/* reliefkit — design tokens first, then components. Every spacing value comes
   from the 4px scale; every colour from the ramp below. */

:root {
  --s1: 4px;  --s2: 8px;  --s3: 12px; --s4: 16px;
  --s5: 24px; --s6: 32px; --s7: 48px;

  --fs-xs: 12px; --fs-sm: 13px; --fs-md: 14px;
  --fs-lg: 16px; --fs-xl: 20px;

  --radius: 6px;
  --radius-lg: 10px;
  --sidebar: 336px;

  --bg:        #f7f7f5;
  --surface:   #ffffff;
  --surface-2: #f0f0ed;
  --border:    #dedcd7;
  --border-strong: #c4c1ba;
  --text:      #1b1b19;
  --muted:     #67655f;
  --primary:   #0f6f66;
  --primary-hover: #0b574f;
  --on-primary: #ffffff;
  --danger:    #a3341f;
  --danger-bg: #fdf0ec;
  --warn:      #7a5300;
  --focus:     #0f6f66;
  --shadow: 0 1px 2px rgba(0,0,0,.05), 0 4px 12px rgba(0,0,0,.05);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg:        #131417;
    --surface:   #1c1e22;
    --surface-2: #24262b;
    --border:    #33363d;
    --border-strong: #474b54;
    --text:      #e8eaec;
    --muted:     #9ca1a9;
    --primary:   #35b3a4;
    --primary-hover: #47c7b7;
    --on-primary: #07231f;
    --danger:    #f08a70;
    --danger-bg: #2c1a16;
    --warn:      #d8a94a;
    --focus:     #35b3a4;
    --shadow: 0 1px 2px rgba(0,0,0,.4), 0 4px 14px rgba(0,0,0,.3);
  }
}

* { box-sizing: border-box; }

/* Components below set display: flex/grid, which outranks the [hidden]
   attribute's UA default. Without this, anything toggled via .hidden stays
   on screen. */
[hidden] { display: none !important; }

body {
  margin: 0;
  font: var(--fs-md)/1.55 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3 { margin: 0; line-height: 1.2; }

kbd {
  font: 500 var(--fs-xs)/1 ui-monospace, SFMono-Regular, Menlo, monospace;
  padding: 3px 5px;
  border: 1px solid var(--border-strong);
  border-bottom-width: 2px;
  border-radius: 4px;
  background: var(--surface-2);
  white-space: nowrap;
}

:focus-visible {
  outline: 2px solid var(--focus);
  outline-offset: 2px;
  border-radius: 3px;
}

.skip-link {
  position: absolute; left: var(--s3); top: -48px;
  padding: var(--s2) var(--s3); z-index: 100;
  background: var(--primary); color: var(--on-primary);
  border-radius: var(--radius); text-decoration: none;
  transition: top .15s ease-out;
}
.skip-link:focus { top: var(--s3); }

/* ── topbar ─────────────────────────────────────────────────── */

.topbar {
  display: flex; align-items: baseline; gap: var(--s3);
  padding: var(--s3) var(--s4);
  border-bottom: 1px solid var(--border);
  background: var(--surface);
}
.topbar h1 {
  font-size: var(--fs-xl); font-weight: 600; letter-spacing: -.02em;
}
.topbar h1 span { color: var(--primary); }
.tagline { margin: 0; color: var(--muted); font-size: var(--fs-sm); }

.status {
  margin-left: auto; font-size: var(--fs-sm); color: var(--muted);
  font-variant-numeric: tabular-nums;
}

/* ── layout ─────────────────────────────────────────────────── */

.layout {
  display: grid;
  grid-template-columns: var(--sidebar) minmax(0, 1fr);
  height: calc(100vh - 53px);
}

.sidebar {
  overflow-y: auto;
  border-right: 1px solid var(--border);
  background: var(--surface);
}

.panel {
  padding: var(--s4);
  border-bottom: 1px solid var(--border);
}
.panel:last-child { border-bottom: none; padding-bottom: 0; }

/* The export button is the primary action; keep it reachable without
   scrolling the sidebar to the end. */
.sticky-action {
  position: sticky; bottom: 0;
  margin: var(--s4) calc(-1 * var(--s4)) 0;
  padding: var(--s3) var(--s4);
  background: var(--surface);
  border-top: 1px solid var(--border);
}
.sticky-action .hint { margin-top: var(--s2); }
.panel h2 {
  font-size: var(--fs-xs); font-weight: 600;
  text-transform: uppercase; letter-spacing: .07em;
  color: var(--muted);
  margin-bottom: var(--s3);
}

