/* ============================================================================
   MAIN LAYOUT
   ============================================================================ */

body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

#app-root {
  width: 100%;
  max-width: none;
  min-height: 100vh;
  margin: 0;
  padding: var(--space-6);
  display: flex;
  flex-direction: column;
}

.page-shell {
  display: flex;
  flex-direction: column;
  flex: 1;
}

/* ============================================================================
   APP SHELL (Sidebar + Main)
   ============================================================================ */

.app-shell {
  display: grid;
  grid-template-columns: 260px minmax(0, 1fr);
  gap: var(--space-6);
  margin-top: 0;
  min-height: calc(100vh - var(--space-6) * 2);
  align-items: stretch;
  transition: grid-template-columns var(--transition-base);
  width: 100%;
  flex: 1;
}

.app-shell > aside,
.app-shell > main {
  min-height: 0;
}

.app-shell.sidebar-collapsed {
  grid-template-columns: 72px minmax(0, 1fr);
}

/* ============================================================================
   MAIN CONTENT AREA
   ============================================================================ */

main#app-main {
  background: var(--color-surface);
  border-radius: var(--radius-2xl);
  box-shadow: var(--shadow-lg);
  padding: var(--space-8) var(--space-8);
  border: 1px solid var(--color-border);
  display: flex;
  flex-direction: column;
  min-height: 0;
  position: relative;
}

/* Subtle gradient overlay */
main#app-main::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 200px;
  background: linear-gradient(180deg, rgba(45, 212, 191, 0.02) 0%, transparent 100%);
  border-radius: var(--radius-2xl) var(--radius-2xl) 0 0;
  pointer-events: none;
}

main#app-main > h1 {
  font-size: 1.75rem;
  font-weight: var(--font-weight-bold);
  color: var(--color-white);
  margin-bottom: var(--space-5);
  letter-spacing: -0.02em;
  position: relative;
}

#page-content {
  margin-top: 0;
  flex: 1;
  display: flex;
  flex-direction: column;
  min-height: 0;
  position: relative;
}

.page-section {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

/* Grid Utilities */
.grid {
  display: grid;
  gap: var(--space-3);
}

.grid-2 {
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.grid-3 {
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
}

.grid-4 {
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
}

/* ============================================================================
   SIDEBAR
   ============================================================================ */

.app-sidebar {
  width: 100%;
  padding: 0;
  box-sizing: border-box;
  display: flex;
  align-items: flex-start;
  position: sticky;
  top: var(--space-6);
  height: calc(100vh - var(--space-6) * 2);
  align-self: flex-start;
}

.sidebar-card {
  width: 100%;
  background: var(--color-surface);
  border-radius: var(--radius-2xl);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-lg);
  padding: var(--space-5);
  display: flex;
  flex-direction: column;
  gap: var(--space-5);
  flex: 1;
  min-height: 100%;
  justify-content: flex-start;
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

/* Subtle gradient at top */
.sidebar-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 120px;
  background: linear-gradient(180deg, rgba(45, 212, 191, 0.03) 0%, transparent 100%);
  pointer-events: none;
}

.sidebar-collapsed .sidebar-card {
  padding: var(--space-4) var(--space-2);
}

/* Sidebar Header */
.sidebar-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  margin-bottom: var(--space-1);
  position: relative;
}

.sidebar-header-left {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex: 1;
  min-width: 0;
}

.sidebar-logo {
  width: 38px;
  height: 38px;
  border-radius: var(--radius-md);
  flex-shrink: 0;
  box-shadow: var(--shadow-sm);
}

.sidebar-title {
  font-size: 1.25rem;
  font-weight: var(--font-weight-bold);
  color: var(--color-white);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: opacity var(--transition-fast), width var(--transition-fast);
  letter-spacing: -0.02em;
}

.sidebar-collapsed .sidebar-title {
  opacity: 0;
  width: 0;
}

/* Sidebar Toggle Button */
.sidebar-toggle-btn {
  width: 30px;
  height: 30px;
  border-radius: var(--radius-md);
  background: var(--glass-bg);
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition-fast);
  flex-shrink: 0;
}

