/* ─── Reset & base ─── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg:        #0f172a;
  --panel:     #1e293b;
  --panel2:    #263348;
  --border:    #334155;
  --accent:    #3b82f6;
  --accent2:   #1d4ed8;
  --success:   #22c55e;
  --danger:    #ef4444;
  --text:      #e2e8f0;
  --text-muted:#94a3b8;
  --radius:    8px;
  --shadow:    0 4px 24px rgba(0,0,0,.5);
}

html, body { height: 100%; background: var(--bg); color: var(--text);
             font-family: 'Segoe UI', system-ui, sans-serif; font-size: 14px; }

/* ─── Layout ─── */
#app { position: relative; width: 100vw; height: 100vh; overflow: hidden; }

#map { position: absolute; inset: 0; z-index: 1; }

/* ─── Panel ─── */
#panel {
  position: absolute; top: 12px; right: 12px; z-index: 10;
  width: 320px; max-height: calc(100vh - 24px);
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  display: flex; flex-direction: column;
  overflow: hidden;
}

#panel-header {
  padding: 14px 16px 10px;
  background: var(--panel2);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}
#panel-title   { display: block; font-size: 18px; font-weight: 700; color: var(--accent); }
#panel-subtitle{ display: block; font-size: 11px; color: var(--text-muted); margin-top: 2px; }

/* ─── Screens ─── */
.screen { display: none; flex-direction: column; gap: 10px;
          padding: 14px; overflow-y: auto; flex: 1; }
.screen.active { display: flex; }

/* ─── Buttons ─── */
.btn {
  display: block; width: 100%; padding: 9px 14px;
  border: none; border-radius: var(--radius);
  font-size: 13px; font-weight: 600; cursor: pointer;
  transition: filter .15s;
}
.btn:hover { filter: brightness(1.15); }
.btn-primary   { background: var(--accent);  color: #fff; }
.btn-secondary { background: var(--panel2); color: var(--text);
                 border: 1px solid var(--border); }
.btn-sm { width: auto; padding: 4px 10px; font-size: 12px;
          background: var(--panel2); color: var(--text);
          border: 1px solid var(--border); border-radius: 6px; cursor: pointer; }
.btn-sm:hover { filter: brightness(1.2); }

/* ─── Help text ─── */
.help-text { font-size: 12px; color: var(--text-muted); line-height: 1.5; }

/* ─── Map type select ─── */
.map-type-row { display: flex; align-items: center; gap: 8px; }
.map-type-row label { font-size: 12px; color: var(--text-muted); white-space: nowrap; }
.map-type-row select, select {
  flex: 1; padding: 6px 8px; border-radius: 6px;
  background: var(--panel2); color: var(--text);
  border: 1px solid var(--border); font-size: 12px;
}

/* ─── Tabs ─── */
.tab-bar { display: flex; gap: 4px; flex-shrink: 0; }
.tab-btn {
  flex: 1; padding: 7px 4px; border: 1px solid var(--border);
  border-radius: 6px; background: var(--panel2); color: var(--text-muted);
  font-size: 12px; cursor: pointer; transition: all .15s;
}
.tab-btn.active { background: var(--accent); color: #fff; border-color: var(--accent); }

.tab-content { display: none; flex-direction: column; gap: 10px; }
.tab-content.active { display: flex; }

/* ─── Tool row ─── */
.tool-row { display: flex; align-items: center; gap: 8px; }
.toggle-label { display: flex; align-items: center; gap: 8px; cursor: pointer; font-size: 13px; }
.toggle-label input[type=checkbox] { accent-color: var(--accent); width: 15px; height: 15px; }

.sep { border: none; border-top: 1px solid var(--border); }

/* ─── Coord row ─── */
.coord-row { display: grid; grid-template-columns: auto 1fr auto 1fr; gap: 6px; align-items: center; }
.coord-row label { font-size: 11px; color: var(--text-muted); }
.coord-row input { padding: 5px 6px; border-radius: 6px; background: var(--bg);
                   color: var(--text); border: 1px solid var(--border); font-size: 12px; width: 100%; }

/* ─── Action row ─── */
.action-row { display: flex; gap: 8px; }
.action-row .btn { flex: 1; }

/* ─── Param grid ─── */
.param-grid { display: grid; grid-template-columns: 1fr auto; gap: 6px 10px; align-items: center; }
.param-grid label { font-size: 12px; color: var(--text-muted); }
.param-grid input {
  width: 110px; padding: 7px 8px; border-radius: 6px;
  background: var(--bg); color: var(--text);
  border: 1px solid var(--border); font-size: 13px; text-align: right;
}

/* ─── Isolation entries ─── */
.isol-section { display: flex; flex-direction: column; gap: 6px; }
.isol-section > label { font-size: 12px; color: var(--text-muted); }
.isol-row { display: flex; gap: 6px; flex-wrap: wrap; }
.isol-entry {
  width: 75px; padding: 7px 8px; border-radius: 6px;
  background: var(--bg); color: var(--text);
  border: 1px solid var(--border); font-size: 13px; text-align: center;
}
.isol-btns { display: flex; gap: 12px; }

