/* ═══════════════════════════════════════════════════════════════
   VIANA ASSETS — Layout System  v3.0
   App Shell · Sidebar · Topbar · Content · Responsive Grid
═══════════════════════════════════════════════════════════════ */

/* ── App Shell ───────────────────────────────────────────── */
#app-shell {
  display: flex;
  min-height: 100dvh;
  background: var(--color-bg-base);
}

/* ── Sidebar ─────────────────────────────────────────────── */
.sidebar {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  width: var(--sidebar-width);
  background: var(--color-bg-primary);
  border-right: 1px solid var(--color-border);
  display: flex;
  flex-direction: column;
  z-index: var(--z-sticky);
  transition: width var(--duration-slow) var(--ease-default),
              transform var(--duration-slow) var(--ease-default);
  overflow: hidden;
}

.sidebar-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-5) var(--space-5) var(--space-4);
  border-bottom: 1px solid var(--color-border);
  min-height: var(--topbar-height);
  flex-shrink: 0;
}

.sidebar-logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
}
.sidebar-logo-img {
  width: 32px;
  height: 32px;
  object-fit: contain;
  flex-shrink: 0;
}
.sidebar-logo-text {
  font-size: var(--text-md);
  font-weight: var(--weight-bold);
  color: var(--color-text-primary);
  letter-spacing: var(--tracking-tight);
  white-space: nowrap;
}
.sidebar-logo-sub {
  font-size: var(--text-xs);
  color: var(--color-gold);
  font-weight: var(--weight-medium);
  letter-spacing: var(--tracking-wider);
  text-transform: uppercase;
}

.sidebar-nav {
  flex: 1;
  overflow-y: auto;
  overflow-x: hidden;
  padding: var(--space-4) var(--space-3);
}

.sidebar-section {
  margin-bottom: var(--space-6);
}
.sidebar-section-label {
  font-size: var(--text-xs);
  font-weight: var(--weight-semibold);
  color: var(--color-text-muted);
  letter-spacing: var(--tracking-widest);
  text-transform: uppercase;
  padding: 0 var(--space-3);
  margin-bottom: var(--space-2);
}

.nav-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-2-5) var(--space-3);
  border-radius: var(--radius-lg);
  color: var(--color-text-secondary);
  font-size: var(--text-sm);
  font-weight: var(--weight-medium);
  cursor: pointer;
  transition: all var(--duration-fast) var(--ease-default);
  white-space: nowrap;
  border: 1px solid transparent;
  text-decoration: none;
  user-select: none;
  position: relative;
}
.nav-item:hover {
  background: var(--color-bg-elevated);
  color: var(--color-text-primary);
  border-color: var(--color-border);
}
.nav-item.active {
  background: var(--color-accent-muted);
  color: var(--color-accent);
  border-color: rgba(124,92,252,0.2);
}
.nav-item .nav-icon {
  width: 20px;
  height: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-size: 18px;
  opacity: 0.8;
}
.nav-item.active .nav-icon { opacity: 1; }
.nav-item .nav-label { overflow: hidden; text-overflow: ellipsis; }

/* Sidebar collapse button */
.sidebar-collapse-btn {
  padding: var(--space-4) var(--space-5);
  border-top: 1px solid var(--color-border);
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: flex-end;
}

/* ── Sidebar User ────────────────────────────────────────── */
.sidebar-user {
  padding: var(--space-3) var(--space-4);
  border-top: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  gap: var(--space-3);
  cursor: pointer;
  transition: background var(--duration-fast) var(--ease-default);
  border-radius: var(--radius-md);
  margin: var(--space-2);
  flex-shrink: 0;
}
.sidebar-user:hover { background: var(--color-bg-elevated); }

.user-avatar {
  width: 34px;
  height: 34px;
  background: var(--color-accent-muted);
  border: 1px solid rgba(124,92,252,0.3);
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-sm);
  font-weight: var(--weight-bold);
  color: var(--color-accent);
  flex-shrink: 0;
}
.user-info { flex: 1; overflow: hidden; }
.user-name  {
  font-size: var(--text-sm);
  font-weight: var(--weight-semibold);
  color: var(--color-text-primary);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.user-plan {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
}

/* ── Topbar (mobile + page header) ──────────────────────── */
.topbar {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  background: var(--color-bg-primary);
  border-bottom: 1px solid var(--color-border);
  height: var(--topbar-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--content-padding-x);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  flex-shrink: 0;
}

.mobile-menu-btn {
  display: none;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-md);
  color: var(--color-text-secondary);
  transition: all var(--duration-fast);
}
.mobile-menu-btn:hover {
  background: var(--color-bg-elevated);
  color: var(--color-text-primary);
}