/* ── fields ─────────────────────────────────────────────────── */

.field { margin-bottom: var(--s4); }
.field:last-child { margin-bottom: 0; }

.field label, .field-label {
  display: flex; align-items: center; gap: var(--s2);
  font-size: var(--fs-sm); font-weight: 500;
  margin-bottom: var(--s2);
}

/* Resolution note under the mesh-detail slider: neutral when the mesh matches
   the tool, amber when it is finer than the tool can reproduce. */
.hint.over { color: var(--warn); font-weight: 500; }

.hint {
  margin: var(--s2) 0 0;
  font-size: var(--fs-xs); color: var(--muted);
  max-width: 60ch;
}

.tag {
  margin-left: auto;
  font: 500 var(--fs-xs)/1 ui-monospace, SFMono-Regular, Menlo, monospace;
  padding: 3px var(--s2);
  border-radius: 4px;
  background: var(--surface-2);
  color: var(--text);
}

input[type="number"], select {
  width: 100%;
  padding: var(--s2) var(--s3);
  min-height: 38px;
  font: inherit; font-size: var(--fs-md);
  color: var(--text);
  background: var(--surface);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius);
}
input[type="number"]:hover, select:hover { border-color: var(--muted); }

.input-unit { display: flex; align-items: stretch; }
.input-unit input { border-radius: var(--radius) 0 0 var(--radius); }
.unit {
  display: flex; align-items: center;
  padding: 0 var(--s3);
  font-size: var(--fs-sm); color: var(--muted);
  background: var(--surface-2);
  border: 1px solid var(--border-strong); border-left: none;
  border-radius: 0 var(--radius) var(--radius) 0;
}
.unit-lead {
  border-left: 1px solid var(--border-strong); border-right: none;
  border-radius: var(--radius) 0 0 var(--radius);
}
.input-unit .unit-lead + input { border-radius: 0 var(--radius) var(--radius) 0; }

input[type="range"] {
  width: 100%; height: 24px; margin: 0;
  accent-color: var(--primary);
}

.check {
  display: flex; align-items: flex-start; gap: var(--s2);
  font-size: var(--fs-sm); cursor: pointer;
  margin-bottom: var(--s3);
  min-height: 24px;
}
.check input { margin: 3px 0 0; accent-color: var(--primary); flex-shrink: 0; }

/* ── segmented control ──────────────────────────────────────── */

.segmented {
  display: flex; gap: 2px; padding: 2px;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: var(--s4);
}
.segmented button {
  flex: 1; padding: var(--s2) var(--s3); min-height: 34px;
  font: inherit; font-size: var(--fs-sm); font-weight: 500;
  color: var(--muted); background: none;
  border: none; border-radius: 4px; cursor: pointer;
  transition: background .15s ease-out, color .15s ease-out;
}
.segmented button:hover:not(:disabled):not(.on) { color: var(--text); }
.segmented button.on {
  background: var(--surface); color: var(--text);
  box-shadow: 0 1px 2px rgba(0,0,0,.08);
}
.segmented button:disabled { opacity: .45; cursor: not-allowed; }
.segmented-sm { margin: 0; }
.segmented-sm button { min-height: 28px; font-size: var(--fs-xs); }

/* ── buttons ────────────────────────────────────────────────── */

.btn {
  display: inline-flex; align-items: center; justify-content: center;
  gap: var(--s2);
  width: 100%; min-height: 44px;
  padding: var(--s2) var(--s4);
  font: inherit; font-size: var(--fs-md); font-weight: 500;
  border-radius: var(--radius); border: 1px solid transparent;
  cursor: pointer;
  transition: background .15s ease-out, border-color .15s ease-out;
}
.btn-primary { background: var(--primary); color: var(--on-primary); }
.btn-primary:hover:not(:disabled) { background: var(--primary-hover); }
.btn-ghost {
  background: var(--surface); color: var(--text);
  border-color: var(--border-strong);
}
.btn-ghost:hover:not(:disabled) { background: var(--surface-2); }
.btn:disabled { opacity: .45; cursor: not-allowed; }
.btn.working { pointer-events: none; }
.btn.working .btn-label::after {
  content: ""; display: inline-block;
  width: 13px; height: 13px; margin-left: var(--s2);
  vertical-align: -2px;
  border: 2px solid currentColor; border-right-color: transparent;
  border-radius: 50%;
  animation: spin .7s linear infinite;
}

