/* ============================
   layout.css — Grid / Sidebar / Main
   Glassmorphism layout
   ============================ */

body {
  display: flex;
  min-height: 100vh;
  overflow-x: hidden;
  position: relative;
  z-index: 0;
}

/* ── SIDEBAR ── */
.sidebar {
  width: var(--sidebar-w);
  min-height: 100vh;
  background: var(--bg-sidebar);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  padding: 1.1rem 0.5rem 1rem;
  position: fixed;
  top: 0;
  left: 0;
  z-index: 200;
  overflow-y: auto;
  transition: transform 0.3s ease;
  box-shadow: 4px 0 24px rgba(0,0,0,0.18);
}

.sidebar-logo {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0.2rem 0.6rem 0.9rem;
  border-bottom: 1px solid var(--border);
  margin-bottom: 0.5rem;
}

.logo-mark {
  width: 32px;
  height: 32px;
  flex-shrink: 0;
  filter: drop-shadow(0 0 6px var(--accent-1));
  transition: filter 0.28s ease;
}

.sidebar-logo:hover .logo-mark {
  filter: drop-shadow(0 0 12px var(--accent-1));
}

.logo-text {
  font-size: 0.88rem;
  font-weight: 700;
  letter-spacing: 3px;
  color: var(--text-primary);
  text-transform: uppercase;
}

.sidebar-version {
  font-size: 0.55rem;
  color: var(--text-dim);
  padding: 0 0.6rem 0.8rem;
  letter-spacing: 1.5px;
  text-transform: uppercase;
}

.nav-section-label {
  font-size: 0.55rem;
  letter-spacing: 2.5px;
  color: var(--text-dim);
  padding: 0.75rem 0.7rem 0.28rem;
  text-transform: uppercase;
  font-weight: 600;
}

.nav-btn {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  width: 100%;
  padding: 0.44rem 0.65rem;
  background: none;
  border: none;
  border-left: 2.5px solid transparent;
  border-radius: 0 9px 9px 0;
  color: var(--text-secondary);
  font-family: var(--font-ui);
  font-size: 0.72rem;
  font-weight: 500;
  cursor: pointer;
  text-align: left;
  transition: all 0.18s ease;
}

.nav-btn:hover {
  background: var(--bg-btn);
  color: var(--text-primary);
  backdrop-filter: blur(10px);
}

.nav-btn.active {
  background: linear-gradient(90deg,
    rgba(187,134,252,0.16) 0%,
    rgba(187,134,252,0.05) 100%);
  color: var(--accent-1);
  border-left-color: var(--accent-1);
}

[data-theme="light"] .nav-btn.active {
  background: linear-gradient(90deg,
    rgba(108,92,231,0.12) 0%,
    rgba(108,92,231,0.03) 100%);
  border-left-color: var(--accent-1);
}

.nav-icon {
  font-size: 0.88rem;
  width: 18px;
  text-align: center;
  flex-shrink: 0;
}

.sidebar-footer {
  margin-top: auto;
  padding-top: 0.9rem;
  border-top: 1px solid var(--border);
}

.theme-toggle-btn {
  width: 100%;
  padding: 0.48rem 0.7rem;
  background: var(--bg-btn);
  border: 1px solid var(--border);
  border-radius: 9px;
  color: var(--text-secondary);
  font-family: var(--font-ui);
  font-size: 0.72rem;
  font-weight: 500;
  cursor: pointer;
  backdrop-filter: blur(10px);
  transition: all 0.2s;
}

.theme-toggle-btn:hover {
  border-color: var(--accent-1);
  color: var(--accent-1);
  box-shadow: var(--glow);
}

/* ── MAIN ── */
.main-content {
  margin-left: var(--sidebar-w);
  flex: 1;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  padding: 1.4rem;
  gap: 1.3rem;
  overflow-y: auto;
  position: relative;
  z-index: 1;
}

/* ── DISPLAY BAR ── */
.display-bar {
  background: var(--bg-display);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  border: 1px solid var(--border);
  border-radius: var(--radius-card);
  padding: 1.1rem 1.6rem;
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 0.15rem;
  box-shadow: var(--glow), var(--shadow-card);
  position: sticky;
  top: 0;
  z-index: 10;
  /* Top shimmer line */
  overflow: hidden;
}

.display-bar::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 1px;
  background: linear-gradient(90deg,
    transparent, var(--accent-1), transparent);
  opacity: 0.6;
}

.display-panel-name {
  font-size: 0.55rem;
  letter-spacing: 2.5px;
  color: var(--text-dim);
  text-transform: uppercase;
  align-self: flex-start;
  font-weight: 600;
}

.display-expression {
  font-family: var(--font-display);
  font-size: 0.85rem;
  color: var(--text-secondary);
  min-height: 1.2em;
  word-break: break-all;
  text-align: right;
}

.display-result {
  font-family: var(--font-display);
  font-size: 2.6rem;
  font-weight: 700;
  color: var(--text-primary);
  word-break: break-all;
  text-align: right;
  line-height: 1.1;
  letter-spacing: -1px;
}

.display-info {
  font-size: 0.68rem;
  color: var(--accent-1);
  min-height: 1em;
  font-family: var(--font-display);
}

/* ── PANELS ── */
.panel {
  display: none;
  animation: fadeSlide 0.22s ease;
}

.panel.active {
  display: block;
}

/* ── HAMBURGER ── */
.hamburger {
  display: none;
  position: fixed;
  top: 1rem;
  left: 1rem;
  z-index: 300;
  background: var(--bg-card);
  backdrop-filter: blur(16px);
  border: 1px solid var(--border);
  border-radius: 9px;
  padding: 0.5rem;
  cursor: pointer;
  flex-direction: column;
  gap: 4px;
}

.hamburger span {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: all 0.2s;
}

/* ── RESPONSIVE ── */
@media (max-width: 768px) {
  .sidebar {
    transform: translateX(-100%);
  }
  .sidebar.open {
    transform: translateX(0);
  }
  .main-content {
    margin-left: 0;
    padding: 1rem 0.75rem;
    padding-top: 4rem;
  }
  .hamburger {
    display: flex;
  }
  .display-result {
    font-size: 2rem;
  }
}