:root {
  --bg:        #0f1419;
  --surface:   #171d26;
  --surface-2: #1e2530;
  --border:    #2a3341;
  --text:      #e6e9ef;
  --muted:     #8b96a5;
  --piek:      #f0a83c;   /* amber — piekuren */
  --dal:       #4fd1c5;   /* cyaan — daluren */
  --bad:       #e2645b;
  --radius: 8px;
  --font-ui: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: "SF Mono", "IBM Plex Mono", ui-monospace, "Cascadia Code", Consolas, monospace;
}

* { box-sizing: border-box; }

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

/* ---------- Header ---------- */
.topbar {
  border-bottom: 1px solid var(--border);
  background: linear-gradient(180deg, var(--surface), var(--bg));
}
.topbar-inner {
  max-width: 1080px;
  margin: 0 auto;
  padding: 28px 24px 20px;
  display: flex;
  align-items: center;
}
.merk { display: flex; align-items: center; gap: 16px; }
.merk-pulslijn svg { width: 64px; height: 20px; }
.merk-pulslijn polyline {
  fill: none;
  stroke: var(--piek);
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}
h1 {
  margin: 0;
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -0.01em;
}
.submerk {
  margin: 2px 0 0;
  color: var(--muted);
  font-size: 13px;
}

/* ---------- Tabs ---------- */
.tabs {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  gap: 4px;
  border-bottom: 1px solid var(--border);
  overflow-x: auto;
}
.tab-knop {
  background: none;
  border: none;
  color: var(--muted);
  font-family: var(--font-ui);
  font-size: 14px;
  font-weight: 600;
  padding: 14px 16px;
  cursor: pointer;
  border-bottom: 2px solid transparent;
  white-space: nowrap;
}
.tab-knop:hover { color: var(--text); }
.tab-knop.actief { color: var(--piek); border-bottom-color: var(--piek); }

main {
  max-width: 1080px;
  margin: 0 auto;
  padding: 24px;
}
.tab-paneel { display: none; }
.tab-paneel.actief { display: block; }

/* ---------- Panels ---------- */
.paneel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px 24px;
  margin-bottom: 20px;
}
.paneel h2 {
  margin: 0 0 12px;
  font-size: 16px;
  font-weight: 700;
}
.uitleg {
  color: var(--muted);
  font-size: 14px;
  margin: 0 0 16px;
  max-width: 640px;
}
.uitleg-klein {
  color: var(--muted);
  font-size: 12.5px;
  margin: 10px 0 0;
}
.uitleg-lijst {
  color: var(--muted);
  font-size: 14px;
  padding-left: 20px;
}
.uitleg-lijst li { margin-bottom: 10px; }
.uitleg-lijst strong { color: var(--text); }
a { color: var(--dal); }
.leeg { color: var(--muted); font-size: 14px; font-style: italic; }

/* ---------- Inputs / buttons ---------- */
.bestand-knop {
  display: inline-block;
  background: var(--piek);
  color: #1a1206;
  font-weight: 700;
  font-size: 14px;
  padding: 10px 18px;
  border-radius: var(--radius);
  cursor: pointer;
}
.bestand-knop input { display: none; }
.knop-secundair {
  background: var(--surface-2);
  border: 1px solid var(--border);
  color: var(--text);
  font-family: var(--font-ui);
  font-size: 13px;
  font-weight: 600;
  padding: 9px 16px;
  border-radius: var(--radius);
  cursor: pointer;
  margin-top: 14px;
}
.knop-secundair:hover { border-color: var(--dal); }

.status { font-size: 13px; margin-top: 12px; }
.status.ok { color: var(--dal); }
.status.error { color: var(--bad); }
.waarschuwing {
  background: rgba(226, 100, 91, 0.1);
  border: 1px solid rgba(226, 100, 91, 0.3);
  color: #f4a29c;
  font-size: 13px;
  padding: 10px 14px;
  border-radius: var(--radius);
  margin-bottom: 14px;
}

.instellingen-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 14px;
}
.instellingen-grid label,
.kolom-mapping .map-veld {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 12.5px;
  color: var(--muted);
  font-weight: 600;
}
input[type="number"], input[type="text"], select {
  background: var(--surface-2);
  border: 1px solid var(--border);
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 13px;
  padding: 8px 10px;
  border-radius: 6px;
}
input:focus, select:focus, .tab-knop:focus-visible, .bestand-knop:focus-within {
  outline: 2px solid var(--dal);
  outline-offset: 1px;
}

.kolom-mapping {
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 14px;
}

/* ---------- Tables ---------- */
.tabel-scroll { overflow-x: auto; }
table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--font-mono);
  font-size: 13px;
}
th, td {
  padding: 9px 12px;
  text-align: right;
  border-bottom: 1px solid var(--border);
  white-space: nowrap;
}
th { color: var(--muted); font-weight: 600; text-transform: uppercase; font-size: 11px; letter-spacing: 0.02em; }
td.maand-cel, th:first-child { text-align: left; }
.maand-cel { color: var(--text); font-weight: 600; }
tfoot td { border-top: 2px solid var(--border); border-bottom: none; color: var(--piek); }
td.onbekend { color: var(--muted); }
.belpex-input { width: 100px; text-align: right; }

/* ---------- Formula block ---------- */
.formule {
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  overflow-x: auto;
  color: var(--dal);
}

.footer {
  max-width: 1080px;
  margin: 0 auto;
  padding: 8px 24px 40px;
  color: var(--muted);
  font-size: 12px;
}

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

@media (max-width: 640px) {
  .topbar-inner { padding: 20px 16px; }
  main { padding: 16px; }
  .paneel { padding: 16px; }
}