/* ── readouts ───────────────────────────────────────────────── */

.readout { margin: 0 0 var(--s3); display: grid; gap: var(--s2); }
.readout div { display: flex; justify-content: space-between; gap: var(--s3); }
.readout dt { font-size: var(--fs-sm); color: var(--muted); }
.readout dd {
  margin: 0; text-align: right;
  font: 500 var(--fs-sm)/1.4 ui-monospace, SFMono-Regular, Menlo, monospace;
  font-variant-numeric: tabular-nums;
}

.empty {
  padding: var(--s3);
  margin-bottom: var(--s3);
  background: var(--surface-2);
  border-radius: var(--radius);
  font-size: var(--fs-sm);
}
.empty p { margin: 0 0 var(--s1); }
.empty p:last-child { margin: 0; color: var(--muted); }

/* ── workspace ──────────────────────────────────────────────── */

.workspace { display: flex; flex-direction: column; min-width: 0; }

.toolbar {
  display: flex; align-items: center; justify-content: space-between;
  gap: var(--s3);
  padding: var(--s2) var(--s4);
  border-bottom: 1px solid var(--border);
  background: var(--surface);
}
.toolbar .segmented { margin: 0; }
.toolbar > .segmented:first-child { min-width: 220px; }

.stage { position: relative; flex: 1; min-height: 0; }
.view { position: absolute; inset: 0; }
#three { background: var(--surface-2); }

.map-hint {
  position: absolute; left: var(--s4); bottom: var(--s4);
  margin: 0; padding: var(--s2) var(--s3);
  font-size: var(--fs-xs); color: var(--text);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  pointer-events: none;
}

.overlay-msg, .overlay-busy {
  position: absolute; inset: 0; z-index: 5;
  display: flex; flex-direction: column;
  align-items: center; justify-content: center;
  gap: var(--s3); padding: var(--s5);
  text-align: center;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(2px);
}
.overlay-msg p { margin: 0; max-width: 46ch; color: var(--muted); }
.overlay-msg h3 { font-size: var(--fs-lg); font-weight: 600; }
.overlay-msg .btn { width: auto; min-width: 140px; }
.overlay-error { background: color-mix(in srgb, var(--danger-bg) 94%, transparent); }
.overlay-error h3 { color: var(--danger); }

.spinner {
  width: 28px; height: 28px;
  border: 3px solid var(--border-strong);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin .8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

.warn-list {
  position: absolute; right: var(--s4); bottom: var(--s4);
  max-width: 320px; margin: 0; padding: var(--s3);
  list-style: none;
  font-size: var(--fs-xs); color: var(--warn);
  background: var(--surface);
  border: 1px solid var(--border); border-left: 3px solid var(--warn);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}
.warn-list li + li { margin-top: var(--s1); }

/* MapLibre overrides so the selection box reads clearly. */
.maplibregl-ctrl-attrib { font-size: 10px; }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
  }
}

/* ── narrow viewports ───────────────────────────────────────── */

@media (max-width: 860px) {
  .layout { grid-template-columns: 1fr; height: auto; }
  /* Selecting a region is the job; don't bury the map under the settings. */
  .workspace { order: -1; }
  .sidebar { border-right: none; }
  .workspace { border-bottom: 1px solid var(--border); }
  /* flex: 1 1 0% collapses to nothing once the workspace has auto height,
     so pin the basis rather than relying on the declared height. */
  .stage { flex: 0 0 60vh; height: 60vh; }
  /* The sidebar is not its own scroll container here, so sticky would float
     the button over the settings instead of pinning it. */
  .sticky-action { position: static; margin-top: var(--s4); }
  .topbar { flex-wrap: wrap; }
  .status { margin-left: 0; width: 100%; }
  .toolbar { flex-wrap: wrap; }
  .toolbar > .segmented:first-child { min-width: 0; flex: 1 1 100%; }
}