13, 17, 23, 0.78);
  transition: opacity 0.2s ease;
}

/* Scale legend (axis gizmo) */
.scale-legend {
  position: absolute;
  bottom: 14px;
  right: 14px;
  width: 72px;
  height: 72px;
  background: rgba(22, 27, 36, 0.72);
  border: 1px solid var(--border);
  border-radius: 6px;
  backdrop-filter: blur(6px);
  overflow: hidden;
}
#legendCanvas { display: block; }

/* Entanglement warning */
.ent-warning {
  position: absolute;
  bottom: 14px;
  left: 14px;
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.68rem;
  font-weight: 400;
  color: var(--amber);
  background: rgba(22, 27, 36, 0.85);
  border: 1px solid rgba(230, 168, 77, 0.3);
  padding: 5px 10px;
  border-radius: 4px;
  backdrop-filter: blur(4px);
  opacity: 0;
  transform: translateY(6px);
  transition: opacity 0.3s ease, transform 0.3s ease;
  pointer-events: none;
}
.ent-warning.show {
  opacity: 1;
  transform: translateY(0);
}

/* Sphere empty hint */
.sphere-hint {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  pointer-events: none;
  transition: opacity 0.4s ease;
}
.sphere-hint.hidden { opacity: 0; }
.sphere-hint__inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.75rem;
  color: var(--text-faint);
  text-align: center;
}
.sphere-hint__inner p {
  font-size: 0.82rem;
  font-weight: 300;
  line-height: 1.6;
  color: var(--text-muted);
}
.sphere-hint__inner strong { color: var(--accent); font-weight: 500; }

/* ── Sidebar ─────────────────────────────────────────────── */
.sidebar {
  width: var(--sidebar-w);
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  background: var(--bg-panel);
  border-left: 1px solid var(--border);
  overflow-y: auto;
  overflow-x: hidden;
}

/* Panel */
.panel {
  padding: 1rem 1.1rem;
  border-bottom: 1px solid var(--border);
}
.panel__hdr {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.85rem;
}
.panel__label {
  font-size: 0.63rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
}
.panel__hint {
  font-size: 0.62rem;
  color: var(--text-faint);
  letter-spacing: 0.04em;
}

/* Info button */
.info-btn {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  border: 1px solid var(--border);
  background: none;
  color: var(--text-muted);
  font-size: 0.72rem;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: border-color var(--transition), color var(--transition);
  cursor: pointer;
}
.info-btn:hover { border-color: var(--accent); color: var(--accent); }

/* ── State list ──────────────────────────────────────────── */
.state-list {
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
}
.list-empty {
  font-size: 0.78rem;
  color: var(--text-faint);
  font-style: italic;
}

.state-row {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.5rem 0.6rem;
  border-radius: var(--radius);
  background: var(--bg-card);
  border: 1px solid transparent;
  cursor: pointer;
  transition: border-color var(--transition), background var(--transition);
}
.state-row:hover { border-color: var(--border); }
.state-row.highlighted {
  border-color: var(--border-hi);
  background: var(--bg-card2);
}

.state-dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  flex-shrink: 0;
}

.state-lbl {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  flex-shrink: 0;
  color: var(--text-muted);
  min-width: 18px;
}

.state-val {
  font-family: var(--font-mono);
  font-size: 0.69rem;
  font-weight: 300;
  color: var(--text);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  flex: 1;
  min-width: 0;
}

/* ── Gate palette ────────────────────────────────────────── */
.gate-panel { flex: 1; }
.gate-palette {
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
}
.gate-group { display: flex; flex-direction: column; gap: 0.45rem; }
.gate-group__lbl {
  font-size: 0.6rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-faint);
}
.gate-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

/* Gate chip */
.gate-chip {
  min-width: 40px;
  height: 32px;
  padding: 0 0.6rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 500;
  border-radius: var(--radius);
  border: 1px solid;
  cursor: grab;
  user-select: none;
  transition: opacity var(--transition), transform var(--transition), box-shadow var(--transition);
  letter-spacing: 0.03em;
}
.gate-chip:active { cursor: grabbing; transform: scale(0.95); }
.gate-chip.dragging { opacity: 0.4; }
.gate-chip:disabled, .gate-chip[data-disabled="true"] {
  cursor: not-allowed;
  opacity: 0.3;
  pointer-events: none;
}

/* Single-qubit: sage green tint */
.gate-chip.single {
  background: rgba(122,158,126,0.1);
  border-color: rgba(122,158,126,0.3);
  color: var(--accent-hi);
}
.gate-chip.single:hover {
  background: rgba(122,158,126,0.2);
  border-color: var(--accent);
  box-shadow: 0 2px 10px rgba(122,158,126,0.18);
}

/* Two-qubit: blue tint */
.gate-chip.two {
  background: rgba(77,141,230,0.1);
  border-color: rgba(77,141,230,0.3);
  color: #7ab0f0;
}
.gate-chip.two:hover {
  background: rgba(77,141,230,0.2);
  border-color: #4d8de6;
  box-shadow: 0 2px 10px rgba(77,141,230,0.18);
}

/* ── Circuit panel ───────────────────────────────────────── */
.circuit-panel {
  flex-shrink: 0;
  height: var(--circuit-h);
  background: var(--bg-panel);
  border-top: 1px solid var(--border);
  display: flex;
  flex-direction: column;
}

.circuit-hdr {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.55rem 1.2rem 0.4rem;
  flex-shrink: 0;
  border-bottom: 1px solid rgba(122,158,126,0.1);
}
.circuit-hdr__right {
  display: flex;
  align-items: center;
  gap: 1rem;
}
.circuit-hint {
  font-size: 0.62rem;
  color: var(--text-faint);
  letter-spacing: 0.04em;
}