/* ─── Boiler list ─── */
.boiler-list { display: flex; flex-direction: column; gap: 8px; }
.boiler-item {
  display: grid; grid-template-columns: 1fr 70px 28px;
  gap: 12px; align-items: center;
}
.boiler-item label { font-size: 12px; }
.boiler-item input[type=number] {
  padding: 7px 8px; border-radius: 6px;
  background: var(--bg); color: var(--text);
  border: 1px solid var(--border); font-size: 13px; text-align: right;
}
.boiler-item input[type=checkbox] { accent-color: var(--accent); width: 16px; height: 16px; }

/* ─── Results screen ─── */
#results-header { font-weight: 600; font-size: 14px; }
.scenario-tabs { display: flex; gap: 4px; flex-wrap: wrap; }
.scenario-tab {
  padding: 5px 10px; border-radius: 6px; font-size: 12px; cursor: pointer;
  border: 1px solid var(--border); background: var(--panel2); color: var(--text-muted);
  transition: all .15s;
}
.scenario-tab.active { background: var(--accent); color: #fff; border-color: var(--accent); }

.slider-section { display: flex; flex-direction: column; gap: 6px; }
.slider-section label { font-size: 12px; color: var(--text-muted); }
.slider-section input[type=range] { width: 100%; accent-color: var(--accent); }
#step-label { font-size: 12px; color: var(--accent); font-weight: 600; }

.legend { display: flex; flex-direction: column; gap: 5px; }
.legend-item { display: flex; align-items: center; gap: 8px; font-size: 12px; }
.legend-swatch { width: 28px; height: 4px; border-radius: 2px; flex-shrink: 0; }

/* ─── Step stats (energy + length) ─── */
.step-stats {
  display: flex; gap: 12px; flex-wrap: wrap;
  padding: 8px 10px;
  background: var(--panel2); border: 1px solid var(--border);
  border-radius: var(--radius); font-size: 12px;
  min-height: 36px; align-items: center;
}
.step-stats:empty { display: none; }
.stat-item { color: var(--text-muted); }
.stat-item strong { color: var(--accent); font-size: 13px; }

/* ─── Progress overlay ─── */
#overlay {
  position: absolute; inset: 0; z-index: 100;
  background: rgba(15,23,42,.75); backdrop-filter: blur(4px);
  display: flex; align-items: center; justify-content: center;
}
#overlay.hidden { display: none; }

#overlay-card {
  background: var(--panel); border: 1px solid var(--border);
  border-radius: 12px; padding: 28px 32px;
  min-width: 320px; text-align: center; box-shadow: var(--shadow);
}
#overlay-title { font-size: 16px; font-weight: 700; margin-bottom: 16px; }
#progress-bar-wrap {
  height: 8px; background: var(--panel2); border-radius: 4px;
  overflow: hidden; margin-bottom: 12px;
}
#progress-bar {
  height: 100%; width: 0%; background: var(--accent);
  border-radius: 4px; transition: width .3s ease;
}
#overlay-message { font-size: 12px; color: var(--text-muted); min-height: 18px; }

/* ─── Toast ─── */
#toast {
  position: absolute; bottom: 20px; left: 50%; transform: translateX(-50%);
  z-index: 200; background: var(--panel2); color: var(--text);
  border: 1px solid var(--border); border-radius: 8px;
  padding: 10px 20px; font-size: 13px; box-shadow: var(--shadow);
  transition: opacity .3s;
}
#toast.hidden { display: none; }
#toast.error { border-color: var(--danger); color: var(--danger); }
#toast.success { border-color: var(--success); color: var(--success); }

/* ─── Mode hint box (bottom center) ─── */
#mode-hint-box {
  position: absolute; bottom: 20px; left: 50%; transform: translateX(-50%);
  z-index: 150; background: var(--panel); color: var(--text);
  border: 1px solid var(--accent); border-radius: 8px;
  padding: 12px 16px; font-size: 13px; box-shadow: var(--shadow);
  white-space: nowrap;
}
#mode-hint-box.hidden { display: none; }

