:root {
  /* Dark (black) mode by default */
  color-scheme: dark;

  --ui-font-sans: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Helvetica,
    Arial, "Apple Color Emoji", "Segoe UI Emoji";
  --ui-font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono",
    "Courier New", monospace;

  --ui-bg: #0b0f14;
  --ui-surface: #0f1623;
  --ui-surface-2: #121c2c;
  --ui-text: #e6edf3;
  --ui-text-secondary: #9fb1c7;
  --ui-text-tertiary: #8aa0b8;
  --ui-border: #243247;

  --ui-accent: #2d8cff;
  --ui-accent-strong: #1d4ed8;
  --ui-accent-soft: rgba(45, 140, 255, 0.14);

  --ui-success: #16a34a;
  --ui-warning: #d97706;
  --ui-danger: #dc2626;

  --ui-radius-sm: 10px;
  --ui-radius: 14px;
  --ui-radius-lg: 18px;

  --ui-shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.35);
  --ui-shadow: 0 18px 50px rgba(0, 0, 0, 0.45);
  --ui-shadow-lg: 0 26px 80px rgba(0, 0, 0, 0.55);

  --ui-focus-ring: 0 0 0 3px rgba(45, 140, 255, 0.35);

  --ui-container: 1040px;

  --ui-space-1: 4px;
  --ui-space-2: 8px;
  --ui-space-3: 12px;
  --ui-space-4: 16px;
  --ui-space-5: 20px;
  --ui-space-6: 24px;
  --ui-space-8: 32px;
  --ui-space-10: 40px;
}

/* Optional: force light mode per page by setting <html data-ui-theme="light"> */
:root[data-ui-theme="light"] {
  color-scheme: light;
  --ui-bg: #f7f7f8;
  --ui-surface: #ffffff;
  --ui-surface-2: #f3f4f6;
  --ui-text: #111827;
  --ui-text-secondary: #4b5563;
  --ui-text-tertiary: #6b7280;
  --ui-border: rgba(17, 24, 39, 0.12);

  --ui-shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.06);
  --ui-shadow: 0 12px 30px rgba(0, 0, 0, 0.08);
  --ui-shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.12);
}

* {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
}

body {
  margin: 0;
  background: var(--ui-bg);
  color: var(--ui-text);
  font-family: var(--ui-font-sans);
  line-height: 1.5;
  text-rendering: optimizeLegibility;
}

img {
  max-width: 100%;
  height: auto;
}

a {
  color: inherit;
}

.ui-requires-admin {
  display: none !important;
}

:focus-visible {
  outline: none;
  box-shadow: var(--ui-focus-ring);
  border-radius: var(--ui-radius-sm);
}

@media (prefers-reduced-motion: reduce) {
  * {
    transition: none !important;
    animation: none !important;
    scroll-behavior: auto !important;
  }
}

.ui-container {
  width: min(var(--ui-container), 100%);
  margin: 0 auto;
  padding: var(--ui-space-8) var(--ui-space-4);
}

@media (max-width: 640px) {
  .ui-container {
    padding: var(--ui-space-6) var(--ui-space-3);
  }
}

.ui-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--ui-space-4);
}

.ui-title {
  margin: 0;
  font-size: 1.6rem;
  font-weight: 700;
  letter-spacing: -0.01em;
}

.ui-subtitle {
  margin: var(--ui-space-2) 0 0;
  color: var(--ui-text-secondary);
  max-width: 70ch;
}

.ui-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: var(--ui-space-4);
}

.ui-card {
  display: flex;
  flex-direction: column;
  padding: var(--ui-space-5);
  border-radius: var(--ui-radius);
  border: 1px solid var(--ui-border);
  background: var(--ui-surface);
  box-shadow: var(--ui-shadow-sm);
  text-decoration: none;
  transition: transform 120ms ease, box-shadow 120ms ease, border-color 120ms ease;
}

.ui-card__tag {
  margin-top: auto;
  align-self: flex-start;
}

.ui-card:hover {
  box-shadow: var(--ui-shadow);
  border-color: rgba(45, 140, 255, 0.35);
  transform: translateY(-2px);
  text-decoration: none;
}