.btn-clear {
  font-size: 0.68rem;
  font-weight: 400;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  background: none;
  border: 1px solid var(--border);
  padding: 0.2rem 0.65rem;
  border-radius: 3px;
  transition: color var(--transition), border-color var(--transition);
}
.btn-clear:hover { color: var(--red); border-color: rgba(230,88,77,0.4); }

.circuit-scroll-wrap {
  position: relative;
  flex: 1;
  min-height: 0;
  overflow: hidden;
}
.circuit-scroll {
  width: 100%;
  height: 100%;
  overflow-x: auto;
  overflow-y: hidden;
  scrollbar-width: thin;
  scrollbar-color: var(--border) transparent;
}
.circuit-scroll::-webkit-scrollbar { height: 4px; }
.circuit-scroll::-webkit-scrollbar-track { background: transparent; }
.circuit-scroll::-webkit-scrollbar-thumb { background: var(--border); border-radius: 2px; }

#circuitCanvas { display: block; height: 100%; }

.circuit-empty {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.78rem;
  color: var(--text-faint);
  font-style: italic;
  pointer-events: none;
  transition: opacity 0.3s ease;
}
.circuit-empty.hidden { opacity: 0; }

/* Right edge fade */
.circuit-fade {
  position: absolute;
  top: 0; right: 0; bottom: 0;
  width: 40px;
  background: linear-gradient(to right, transparent, var(--bg-panel));
  pointer-events: none;
}

/* ── Popup / Backdrop ─────────────────────────────────────── */
.popup-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.55);
  backdrop-filter: blur(3px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 200;
  opacity: 1;
  transition: opacity 0.2s ease;
}
.popup-backdrop.hidden { display: none; }

.popup {
  background: var(--bg-panel);
  border: 1px solid var(--border-hi);
  border-radius: 8px;
  padding: 1.5rem;
  width: 320px;
  max-width: 90vw;
  box-shadow: 0 24px 60px rgba(0,0,0,0.5);
  animation: popupIn 0.18s ease both;
}

@keyframes popupIn {
  from { opacity: 0; transform: scale(0.94) translateY(-8px); }
  to   { opacity: 1; transform: scale(1) translateY(0); }
}

.popup__title {
  font-family: var(--font-serif);
  font-size: 1.15rem;
  font-weight: 500;
  color: var(--text);
  margin-bottom: 0.3rem;
}
.popup__sub {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-bottom: 1rem;
  font-weight: 300;
  line-height: 1.5;
}

.popup__presets {
  display: flex;
  gap: 0.4rem;
  flex-wrap: wrap;
  margin: 1rem 0 0.75rem;
}
.preset {
  flex: 1;
  min-width: 48px;
  height: 32px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  transition: border-color var(--transition), background var(--transition);
}
.preset:hover { border-color: var(--accent); background: var(--accent-dim); color: var(--accent-hi); }
.preset.selected { border-color: var(--accent); background: var(--accent-dim); color: var(--accent-hi); }

.popup__custom {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 1.2rem;
}
.popup__custom input {
  flex: 1;
  padding: 0.5rem 0.75rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  outline: none;
  transition: border-color var(--transition);
}
.popup__custom input:focus { border-color: var(--accent); }
.popup__unit {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text-muted);
}

.popup__actions {
  display: flex;
  gap: 0.5rem;
  justify-content: flex-end;
}

.btn-cancel, .btn-confirm {
  padding: 0.44rem 1rem;
  border-radius: var(--radius);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  transition: background var(--transition), border-color var(--transition);
}
.btn-cancel {
  background: none;
  border: 1px solid var(--border);
  color: var(--text-muted);
}
.btn-cancel:hover { border-color: var(--text-muted); color: var(--text); }
.btn-confirm {
  background: var(--accent);
  border: 1px solid var(--accent);
  color: var(--bg);
}
.btn-confirm:hover { background: var(--accent-hi); border-color: var(--accent-hi); }

/* Control qubit list */
.control-list {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
  margin: 1rem 0 1.2rem;
}
.ctrl-opt {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.5rem 0.75rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  cursor: pointer;
  transition: border-color var(--transition), background var(--transition);
  text-align: left;
  color: var(--text);
}
.ctrl-opt:hover { border-color: var(--accent); background: var(--accent-dim); }
.ctrl-dot {
  width: 10px; height: 10px;
  border-radius: 50%;
  flex-shrink: 0;
}
.ctrl-name {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 500;
}
.ctrl-state {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: var(--text-muted);
  margin-left: auto;
}

/* ── Drop highlight on circuit ────────────────────────────── */
.circuit-scroll.drag-over {
  outline: 1px solid var(--accent);
  outline-offset: -1px;
}

/* ── Utility ─────────────────────────────────────────────── */
.hidden { display: none !important; }

/* ── Responsive ──────────────────────────────────────────── */
@media (max-width: 900px) {
  .workspace { flex-direction: column; }
  .sidebar {
    width: 100%;
    flex-direction: row;
    height: 200px;
    border-left: none;
    border-top: 1px solid var(--border);
    overflow-x: auto;
    overflow-y: hidden;
  }
  .state-panel, .gate-panel {
    min-width: 240px;
    border-bottom: none;
    border-right: 1px solid var(--border);
  }
  .circuit-panel {
    height: 160px;
  }
  :root { --circuit-h: 160px; }
}

@media (max-width: 600px) {
  :root { --sidebar-w: 100%; }
  .navbar__sub { display: none; }
  .qubit-count { display: none; }
}