.calc-shell {
  width: min(1120px, calc(100% - 40px));
  margin: 0 auto;
  padding: 54px 0 70px;
}

.calc-hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 320px;
  gap: 28px;
  align-items: end;
  margin-bottom: 28px;
}

.calc-hero h1 {
  font-size: clamp(42px, 7vw, 76px);
}

.calc-hero p {
  max-width: 780px;
  margin: 14px 0 0;
  color: var(--muted);
  font-size: 17px;
}

.formula-card,
.calculator-panel,
.result-panel {
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--surface);
  box-shadow: var(--shadow);
}

.formula-card {
  padding: 20px;
}

.formula-card span,
.result-header span,
.calc-field span,
.result-details span {
  color: var(--muted);
  font-size: 13px;
  font-weight: 800;
}

.formula-card strong {
  display: block;
  margin: 8px 0;
  font-size: 30px;
}

.formula-card p {
  margin: 0;
  font-size: 14px;
}

.calculator-grid {
  display: grid;
  grid-template-columns: minmax(360px, 0.85fr) minmax(360px, 1.15fr);
  gap: 22px;
  align-items: start;
}

.calculator-panel,
.result-panel {
  padding: 22px;
}

.calc-field {
  display: grid;
  gap: 8px;
}

.calc-field + .calc-field,
.field-row,
.quick-row,
.action-row {
  margin-top: 16px;
}

.field-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 150px;
  gap: 12px;
}

.calc-field input,
.calc-field select {
  width: 100%;
  height: 46px;
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 0 12px;
  background: #fff;
  color: var(--ink);
  font: inherit;
  outline: none;
}

.calc-field input:focus,
.calc-field select:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(15, 118, 110, 0.14);
}

.quick-row {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 8px;
}

.quick-row button {
  min-height: 38px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--surface-soft);
  color: var(--ink);
  cursor: pointer;
  font-weight: 800;
}

.quick-row button:hover {
  border-color: rgba(15, 118, 110, 0.42);
}

.action-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.primary-button,
.ghost-button {
  min-height: 42px;
  border-radius: 6px;
  padding: 0 16px;
  cursor: pointer;
  font: inherit;
  font-weight: 800;
}

.primary-button {
  border: 1px solid transparent;
  background: var(--accent);
  color: #fff;
}

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

.ghost-button {
  border: 1px solid var(--line);
  background: var(--surface-soft);
  color: var(--ink);
}

.ghost-button:disabled {
  cursor: not-allowed;
  opacity: 0.58;
}

.result-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--line);
}

.result-header strong {
  color: var(--accent-strong);
}

.result-main {
  padding: 30px 0;
}

.result-main p {
  margin: 0 0 8px;
  color: var(--muted);
  font-weight: 800;
}

.result-main strong {
  display: block;
  font-size: clamp(46px, 8vw, 84px);
  line-height: 1;
}

.result-main span {
  display: block;
  margin-top: 10px;
  color: var(--muted);
}

.result-details {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--line);
}

.result-details div {
  min-height: 76px;
  padding: 12px;
  background: var(--surface-soft);
}

.result-details strong {
  display: block;
  margin-top: 4px;
  overflow-wrap: anywhere;
}

.copy-row {
  margin-top: 16px;
}

.calc-note {
  margin: 16px 0 0;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.55;
}

@media (max-width: 900px) {
  .calc-shell {
    width: min(100% - 28px, 1120px);
  }

  .calc-hero,
  .calculator-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 620px) {
  .field-row,
  .quick-row,
  .result-details {
    grid-template-columns: 1fr;
  }

  .calc-hero h1 {
    font-size: 38px;
  }
}