.ui-card:active {
  transform: translateY(0);
}

.ui-card__title {
  margin: 0 0 var(--ui-space-2);
  font-size: 1.1rem;
  font-weight: 700;
}

.ui-card__desc {
  margin: 0 0 var(--ui-space-3);
  color: var(--ui-text-secondary);
}

.ui-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 4px 10px;
  border-radius: 999px;
  border: 1px solid var(--ui-border);
  background: var(--ui-surface-2);
  color: var(--ui-text-secondary);
  font-size: 0.85rem;
  font-weight: 600;
}

.ui-badge--accent {
  border-color: rgba(45, 140, 255, 0.35);
  background: var(--ui-accent-soft);
  color: var(--ui-text);
}

.ui-btn {
  appearance: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--ui-border);
  background: var(--ui-surface);
  color: var(--ui-text);
  padding: 10px 14px;
  border-radius: var(--ui-radius-sm);
  cursor: pointer;
  font-weight: 650;
  box-shadow: var(--ui-shadow-sm);
  text-decoration: none;
  transition: transform 120ms ease, box-shadow 120ms ease, background 120ms ease,
    border-color 120ms ease;
}

.ui-btn:hover {
  box-shadow: var(--ui-shadow);
  border-color: rgba(45, 140, 255, 0.25);
}

.ui-btn:active {
  transform: translateY(1px);
}

.ui-btn--primary {
  background: var(--ui-accent-soft);
  border-color: rgba(45, 140, 255, 0.45);
}

.ui-btn--primary:hover {
  background: rgba(45, 140, 255, 0.2);
}

.ui-btn--danger {
  background: rgba(220, 38, 38, 0.12);
  border-color: rgba(220, 38, 38, 0.45);
}

.ui-btn--danger:hover {
  border-color: rgba(220, 38, 38, 0.65);
}

.ui-btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  box-shadow: none;
}

/* Page-level back button (top-left) */
body.ui-has-back {
  padding-top: calc(env(safe-area-inset-top, 0px) + var(--ui-space-4) + 44px);
}

body.ui-has-auth {
  padding-top: calc(env(safe-area-inset-top, 0px) + var(--ui-space-4) + 44px);
}

.ui-auth {
  position: fixed;
  top: calc(env(safe-area-inset-top, 0px) + var(--ui-space-4));
  right: calc(env(safe-area-inset-right, 0px) + var(--ui-space-4));
  z-index: 1000;
  display: flex;
  align-items: center;
  gap: var(--ui-space-2);
  flex-wrap: wrap;
}

.ui-auth.ui-auth--slot {
  position: static;
  inset: auto;
  z-index: auto;
  display: grid;
  align-items: start;
  justify-items: stretch;
}

.ui-auth.ui-auth--slot .ui-btn {
  width: 100%;
  justify-content: center;
}

.ui-auth-block {
  position: fixed;
  inset: 0;
  z-index: 2000;
  background: rgba(0, 0, 0, 0.55);
  display: grid;
  place-items: center;
  padding: var(--ui-space-4);
}

.ui-auth-block__card {
  width: min(560px, 100%);
  border-radius: var(--ui-radius-lg);
  border: 1px solid var(--ui-border);
  background: var(--ui-surface);
  box-shadow: var(--ui-shadow-lg);
  padding: var(--ui-space-5);
  display: grid;
  gap: var(--ui-space-2);
}

.ui-auth-block__title {
  font-weight: 800;
  letter-spacing: -0.01em;
}

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

.ui-back {
  position: fixed;
  top: calc(env(safe-area-inset-top, 0px) + var(--ui-space-4));
  left: calc(env(safe-area-inset-left, 0px) + var(--ui-space-4));
  z-index: 1000;
  padding: 8px 12px;
}

.ui-field {
  display: grid;
  gap: 6px;
}

.ui-label {
  font-size: 0.9rem;
  font-weight: 650;
}

.ui-help {
  color: var(--ui-text-secondary);
  font-size: 0.85rem;
}

.ui-input,
.ui-select,
.ui-textarea {
  width: 100%;
  padding: 10px 12px;
  border-radius: var(--ui-radius-sm);
  border: 1px solid var(--ui-border);
  background: var(--ui-surface);
  color: var(--ui-text);
  font-size: 1rem;
}

