:root {
  color-scheme: light;
  font-family: 'Inter', 'Segoe UI', system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
  --bg: #ffffff;
  --fg: rgba(0, 0, 0, 0.9);
  --muted: rgba(0, 0, 0, 0.6);
  --accent: #111;
  --border: rgba(0, 0, 0, 0.12);
  --radius: 16px;
  --shadow: 0 18px 42px rgba(0, 0, 0, 0.08);
}

* {
  box-sizing: border-box;
}

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

.app {
  display: grid;
  gap: clamp(1.5rem, 3vw, 2.5rem);
  padding: clamp(1.5rem, 3vw, 3rem);
  max-width: 1080px;
  margin: 0 auto;
}

.app__header {
  display: flex;
  flex-direction: column;
  gap: clamp(1rem, 2vw, 1.5rem);
}

.app__header h1 {
  font-size: clamp(2rem, 5vw, 3rem);
  margin: 0;
}

.app__header p {
  margin: 0;
  color: var(--muted);
  max-width: 42ch;
}

.unit-toggle {
  display: inline-flex;
  border: 1px solid var(--border);
  border-radius: 999px;
  overflow: hidden;
  background: rgba(0, 0, 0, 0.04);
}

.unit-toggle__btn {
  appearance: none;
  border: none;
  padding: 0.6rem 1.2rem;
  background: transparent;
  color: var(--muted);
  font: inherit;
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease;
}

.unit-toggle__btn--active {
  background: var(--fg);
  color: var(--bg);
}

.panel {
  background: rgba(255, 255, 255, 0.78);
  border: 1px solid rgba(0, 0, 0, 0.06);
  border-radius: var(--radius);
  padding: clamp(1.25rem, 3vw, 2rem);
  box-shadow: var(--shadow);
  backdrop-filter: blur(6px);
}

.panel--visual {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.panel__title {
  margin: 0;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 0.82rem;
  color: var(--muted);
}

.form {
  display: grid;
  gap: 1.5rem;
}

.form__group {
  border: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.9rem;
}

.form__group legend {
  font-weight: 600;
  margin-bottom: 0.4rem;
}

.form__item {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.form__item span {
  color: var(--muted);
  font-size: 0.95rem;
}

.form__item input {
  padding: 0.65rem 0.8rem;
  border-radius: 14px;
  border: 1px solid var(--border);
  font-size: 1rem;
  background: rgba(255, 255, 255, 0.9);
}

.form__item input:focus {
  outline: 2px solid rgba(0, 0, 0, 0.5);
  outline-offset: 2px;
}

.form__item select {
  padding: 0.65rem 2.6rem 0.65rem 0.8rem;
  border-radius: 14px;
  border: 1px solid var(--border);
  font-size: 1rem;
  background: rgba(255, 255, 255, 0.9)
    url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='10' height='6' viewBox='0 0 10 6'%3E%3Cpath fill='%23333' d='M1 0l4 4 4-4 1 1-5 5-5-5z'/%3E%3C/svg%3E")
    no-repeat right 0.9rem center;
  background-size: 10px 6px;
  appearance: none;
  -webkit-appearance: none;
  -moz-appearance: none;
  cursor: pointer;
}

.form__item select:focus {
  outline: 2px solid rgba(0, 0, 0, 0.5);
  outline-offset: 2px;
}

.form__item select::-ms-expand {
  display: none;
}

.form__submit {
  justify-self: start;
  padding: 0.75rem 1.6rem;
  border-radius: 999px;
  border: none;
  background: var(--fg);
  color: var(--bg);
  font-size: 1rem;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.form__submit:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 24px rgba(0, 0, 0, 0.18);
}

.results {
  display: grid;
  gap: 1.2rem;
}

.results__item {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  border-bottom: 1px solid rgba(0, 0, 0, 0.08);
  padding-bottom: 0.6rem;
}

.results__label {
  color: var(--muted);
  font-size: 0.95rem;
}

.results__value {
  font-size: clamp(1.35rem, 4vw, 1.8rem);
  font-variant-numeric: tabular-nums;
}

.results__stack {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 0.2rem;
}

.results__meta {
  font-size: 0.75rem;
  color: var(--muted);
  font-variant-numeric: tabular-nums;
}

.cuts {
  display: grid;
  gap: 1.5rem;
}

.cuts--grid {
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.5rem;
}

.cuts__group {
  display: grid;
  gap: 0.8rem;
}

.cuts__header {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}

.cuts__heading {
  margin: 0;
  font-size: 0.95rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.cuts__meta {
  margin: 0;
  font-size: 0.85rem;
  color: var(--muted);
}

.cuts__table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
  border: 1px solid rgba(0, 0, 0, 0.08);
  border-radius: 12px;
  overflow: hidden;
  background: rgba(255, 255, 255, 0.9);
}

.cuts__table thead {
  background: rgba(0, 0, 0, 0.05);
  text-transform: uppercase;
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  color: var(--muted);
}

.cuts__table th,
.cuts__table td {
  padding: 0.6rem 0.75rem;
  text-align: right;
  border-bottom: 1px solid rgba(0, 0, 0, 0.08);
  font-variant-numeric: tabular-nums;
}