.sidebar-toggle-btn:hover {
  background: var(--glass-bg-hover);
  border-color: var(--color-tertiary);
  color: var(--color-tertiary);
}

/* Sidebar Navigation */
.sidebar-nav {
  display: flex;
  flex-direction: column;
  gap: 4px;
  position: relative;
}

.nav-item,
.nav-utility {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-3);
  border-radius: var(--radius-lg);
  font-size: 0.9375rem;
  font-weight: var(--font-weight-medium);
  color: var(--color-text-muted);
  text-decoration: none;
  border: 1px solid transparent;
  background: transparent;
  cursor: pointer;
  transition: all var(--transition-fast);
  position: relative;
}

.nav-item:hover,
.nav-utility:hover {
  background: var(--glass-bg-hover);
  color: var(--color-white);
  transform: translateX(2px);
}

.nav-icon {
  width: 22px;
  height: 22px;
  display: inline-flex;
  justify-content: center;
  align-items: center;
  font-size: 1.125rem;
  flex-shrink: 0;
  transition: transform var(--transition-fast);
}

.nav-item:hover .nav-icon {
  transform: scale(1.1);
}

.nav-label {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: opacity var(--transition-fast), width var(--transition-fast);
}

.sidebar-collapsed .nav-label {
  opacity: 0;
  width: 0;
}

/* Active Nav Item */
.nav-item-active,
.nav-utility.nav-item-active {
  background: linear-gradient(135deg, var(--color-tertiary), var(--color-tertiary-dark));
  color: var(--color-black) !important;
  font-weight: var(--font-weight-semibold);
  border-color: transparent;
  box-shadow: 0 4px 16px rgba(45, 212, 191, 0.3);
}

.nav-item-active:hover,
.nav-utility.nav-item-active:hover {
  background: linear-gradient(135deg, var(--color-tertiary-light), var(--color-tertiary));
  transform: translateX(4px);
  color: var(--color-black) !important;
}

.nav-item-active .nav-icon,
.nav-utility.nav-item-active .nav-icon {
  opacity: 1;
}

/* Sidebar Footer */
.sidebar-footer {
  margin-top: auto;
  padding-top: var(--space-4);
  border-top: 1px solid var(--color-border);
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.nav-utility {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  padding: var(--space-2) var(--space-3);
}

/* ============================================================================
   RESPONSIVE DESIGN
   ============================================================================ */

@media (max-width: 1200px) {
  #app-root {
    padding: var(--space-5);
  }

  main#app-main {
    padding: var(--space-6);
  }

  .app-shell {
    gap: var(--space-5);
  }
}

@media (max-width: 900px) {
  .app-shell {
    grid-template-columns: 1fr;
  }

  .app-shell.sidebar-collapsed {
    grid-template-columns: 1fr;
  }

  .app-sidebar {
    width: 100%;
    position: relative;
    top: 0;
    height: auto;
  }

  .sidebar-card {
    min-height: auto;
    flex-direction: row;
    flex-wrap: wrap;
    gap: var(--space-3);
    padding: var(--space-4);
  }

  .sidebar-header {
    width: 100%;
  }

  .sidebar-nav {
    flex-direction: row;
    flex-wrap: wrap;
    width: 100%;
  }

  .sidebar-footer {
    width: 100%;
    flex-direction: row;
    border-top: none;
    padding-top: 0;
    margin-top: 0;
  }

  #app-root {
    padding: var(--space-4);
  }

  main#app-main {
    padding: var(--space-5);
  }

  main#app-main > h1 {
    font-size: 1.5rem;
  }
}

@media (max-width: 640px) {
  #app-root {
    padding: var(--space-3);
  }

  main#app-main {
    padding: var(--space-4);
    border-radius: var(--radius-xl);
  }

  main#app-main > h1 {
    font-size: 1.375rem;
    margin-bottom: var(--space-4);
  }

  .sidebar-card {
    padding: var(--space-3);
  }

  .nav-item,
  .nav-utility {
    padding: var(--space-2) var(--space-3);
    font-size: 0.875rem;
  }
}