/* =========================================================
   SITISE INVOICE MANAGER - LAYOUT & NAVIGATION
   ========================================================= */

.app-wrapper {
  display: flex;
  min-height: 100vh;
  position: relative;
  background-color: var(--bg-app);
}

/* Sidebar Styles */
.app-sidebar {
  width: var(--sidebar-width);
  background-color: var(--bg-sidebar);
  border-right: 1px solid var(--border-card);
  display: flex;
  flex-direction: column;
  position: fixed;
  top: 0;
  bottom: 0;
  left: 0;
  z-index: 40;
  transition: transform var(--transition-normal);
}

.sidebar-header {
  padding: 1.5rem 1.25rem;
  display: flex;
  align-items: center;
  gap: 0.875rem;
  border-bottom: 1px solid var(--border-subtle);
}

.brand-logo-img {
  height: 38px;
  width: auto;
  object-fit: contain;
  filter: drop-shadow(0 2px 8px rgba(0, 163, 224, 0.3));
}

.brand-title {
  display: flex;
  flex-direction: column;
}

.brand-name {
  font-family: var(--font-family-display);
  font-weight: 700;
  font-size: 1.125rem;
  letter-spacing: -0.02em;
  color: var(--text-primary);
  line-height: 1.2;
}

.brand-subtitle {
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-primary-light);
}

/* Sidebar Navigation */
.sidebar-nav {
  flex: 1;
  padding: 1.25rem 0.75rem;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 0.375rem;
}

.nav-label {
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  padding: 0.75rem 0.75rem 0.25rem;
  font-weight: 600;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 0.875rem;
  color: var(--text-secondary);
  text-decoration: none;
  border-radius: var(--radius-sm);
  font-weight: 500;
  font-size: 0.9rem;
  transition: all var(--transition-fast);
  cursor: pointer;
  border: 1px solid transparent;
}

.nav-item:hover {
  background-color: var(--bg-card);
  color: var(--text-primary);
  border-color: var(--border-subtle);
  transform: translateX(2px);
}

.nav-item.active {
  background: linear-gradient(90deg, rgba(0, 163, 224, 0.15), rgba(0, 163, 224, 0.04));
  color: var(--color-primary-light);
  border-color: rgba(0, 163, 224, 0.25);
  font-weight: 600;
}

.nav-item.active .nav-icon {
  color: var(--color-primary);
}

.nav-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 20px;
  height: 20px;
  color: var(--text-muted);
  transition: color var(--transition-fast);
}

.nav-badge {
  margin-left: auto;
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.15rem 0.5rem;
  border-radius: var(--radius-full);
  background-color: var(--bg-card-subtle);
  color: var(--text-secondary);
}

/* Sidebar Footer */
.sidebar-footer {
  padding: 1rem 1.25rem;
  border-top: 1px solid var(--border-subtle);
  background-color: var(--bg-card-subtle);
}

.system-status-indicator {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.75rem;
  color: var(--text-muted);
}

.status-dot-container {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--status-paid);
  box-shadow: 0 0 8px rgba(16, 185, 129, 0.6);
  animation: pulse-dot 2s infinite;
}

@keyframes pulse-dot {
  0%, 100% { transform: scale(1); opacity: 1; }
  50% { transform: scale(1.2); opacity: 0.7; }
}

/* Main Content Area */
.app-main {
  flex: 1;
  margin-left: var(--sidebar-width);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  position: relative;
  background-color: var(--bg-app);
}

/* Header / Top Bar */
.app-header {
  height: var(--header-height);
  background-color: var(--bg-card);
  border-bottom: 1px solid var(--border-card);
  position: sticky;
  top: 0;
  z-index: 30;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 2rem;
  transition: background-color var(--transition-normal), border-color var(--transition-normal);
}

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

.menu-toggle-btn {
  display: none;
  background: transparent;
  border: 1px solid var(--border-card);
  color: var(--text-secondary);
  border-radius: var(--radius-sm);
  padding: 0.5rem;
  cursor: pointer;
}

.header-page-title {
  font-family: var(--font-family-display);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.875rem;
}

/* Content Container */
.content-container {
  flex: 1;
  padding: 2rem;
  max-width: 1440px;
  width: 100%;
  margin: 0 auto;
}

/* View Sections (SPA Views) */
.view-section {
  display: none;
  animation: fadeIn 0.25s ease-in-out;
}

.view-section.active {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Responsive Breakpoints */
@media (max-width: 1024px) {
  .app-sidebar {
    transform: translateX(-100%);
  }

  .app-sidebar.open {
    transform: translateX(0);
    box-shadow: var(--shadow-xl);
  }

  .app-main {
    margin-left: 0;
  }

  .menu-toggle-btn {
    display: flex;
    align-items: center;
    justify-content: center;
  }

  .content-container {
    padding: 1.25rem;
  }

  .app-header {
    padding: 0 1.25rem;
  }
}