.cuts__table th:first-child,
.cuts__table td:first-child {
  text-align: left;
}

.cuts__table tbody tr:nth-child(even) {
  background: rgba(0, 0, 0, 0.03);
}

.cuts__table tbody tr:last-child td {
  border-bottom: none;
}

.cuts__table--insulation td:first-child {
  max-width: 160px;
  word-break: break-word;
}

.cuts__empty {
  color: var(--muted);
  font-size: 0.85rem;
  padding: 0.75rem;
}

.cuts__warnings {
  margin-top: 1rem;
  color: #b20000;
  font-size: 0.9rem;
  line-height: 1.4;
}

.visual {
  position: relative;
  width: 100%;
  min-height: 260px;
  border-radius: 12px;
  border: 1px dashed rgba(0, 0, 0, 0.15);
  overflow: hidden;
  background: linear-gradient(135deg, rgba(0, 0, 0, 0.02), rgba(0, 0, 0, 0.05));
  padding: 18px;
}

.visual__svg {
  width: 100%;
  height: 100%;
  display: block;
}

.visual__background {
  fill: rgba(255, 255, 255, 0.85);
}

.visual__cavity {
  fill: rgba(0, 0, 0, 0.06);
  stroke: rgba(0, 0, 0, 0.12);
  stroke-width: 1;
  stroke-dasharray: 8 6;
}

.visual__insulation-piece {
  fill: rgba(255, 215, 80, 0.38);
  stroke: rgba(200, 140, 0, 0.85);
  stroke-width: 0.9;
  cursor: help;
}

.visual__insulation-piece[data-trim-width],
.visual__insulation-piece[data-trim-height] {
  stroke-dasharray: 6 4;
}

.visual__insulation-piece[data-gap-width] {
  fill: rgba(255, 170, 0, 0.2);
  stroke: rgba(255, 120, 0, 0.85);
}

.visual__insulation-piece[data-trim-height='trim-top'] {
  stroke-linecap: square;
}

.visual__insulation-piece[data-trim-height='trim-bottom'] {
  stroke-linecap: square;
}

.visual__insulation-seam {
  stroke: rgba(140, 95, 0, 0.9);
  stroke-width: 1.2;
  stroke-dasharray: 5 4;
  pointer-events: none;
}

.visual__block {
  fill: rgba(0, 0, 0, 0.55);
  stroke: rgba(0, 0, 0, 0.2);
  stroke-width: 0.5;
  stroke-linecap: round;
}

.visual__block[data-offset='up'] {
  fill: rgba(0, 0, 0, 0.45);
}

.visual__block[data-offset='down'] {
  fill: rgba(0, 0, 0, 0.65);
}

.visual__block[data-trim='bottom'] {
  stroke: rgba(0, 0, 0, 0.35);
}

.visual__block[data-trim='top'] {
  stroke: rgba(255, 255, 255, 0.25);
}

.visual__block-label {
  fill: #fff;
  font-size: 12px;
  text-anchor: middle;
  dominant-baseline: middle;
  pointer-events: none;
  font-weight: 600;
  letter-spacing: 0.08em;
}

.visual__stud-shape {
  fill: rgba(0, 0, 0, 0.88);
}

.visual__plate-piece {
  fill: rgba(0, 0, 0, 0.78);
  cursor: help;
}

.visual__plate-piece--top {
  stroke: rgba(255, 255, 255, 0.18);
  stroke-width: 0.6;
}

.visual__plate-piece--bottom {
  stroke: rgba(0, 0, 0, 0.25);
  stroke-width: 0.6;
}

.visual__label {
  position: absolute;
  font-size: 0.75rem;
  color: var(--muted);
  background: rgba(255, 255, 255, 0.85);
  padding: 0.15rem 0.45rem;
  border-radius: 999px;
  backdrop-filter: blur(6px);
}

.visual__label--width {
  bottom: 6px;
  left: 50%;
  transform: translateX(-50%);
}

.visual__label--height {
  top: 50%;
  left: 6px;
  transform: translateY(-50%) rotate(-90deg);
  transform-origin: left top;
}

.visual__tooltip {
  position: absolute;
  pointer-events: none;
  background: rgba(20, 20, 20, 0.88);
  color: #fff;
  padding: 0.25rem 0.45rem;
  border-radius: 6px;
  font-size: 0.74rem;
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.02em;
  transform: translate(-50%, -120%);
  opacity: 0;
  transition: opacity 0.12s ease;
  z-index: 5;
  white-space: nowrap;
}

.visual__tooltip::after {
  content: '';
  position: absolute;
  left: 50%;
  bottom: -4px;
  width: 8px;
  height: 8px;
  background: inherit;
  transform: translateX(-50%) rotate(45deg);
  border-radius: 1px;
}

.app__footer {
  color: var(--muted);
  font-size: 0.8rem;
}

@keyframes visual-enter {
  from {
    opacity: 0;
    transform: scale(0.98);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

@media (min-width: 1024px) {
  .app {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .app__header,
  .panel--cuts,
  .panel--visual,
  .app__footer {
    grid-column: 1 / -1;
  }

  .cuts--grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}