*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  font-weight: var(--weight-normal);
  line-height: var(--leading-normal);
  letter-spacing: var(--tracking-normal);
  color: var(--color-text-primary);
  background: var(--color-bg-page);
}

h1, h2, h3, h4, h5, h6 {
  font-weight: var(--weight-semibold);
  letter-spacing: var(--tracking-tight);
  line-height: var(--leading-tight);
}

h1 { font-size: var(--text-3xl); }
h2 { font-size: var(--text-2xl); }
h3 { font-size: var(--text-xl); }
h4 { font-size: var(--text-lg); }

a {
  color: var(--color-text-primary);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

button, input, select, textarea {
  font-family: inherit;
  font-size: inherit;
  line-height: inherit;
  color: inherit;
}

img {
  max-width: 100%;
  display: block;
}

/* ─── Utilities ─── */

.hidden {
  display: none !important;
}

.text-mono {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  letter-spacing: 0;
}

.text-muted {
  color: var(--color-text-tertiary);
}

.text-secondary {
  color: var(--color-text-secondary);
}

.text-sm {
  font-size: var(--text-sm);
}

.text-xs {
  font-size: var(--text-xs);
}

.truncate {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

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

.flex-center {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.stack {
  display: flex;
  flex-direction: column;
}

.gap-1 { gap: var(--space-1); }
.gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }

/* ─── Skeleton Loading ─── */

.skeleton {
  background: linear-gradient(90deg, var(--color-bg-inset) 25%, var(--color-border-light) 50%, var(--color-bg-inset) 75%);
  background-size: 200% 100%;
  animation: skeleton-pulse 1.5s ease-in-out infinite;
  border-radius: var(--radius-sm);
}

@keyframes skeleton-pulse {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* ─── Toast Container ─── */

#toast-root {
  position: fixed;
  bottom: var(--space-6);
  right: var(--space-6);
  z-index: 10000;
  display: flex;
  flex-direction: column-reverse;
  gap: var(--space-2);
  pointer-events: none;
}

.toast {
  pointer-events: auto;
  padding: var(--space-3) var(--space-4);
  background: var(--color-bg-sidebar);
  color: var(--color-text-inverse);
  border-radius: var(--radius-lg);
  font-size: var(--text-sm);
  font-weight: var(--weight-medium);
  box-shadow: var(--shadow-lg);
  animation: toast-in 280ms cubic-bezier(0.16, 1, 0.3, 1);
  max-width: 360px;
}

.toast.toast-error {
  background: var(--color-danger);
}

.toast.toast-out {
  animation: toast-out 200ms ease forwards;
}

@keyframes toast-in {
  from {
    opacity: 0;
    transform: translateY(8px) scale(0.96);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

@keyframes toast-out {
  to {
    opacity: 0;
    transform: translateY(4px) scale(0.98);
  }
}

/* ─── View Transition ─── */

.view-enter {
  animation: view-enter 200ms ease;
}

@keyframes view-enter {
  from {
    opacity: 0;
    transform: translateY(4px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}