/* App Layout & Screen Containers */

.app-container {
  max-width: 480px;
  margin: 0 auto;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: radial-gradient(circle at top center, hsla(270, 50%, 15%, 0.4) 0%, var(--color-bg-primary) 70%);
  position: relative;
  padding-bottom: 84px; /* Space for BottomNav */
}

/* Header */
.app-header {
  position: sticky;
  top: 0;
  z-index: 50;
  padding: var(--space-4);
  background: hsla(230, 25%, 8%, 0.85);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border-bottom: var(--glass-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.header-title {
  font-family: var(--font-display);
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-primary);
}

/* Bottom Navigation */
.app-bottom-nav {
  position: fixed;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 100%;
  max-width: 480px;
  height: 72px;
  z-index: 50;
  background: hsla(230, 25%, 10%, 0.9);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border-top: var(--glass-border);
  display: flex;
  align-items: center;
  justify-content: space-around;
  padding: 0 var(--space-2);
}

.nav-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-1);
  color: var(--color-text-muted);
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-semibold);
  transition: color var(--transition-fast), transform var(--transition-fast);
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-md);
}

.nav-item.is-active {
  color: var(--color-accent-violet);
}

.nav-item.is-active .nav-icon {
  transform: translateY(-2px);
  color: var(--color-accent-violet);
}

.nav-icon {
  font-size: 1.35rem;
}

/* Screen Main Container */
.screen-content {
  flex: 1;
  padding: var(--space-4);
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}

/* Phase Cards in HomeScreen */
.phase-card {
  padding: var(--space-4);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.phase-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.phase-title {
  font-family: var(--font-display);
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-bold);
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

/* Modal Overlay */
.modal-overlay {
  position: fixed;
  inset: 0;
  z-index: 100;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(8px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-4);
}

.modal-content {
  width: 100%;
  max-width: 400px;
  background: var(--color-bg-elevated);
  border: var(--glass-border);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.5);
}