/* Breakpoints (mirror src/L0-token/breakpoint):
   sm 480px · md 768px · lg 1024px · xl 1280px · 2xl 1536px */
:root {
  color-scheme: light dark;
  --font-sans: "Open Sans", ui-sans-serif, system-ui, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-display: "SWDropclothDisplay", "SWDropcloth", "Open Sans", ui-sans-serif, system-ui, sans-serif;
  --font-mono: "Lucida Sans Typewriter", "Lucida Console", monaco, "Bitstream Vera Sans Mono", monospace;
  font-family: var(--font-sans);
  line-height: 1.5;
  font-size: var(--text-base);
  letter-spacing: -0.005em;
}
* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  background: var(--color-bg);
  color: var(--color-fg);
  overflow: hidden;
}

.shell {
  position: fixed;
  inset: 0;
  display: grid;
  grid-template-columns: 240px 1fr;
  background: var(--color-bg);
}

.rail {
  display: flex;
  flex-direction: column;
  gap: var(--space-4, 16px);
  padding: var(--space-4, 16px) var(--space-3, 12px);
  background: var(--color-surface);
  border-right: 1px solid var(--color-border);
  overflow: hidden auto;
}

.rail-logo {
  display: flex; align-items: center;
  padding: var(--space-2, 8px);
}
.rail-logo .wordmark {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: var(--text-lg);
  letter-spacing: -0.02em;
  color: var(--color-fg);
}

.rail-user label {
  display: block;
  font-size: var(--text-xs);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--color-fg-muted);
  margin: 0 var(--space-2) var(--space-1);
}
.rail-user select {
  width: 100%;
  padding: var(--space-2, 8px) var(--space-3, 12px);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm, 4px);
  background: var(--color-surface);
  color: var(--color-fg);
  font: inherit;
  cursor: pointer;
}
.rail-user select:focus-visible {
  outline: 2px solid var(--color-focus-ring);
  outline-offset: 2px;
}

.rail-bottom {
  margin-top: auto;
  display: flex;
  flex-direction: column;
  gap: var(--space-4, 16px);
}

.rail-welcome-style label {
  display: block;
  font-size: var(--text-xs);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--color-fg-muted);
  margin: 0 var(--space-2) var(--space-1);
}
.rail-welcome-style select {
  width: 100%;
  padding: var(--space-2, 8px) var(--space-3, 12px);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm, 4px);
  background: var(--color-surface);
  color: var(--color-fg);
  font: inherit;
  cursor: pointer;
}
.rail-welcome-style select:focus-visible {
  outline: 2px solid var(--color-focus-ring);
  outline-offset: 2px;
}
.rail-welcome-style[hidden] { display: none; }

.rail-theme label {
  display: block;
  font-size: var(--text-xs);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--color-fg-muted);
  margin: 0 var(--space-2) var(--space-1);
}
.rail-theme select {
  width: 100%;
  padding: var(--space-2, 8px) var(--space-3, 12px);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm, 4px);
  background: var(--color-surface);
  color: var(--color-fg);
  font: inherit;
  cursor: pointer;
}
.rail-theme select:focus-visible {
  outline: 2px solid var(--color-focus-ring);
  outline-offset: 2px;
}

.rail-nav {
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.rail-nav button.nav-item {
  display: flex;
  align-items: center;
  gap: var(--space-3, 12px);
  width: 100%;
  height: 44px;
  padding: 0 var(--space-3, 12px);
  border: 0;
  border-left: 3px solid transparent;
  border-radius: var(--radius-sm, 4px);
  background: transparent;
  color: var(--color-fg-muted);
  font: inherit;
  text-align: left;
  cursor: pointer;
  white-space: nowrap;
}
.rail-nav button.nav-item:hover {
  background: var(--color-surface-hover);
  color: var(--color-fg);
}
.rail-nav button.nav-item:focus-visible {
  outline: 2px solid var(--color-focus-ring);
  outline-offset: -2px;
}
.rail-nav button.nav-item[aria-current="page"] {
  background: var(--color-surface-hover);
  color: var(--color-primary);
  border-left-color: var(--color-primary);
}
.rail-nav .icon {
  flex: 0 0 22px;
  width: 22px; height: 22px;
  display: inline-flex; align-items: center; justify-content: center;
  color: currentColor;
}
.rail-nav .icon svg { width: 22px; height: 22px; display: block; }
.rail-nav .label { flex: 1 1 auto; font-size: var(--text-sm); }
.rail-nav .empty {
  padding: var(--space-3, 12px);
  font-size: var(--text-xs);
  color: var(--color-fg-muted);
}

.stage {
  position: relative;
  overflow: hidden;
  background: var(--color-bg);
}
.stage > canvas-stage {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
}
.page-host {
  position: absolute;
  inset: 0;
  display: block;
  z-index: 1;
}

/* xs/sm/md (anything below 768): hide the rail entirely; the canvas +
   page-host take the whole viewport. Navigation moves into
   <mobile-rail-fab> — a bottom-right floating button that opens a
   fullscreen <dialog showModal()>. The threshold matches the FAB's own
   [data-bp-down~="md"] gate so they're always in sync. */
:root[data-bp-down~="md"] .shell {
  grid-template-columns: 1fr;
  grid-template-rows: 1fr;
}
:root[data-bp-down~="md"] .rail {
  display: none;
}