*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --bg: #f5f5f4;
  --surface: #ffffff;
  --accent: #2563eb;
  --accent-hover: #1d4ed8;
  --text: #1a1a1a;
  --muted: #9ca3af;
  --border: #e5e7eb;
  --empty: #e9e9e7;
  --radius-bubble: 50%;
}

body {
  font-family: system-ui, -apple-system, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100dvh;
}

/* ── Select page ── */

.select-page {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 4rem 1.5rem 3rem;
}

.page-title {
  font-size: clamp(3rem, 10vw, 6rem);
  font-weight: 900;
  letter-spacing: -0.03em;
  margin-bottom: 4rem;
  color: var(--text);
}

.grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  width: 100%;
  max-width: 640px;
  justify-items: center;
}

.tool-bubble {
  width: 160px;
  height: 160px;
  border-radius: var(--radius-bubble);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  transition: transform 0.15s, box-shadow 0.15s;
  text-decoration: none;
}

.tool-bubble.active {
  background: var(--accent);
  color: #fff;
  box-shadow: 0 4px 20px rgba(37, 99, 235, 0.35);
  cursor: pointer;
}

.tool-bubble.active:hover {
  transform: scale(1.06);
  background: var(--accent-hover);
  box-shadow: 0 6px 28px rgba(37, 99, 235, 0.45);
}

.tool-bubble.empty {
  background: var(--empty);
  cursor: default;
}

.tool-icon {
  font-size: 2rem;
  line-height: 1;
}

.tool-name {
  font-size: 0.85rem;
  font-weight: 600;
  text-align: center;
  line-height: 1.3;
  letter-spacing: 0.01em;
}

/* ── Tool page ── */

.tool-page {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 2rem 1.5rem 4rem;
}

.back-link {
  align-self: flex-start;
  color: var(--muted);
  text-decoration: none;
  font-size: 0.9rem;
  margin-bottom: 2.5rem;
  transition: color 0.15s;
}

.back-link:hover {
  color: var(--text);
}

.tool-card {
  background: var(--surface);
  border-radius: 1.25rem;
  padding: 2.5rem;
  width: 100%;
  max-width: 620px;
  box-shadow: 0 2px 12px rgba(0,0,0,0.07);
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.tool-card h1 {
  font-size: 1.5rem;
  font-weight: 800;
}

.tool-desc {
  color: var(--muted);
  font-size: 0.9rem;
  line-height: 1.5;
  margin-top: -0.5rem;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

label {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text);
}

input[type="number"],
select {
  border: 1.5px solid var(--border);
  border-radius: 0.6rem;
  padding: 0.65rem 0.85rem;
  font-size: 1rem;
  font-family: inherit;
  color: var(--text);
  background: var(--bg);
  outline: none;
  transition: border-color 0.15s;
  width: 100%;
}

input[type="number"]:focus,
select:focus {
  border-color: var(--accent);
}

.helling-row {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 0.5rem;
}

.helling-row select {
  width: auto;
}

button {
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 0.6rem;
  padding: 0.75rem 1.25rem;
  font-size: 1rem;
  font-weight: 700;
  font-family: inherit;
  cursor: pointer;
  transition: background 0.15s;
}

button:hover {
  background: var(--accent-hover);
}

.result {
  background: #eff6ff;
  border: 1.5px solid #bfdbfe;
  border-radius: 0.75rem;
  padding: 1.25rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.result-label {
  font-size: 0.875rem;
  color: #1e40af;
  font-weight: 600;
}

.result-right {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.result-value {
  font-size: 1.75rem;
  font-weight: 800;
  color: #1e40af;
}

.copy-btn {
  background: #dbeafe;
  color: #1e40af;
  border: none;
  border-radius: 0.5rem;
  padding: 0.35rem 0.75rem;
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s;
  white-space: nowrap;
}

.copy-btn:hover {
  background: #bfdbfe;
}

.error {
  background: #fef2f2;
  border: 1.5px solid #fecaca;
  border-radius: 0.75rem;
  padding: 0.85rem 1.1rem;
  font-size: 0.875rem;
  color: #dc2626;
}

/* ── Huis SVG ── */

#huis-svg {
  width: 100%;
  height: auto;
  display: block;
}

.muur-body {
  fill: #e8e3da;
  stroke: none;
}

.dak-body {
  fill: #d1d5db;
  stroke: none;
}

.dak-vlak {
  fill: #bfdbfe;
  opacity: 0.85;
}

.grond-lijn {
  stroke: #6b7280;
  stroke-width: 2.5;
  stroke-linecap: round;
}

.huis-lijn {
  stroke: #374151;
  stroke-width: 1.8;
  stroke-linecap: round;
  fill: none;
}

.goot-lijn {
  stroke-dasharray: 5 3;
  stroke: #6b7280;
}

.hartlijn {
  stroke: #d1d5db;
  stroke-width: 1.2;
  stroke-dasharray: 4 3;
  fill: none;
}

.dim-line {
  stroke: #9ca3af;
  stroke-width: 1;
  fill: none;
}

.pijl {
  fill: #9ca3af;
  stroke: none;
}

.dim-label {
  font-family: system-ui, sans-serif;
  font-size: 11px;
  fill: #4b5563;
  dominant-baseline: auto;
}

.dim-center {
  text-anchor: middle;
}

.dim-vert {
  text-anchor: middle;
}

.dak-label {
  font-family: system-ui, sans-serif;
  font-size: 11px;
  fill: #1e40af;
  font-weight: 700;
}

/* inputs naast elkaar op brede schermen */
.inputs {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.75rem;
}

@media (max-width: 420px) {
  .inputs {
    grid-template-columns: 1fr;
  }
}

/* ── Responsive ── */
@media (max-width: 480px) {
  .grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .tool-bubble {
    width: 130px;
    height: 130px;
  }
}