/* ── Main Content Area ───────────────────────────────────── */
.main-content {
  flex: 1;
  margin-left: var(--sidebar-width);
  display: flex;
  flex-direction: column;
  min-height: 100dvh;
  min-width: 0;
  transition: margin-left var(--duration-slow) var(--ease-default);
}

.page-content {
  flex: 1;
  padding: var(--content-padding-y) var(--content-padding-x);
  max-width: var(--content-max-width);
  width: 100%;
  margin: 0 auto;
}

/* ── Page Header ─────────────────────────────────────────── */
.page-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: var(--space-8);
  gap: var(--space-4);
  flex-wrap: wrap;
}
.page-title {
  font-size: var(--text-3xl);
  font-weight: var(--weight-bold);
  letter-spacing: var(--tracking-tight);
  color: var(--color-text-primary);
  line-height: var(--leading-tight);
}
.page-subtitle {
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
  margin-top: var(--space-1);
}
.page-actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex-shrink: 0;
}

/* ── KPI Grid ────────────────────────────────────────────── */
.kpi-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--space-4);
  margin-bottom: var(--space-6);
}

/* ── Content Grid (2-column) ─────────────────────────────── */
.content-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-6);
}
.content-grid.thirds {
  grid-template-columns: 1fr 1fr 1fr;
}
.content-grid.wide-left {
  grid-template-columns: 2fr 1fr;
}
.content-grid.wide-right {
  grid-template-columns: 1fr 2fr;
}

/* ── Section ─────────────────────────────────────────────── */
.section {
  margin-bottom: var(--space-8);
}
.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-4);
  gap: var(--space-3);
}
.section-title {
  font-size: var(--text-lg);
  font-weight: var(--weight-semibold);
  color: var(--color-text-primary);
}
.section-subtitle {
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
}

/* ── Sidebar Mobile Overlay ──────────────────────────────── */
.sidebar-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: var(--color-bg-overlay);
  backdrop-filter: blur(4px);
  z-index: calc(var(--z-sticky) - 1);
}

/* ── Auth Layout ─────────────────────────────────────────── */
.auth-layout {
  min-height: 100dvh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-bg-base);
  padding: var(--space-6);
  position: relative;
  overflow: hidden;
}

/* Radial gradient background for auth */
.auth-layout::before {
  content: '';
  position: absolute;
  top: -30%;
  left: 50%;
  transform: translateX(-50%);
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(124,92,252,0.08) 0%, transparent 70%);
  pointer-events: none;
}

.auth-card {
  width: 100%;
  max-width: 420px;
  background: var(--color-bg-card);
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-2xl);
  padding: var(--space-10) var(--space-8);
  box-shadow: var(--shadow-2xl);
  position: relative;
}

.auth-logo {
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: var(--space-8);
  flex-direction: column;
  gap: var(--space-3);
}
.auth-logo-img { width: 56px; height: 56px; }
.auth-logo-name {
  font-size: var(--text-2xl);
  font-weight: var(--weight-bold);
  letter-spacing: var(--tracking-tight);
  color: var(--color-text-primary);
}
.auth-logo-sub {
  font-size: var(--text-sm);
  color: var(--color-gold);
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
}

/* ── Responsive ──────────────────────────────────────────── */
@media (max-width: 1200px) {
  :root { --sidebar-width: 220px; }
}

@media (max-width: 1024px) {
  .content-grid { grid-template-columns: 1fr; }
  .content-grid.thirds { grid-template-columns: 1fr 1fr; }
  .content-grid.wide-left,
  .content-grid.wide-right { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  .sidebar {
    transform: translateX(-100%);
    width: var(--sidebar-width) !important;
    z-index: var(--z-modal);
  }
  .sidebar.open { transform: translateX(0); }
  .sidebar-overlay { display: block; }
  .sidebar-overlay.visible { display: block; }
  .main-content { margin-left: 0; }
  .mobile-menu-btn { display: flex; }
  .topbar { display: flex; }
  .content-grid.thirds { grid-template-columns: 1fr; }
  .kpi-grid { grid-template-columns: repeat(2, 1fr); }
  .page-header { flex-direction: column; align-items: flex-start; }
  .page-actions { width: 100%; justify-content: flex-start; }
  .page-title { font-size: var(--text-2xl); }
  #toast-container { right: var(--space-4); bottom: var(--space-4); left: var(--space-4); }
  .toast { max-width: 100%; }
  .auth-card { padding: var(--space-8) var(--space-6); }
}

@media (max-width: 480px) {
  :root {
    --content-padding-x: var(--space-4);
    --content-padding-y: var(--space-4);
  }
  .kpi-grid { grid-template-columns: 1fr 1fr; }
}