.ui-textarea {
  min-height: 120px;
  resize: vertical;
  font-family: var(--ui-font-sans);
}

.ui-pre,
pre.ui-pre {
  border-radius: var(--ui-radius);
  border: 1px solid var(--ui-border);
  background: var(--ui-surface-2);
  padding: var(--ui-space-4);
  overflow: auto;
  font-family: var(--ui-font-mono);
  font-size: 0.95rem;
  line-height: 1.5;
}

.ui-kbd {
  font-family: var(--ui-font-mono);
  border: 1px solid var(--ui-border);
  background: var(--ui-surface-2);
  padding: 2px 6px;
  border-radius: 8px;
  font-size: 0.9em;
}

/* App shell (sidebar layout) */
.ui-shell {
  min-height: 100vh;
  display: grid;
  grid-template-columns: 280px 1fr;
}

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

.ui-sidebar {
  position: sticky;
  top: 0;
  height: 100vh;
  overflow: hidden;
  border-right: 1px solid var(--ui-border);
  background: var(--ui-surface);
}

@media (max-width: 900px) {
  .ui-sidebar {
    position: relative;
    height: auto;
    border-right: none;
    border-bottom: 1px solid var(--ui-border);
  }
}

.ui-sidebar__scroll {
  height: 100%;
  overflow: auto;
  padding: var(--ui-space-6) var(--ui-space-3);
  display: grid;
  gap: var(--ui-space-6);
}

@media (max-width: 900px) {
  .ui-sidebar__scroll {
    padding: var(--ui-space-4) var(--ui-space-3);
  }
}

.ui-sidebar__brand {
  display: flex;
  align-items: center;
  gap: var(--ui-space-2);
  text-decoration: none;
  padding: var(--ui-space-2) var(--ui-space-2);
  border-radius: var(--ui-radius-sm);
}

.ui-sidebar__brand:hover {
  background: var(--ui-surface-2);
}

.ui-sidebar__brandText {
  display: grid;
  line-height: 1.15;
}

.ui-sidebar__brandTitle {
  font-weight: 850;
  letter-spacing: -0.02em;
}

.ui-sidebar__brandSub {
  color: var(--ui-text-secondary);
  font-size: 0.85rem;
}

.ui-nav {
  display: grid;
  gap: var(--ui-space-4);
}

.ui-nav__section {
  display: grid;
  gap: var(--ui-space-2);
}

.ui-nav__heading {
  margin: 0;
  padding: 0 var(--ui-space-2);
  color: var(--ui-text-tertiary);
  font-size: 0.75rem;
  font-weight: 750;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.ui-nav__list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 2px;
}

.ui-nav__link {
  display: flex;
  align-items: center;
  gap: var(--ui-space-2);
  padding: 10px 12px;
  border-radius: var(--ui-radius-sm);
  border: 1px solid transparent;
  text-decoration: none;
  color: var(--ui-text-secondary);
  transition: background 120ms ease, border-color 120ms ease, color 120ms ease;
}

.ui-nav__link:hover {
  background: var(--ui-surface-2);
  color: var(--ui-text);
}

.ui-nav__link[aria-current="page"] {
  background: var(--ui-accent-soft);
  border-color: rgba(45, 140, 255, 0.35);
  color: var(--ui-text);
}

.ui-nav__icon {
  width: 18px;
  height: 18px;
  flex: 0 0 auto;
  color: var(--ui-text-tertiary);
}

.ui-nav__link[aria-current="page"] .ui-nav__icon {
  color: var(--ui-text);
}

.ui-nav__item--sub .ui-nav__link {
  padding-left: 38px;
}

.ui-sidebar__footer {
  display: grid;
  gap: var(--ui-space-2);
  padding: var(--ui-space-3);
  border-radius: var(--ui-radius);
  border: 1px solid var(--ui-border);
  background: var(--ui-surface-2);
}

.ui-main {
  min-width: 0;
  padding: var(--ui-space-8) var(--ui-space-6);
}

@media (max-width: 900px) {
  .ui-main {
    padding: var(--ui-space-6) var(--ui-space-3);
  }
}

.ui-main__content {
  width: min(var(--ui-container), 100%);
  margin: 0 auto;
}
