:root {
  --color-canvas: #f5f6f1;
  --color-surface: #ffffff;
  --color-surface-subtle: #f8f9f5;
  --color-text: #17201b;
  --color-muted: #66716b;
  --color-border: #dfe4dc;
  --color-border-strong: #c3ccc2;
  --color-primary: #006b57;
  --color-primary-hover: #005746;
  --color-accent: #a36a00;
  --color-error: #9f2d2d;
  --color-error-surface: #fff4f2;
  --shadow-panel: 0 18px 45px rgba(23, 32, 27, 0.08);
  --radius-sm: 6px;
  --radius-md: 8px;
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --font-body:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
  --motion-fast: 150ms ease;
}

* {
  box-sizing: border-box;
}

html {
  background: var(--color-canvas);
  color: var(--color-text);
  font-family: var(--font-body);
  line-height: 1.45;
}

body {
  margin: 0;
  min-width: 320px;
}

button,
input,
select {
  font: inherit;
}

button {
  cursor: pointer;
}

button:focus-visible,
input:focus-visible,
select:focus-visible {
  outline: 3px solid rgba(0, 107, 87, 0.24);
  outline-offset: 2px;
}

.app-shell {
  width: min(1440px, 100%);
  margin: 0 auto;
  padding: clamp(1rem, 3vw, 2rem);
}

.app-header {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: var(--space-5);
  align-items: end;
  margin-bottom: var(--space-6);
}

.eyebrow {
  margin: 0 0 var(--space-2);
  color: var(--color-primary);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h1,
h2,
p {
  margin-top: 0;
}

h1 {
  max-width: 12ch;
  margin-bottom: 0;
  font-size: clamp(2rem, 5vw, 4.75rem);
  line-height: 0.95;
}

h2 {
  margin-bottom: 0;
  font-size: 1rem;
}

.header-metric {
  min-width: 230px;
  padding: var(--space-4);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-surface);
  box-shadow: var(--shadow-panel);
}

.header-metric span,
.summary-tile span {
  display: block;
  color: var(--color-muted);
  font-size: 0.78rem;
  font-weight: 700;
  text-transform: uppercase;
}

.header-metric strong {
  display: block;
  margin-top: var(--space-1);
  font-size: 1.45rem;
}

.workspace {
  display: grid;
  grid-template-columns: minmax(280px, 360px) minmax(0, 1fr);
  gap: var(--space-6);
  align-items: start;
}

.input-panel,
.summary-tile,
.table-section,
.notice {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-surface);
  box-shadow: var(--shadow-panel);
}

.input-panel {
  position: sticky;
  top: var(--space-4);
  padding: var(--space-5);
}

.panel-heading,
.section-heading {
  display: flex;
  gap: var(--space-4);
  align-items: center;
  justify-content: space-between;
}

.panel-heading {
  margin-bottom: var(--space-5);
}

.secondary-button {
  min-height: 2.25rem;
  padding: 0 var(--space-3);
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  color: var(--color-text);
  font-size: 0.85rem;
  font-weight: 700;
  transition:
    border-color var(--motion-fast),
    color var(--motion-fast);
}

.secondary-button:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.icon-button {
  display: inline-grid;
  width: 2.5rem;
  height: 2.5rem;
  flex: 0 0 2.5rem;
  place-items: center;
  padding: 0;
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  color: var(--color-text);
  font-size: 1.25rem;
  font-weight: 800;
  line-height: 1;
  transition:
    border-color var(--motion-fast),
    background var(--motion-fast),
    color var(--motion-fast);
}

.icon-button:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

fieldset {
  min-width: 0;
  margin: 0;
  padding: var(--space-5) 0 0;
  border: 0;
}

fieldset + fieldset {
  margin-top: var(--space-5);
  border-top: 1px solid var(--color-border);
}

legend {
  margin-bottom: var(--space-3);
  color: var(--color-accent);
  font-size: 0.78rem;
  font-weight: 800;
  text-transform: uppercase;
}

.input-row {
  display: grid;
  gap: var(--space-2);
  margin-bottom: var(--space-4);
}

.input-row:last-child {
  margin-bottom: 0;
}

label {
  color: var(--color-muted);
  font-size: 0.9rem;
  font-weight: 700;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.input-with-suffix {
  position: relative;
}

input,
select {
  width: 100%;
  min-height: 2.85rem;
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  color: var(--color-text);
  transition:
    border-color var(--motion-fast),
    box-shadow var(--motion-fast);
}

input {
  padding: 0.65rem 0.75rem;
}

select {
  padding: 0.65rem 0.75rem;
}

.input-with-suffix input {
  padding-right: 2.7rem;
}

.input-with-suffix span {
  position: absolute;
  top: 50%;
  right: var(--space-3);
  color: var(--color-muted);
  font-weight: 800;
  transform: translateY(-50%);
}

input:hover,
select:hover {
  border-color: var(--color-primary);
}

.coefficient-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  margin-bottom: var(--space-3);
}