/* ─── Tool mode buttons ─── */
.mode-btns { display: flex; flex-direction: column; gap: 6px; }
.btn-tool {
  display: block; width: 100%; padding: 8px 12px;
  border: 1px solid var(--border); border-radius: var(--radius);
  background: var(--panel2); color: var(--text-muted);
  font-size: 13px; font-weight: 500; cursor: pointer;
  text-align: left; transition: all .15s;
}
.btn-tool:hover { border-color: var(--accent); color: var(--text); }
.btn-tool.active {
  background: rgba(59,130,246,.15);
  border-color: var(--accent); color: var(--accent); font-weight: 600;
}
/* ─── Central placement overlay ─── */
#central-hint {
  position: absolute; bottom: 32px; left: 50%; transform: translateX(-50%);
  z-index: 500;
}
#central-hint.hidden { display: none; }
#central-hint-card {
  display: flex; align-items: center; gap: 12px;
  background: var(--panel); border: 1px solid var(--accent);
  border-radius: 10px; padding: 12px 18px;
  box-shadow: var(--shadow); font-size: 14px; font-weight: 600; color: var(--accent);
}
#central-hint-card button {
  padding: 5px 12px; border-radius: 6px;
  background: var(--panel2); color: var(--text-muted);
  border: 1px solid var(--border); cursor: pointer; font-size: 12px;
}

/* ─── Building modal ─── */
#building-modal {
  position: absolute; top: 50%; left: 50%;
  transform: translate(-50%, -50%); z-index: 300;
}
#building-modal.hidden { display: none; }
#building-modal-card {
  background: var(--panel); border: 1px solid var(--border);
  border-radius: 10px; box-shadow: var(--shadow);
  width: 280px; overflow: hidden;
}
.modal-header {
  display: flex; justify-content: space-between; align-items: center;
  padding: 12px 16px; background: var(--panel2);
  border-bottom: 1px solid var(--border); font-weight: 700;
}
.modal-close {
  background: none; border: none; color: var(--text-muted);
  font-size: 16px; cursor: pointer; padding: 0 4px;
}
.modal-close:hover { color: var(--danger); }
.modal-body { padding: 12px 16px; display: flex; flex-direction: column; gap: 7px; }
.bld-row { display: flex; justify-content: space-between; font-size: 12px; }
.bld-row label { color: var(--text-muted); }
.bld-row span { font-weight: 500; }
.modal-footer { padding: 10px 16px; border-top: 1px solid var(--border); }

/* ─── Draw hint ─── */
.draw-hint {
  text-align: center; padding: 10px 12px;
  background: rgba(59,130,246,.12);
  border: 1px dashed var(--accent);
  border-radius: var(--radius);
  font-size: 13px; color: var(--accent); font-weight: 600;
}

/* ─── Building filter ─── */
.filter-details {
  border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden;
}
.filter-details summary {
  padding: 8px 12px; background: var(--panel2);
  cursor: pointer; font-size: 12px; font-weight: 600;
  user-select: none; list-style: none;
}
.filter-details summary::-webkit-details-marker { display: none; }
.filter-details summary::before { content: '▶  '; font-size: 10px; }
.filter-details[open] summary::before { content: '▼  '; }
.filter-body { padding: 10px 12px; display: flex; flex-direction: column; gap: 6px; }
.filter-row {
  display: flex; align-items: center; gap: 8px;
  font-size: 12px; cursor: pointer; color: var(--text);
}
.filter-row input[type=checkbox] { accent-color: var(--accent); }
.filter-heating-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 4px 8px; }

/* ─── Add-building modal ─── */
#add-building-modal {
  position: absolute; top: 50%; left: 50%;
  transform: translate(-50%, -50%); z-index: 300;
}
#add-building-modal.hidden { display: none; }
#add-building-card {
  background: var(--panel); border: 1px solid var(--border);
  border-radius: 10px; box-shadow: var(--shadow); width: 300px; overflow: hidden;
}
.form-row {
  display: grid; grid-template-columns: 1fr auto; gap: 8px; align-items: center;
}
.form-row label { font-size: 12px; color: var(--text-muted); }
.form-row input, .form-row select {
  width: 130px; padding: 5px 7px; border-radius: 6px;
  background: var(--bg); color: var(--text);
  border: 1px solid var(--border); font-size: 12px;
}
.coords-display { font-size: 11px; color: var(--text-muted); text-align: right; }
.pick-btn { font-size: 12px; padding: 6px 10px; margin-top: 4px; }
.modal-footer-row { display: flex; gap: 8px; }
.modal-footer-row .btn { flex: 1; }

/* ─── License modal ─── */
#license-modal {
  position: absolute; top: 50%; left: 50%;
  transform: translate(-50%, -50%); z-index: 300;
}
#license-modal.hidden { display: none; }
#overlay-error.hidden { display: none; }
#license-modal-card {
  background: var(--panel); border: 1px solid var(--border);
  border-radius: 10px; box-shadow: var(--shadow); width: 320px; overflow: hidden;
}
#license-modal-card .modal-body p { font-size: 13px; line-height: 1.5; margin: 0; }
#license-modal-card .modal-body a { color: var(--accent); word-break: break-all; }

/* ─── Info indicators (hover tooltips via title attribute) ─── */
label i, button i, p i { color: var(--text-muted); margin-left: 2px; }

/* ─── Leaflet overrides ─── */
.leaflet-container { background: var(--bg); }
.leaflet-draw-toolbar a { background-color: var(--panel) !important; }