.coefficient-heading > span {
  color: var(--color-muted);
  font-size: 0.9rem;
  font-weight: 700;
}

.add-coefficient {
  border-color: var(--color-primary);
  background: var(--color-primary);
  color: #ffffff;
}

.add-coefficient:hover {
  background: var(--color-primary-hover);
  color: #ffffff;
}

.coefficient-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 2.5rem;
  gap: var(--space-2);
  margin-bottom: var(--space-2);
}

.coefficient-row:last-child {
  margin-bottom: 0;
}

.remove-coefficient {
  color: var(--color-muted);
}

.results-stack {
  display: grid;
  gap: var(--space-5);
  min-width: 0;
}

#results {
  display: grid;
  gap: var(--space-5);
}

[hidden] {
  display: none !important;
}

.tab-switch {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-2);
  padding: var(--space-2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-surface);
}

.tab-switch button {
  min-height: 2.75rem;
  border: 0;
  border-radius: var(--radius-sm);
  background: transparent;
  color: var(--color-muted);
  font-weight: 800;
  transition:
    background var(--motion-fast),
    color var(--motion-fast);
}

.tab-switch button:hover,
.tab-switch button.active {
  background: var(--color-primary);
  color: #ffffff;
}

.summary-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: var(--space-4);
}

.summary-tile {
  min-height: 8.25rem;
  padding: var(--space-4);
}

.summary-tile strong {
  display: block;
  margin: var(--space-3) 0 var(--space-2);
  font-size: clamp(1.25rem, 2vw, 1.75rem);
  line-height: 1.05;
}

.summary-tile small,
th small {
  display: block;
  color: var(--color-muted);
  font-size: 0.78rem;
  font-weight: 600;
}

.table-section {
  overflow: hidden;
}

.section-heading {
  padding: var(--space-5);
  border-bottom: 1px solid var(--color-border);
}

.section-heading p {
  margin: 0;
  color: var(--color-muted);
  font-size: 0.9rem;
  font-weight: 700;
}

.table-scroll {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
}

.offer-table {
  min-width: 660px;
}

.ask-table {
  min-width: 440px;
}

th,
td {
  padding: 0.95rem var(--space-4);
  border-bottom: 1px solid var(--color-border);
  text-align: right;
  vertical-align: top;
  white-space: nowrap;
}

thead th {
  background: var(--color-surface-subtle);
  color: var(--color-muted);
  font-size: 0.78rem;
  font-weight: 800;
  text-transform: uppercase;
}

tbody tr:last-child th,
tbody tr:last-child td {
  border-bottom: 0;
}

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

tbody th {
  font-weight: 800;
}

tbody th span {
  display: block;
}

.strong-cell {
  font-weight: 900;
}

.notice {
  padding: var(--space-5);
}

.notice dl {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-4);
  margin: 0;
}

.notice dt {
  color: var(--color-accent);
  font-size: 0.78rem;
  font-weight: 900;
  text-transform: uppercase;
}

.notice dd {
  margin: var(--space-1) 0 0;
  color: var(--color-muted);
}

.error-panel {
  border-color: rgba(159, 45, 45, 0.32);
  background: var(--color-error-surface);
  color: var(--color-error);
}

.error-panel ul {
  margin: var(--space-3) 0 0;
  padding-left: var(--space-5);
}

@media (max-width: 1120px) {
  .app-header {
    align-items: stretch;
  }

  .workspace {
    grid-template-columns: 1fr;
  }

  .input-panel {
    position: static;
  }

  .summary-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 720px) {
  .app-shell {
    padding: var(--space-4);
  }

  .app-header {
    grid-template-columns: 1fr;
  }

  h1 {
    max-width: 10ch;
    font-size: 2.65rem;
  }

  .header-metric {
    min-width: 0;
  }

  .panel-heading,
  .section-heading {
    align-items: flex-start;
    flex-direction: column;
  }

  .summary-grid,
  .notice dl {
    grid-template-columns: 1fr;
  }

  .tab-switch {
    grid-template-columns: 1fr;
  }

  .summary-tile {
    min-height: 0;
  }

  th,
  td {
    padding: 0.85rem var(--space-3);
  }
}