/* ============================================================
   3ТЭК · Инженерные калькуляторы
   ============================================================ */

.calc-head .lead { max-width: 820px; }
.calc-sec { padding-top: 6px; }

.calc {
  display: grid; grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr);
  gap: 28px; align-items: start;
}

/* ---------- форма ---------- */
.calc-form {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 22px 24px 8px; box-shadow: var(--shadow-sm);
}
.calc-modes {
  display: flex; flex-wrap: wrap; gap: 6px; padding: 5px; margin-bottom: 18px;
  background: var(--mist); border: 1px solid var(--line); border-radius: 12px;
}
.calc-modes button {
  flex: 1 1 150px; border: 0; background: transparent; cursor: pointer;
  font: 600 14px/1.25 var(--font-body); color: var(--muted);
  padding: 10px 12px; border-radius: 9px; transition: background .15s, color .15s, box-shadow .15s;
}
.calc-modes button:hover { color: var(--ink); }
.calc-modes button.is-on { background: #fff; color: var(--ink); box-shadow: var(--shadow-sm); }
.calc-modes button:focus-visible { outline: 2px solid var(--blue); outline-offset: 2px; }

.calc-group { border: 0; margin: 0 0 16px; padding: 0; min-width: 0; }
.calc-group[hidden], .calc-field[hidden] { display: none !important; }
.calc-group legend {
  font-family: var(--font-mono); font-size: 11.5px; font-weight: 600; letter-spacing: .12em;
  text-transform: uppercase; color: var(--copper-deep); margin-bottom: 12px; padding: 0;
}
.calc-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 14px 16px; }
.calc-field { display: flex; flex-direction: column; gap: 6px; min-width: 0; }
.calc-field label { font-size: 13.5px; font-weight: 600; color: var(--ink-soft); line-height: 1.35; }
.calc-unit { font-weight: 400; color: var(--muted); white-space: nowrap; }
.calc-field .input { width: 100%; font-variant-numeric: tabular-nums; }
.calc-help { font-size: 12.5px; line-height: 1.45; color: var(--muted); }

/* ---------- результат ---------- */
.calc-out {
  position: sticky; top: 96px;
  background: var(--ink); color: #dbe6f3; border-radius: var(--radius);
  padding: 20px 22px 18px; box-shadow: var(--shadow);
}
.calc-out-head { display: flex; justify-content: space-between; align-items: baseline; gap: 10px; margin-bottom: 10px; }
.calc-out-head b { font-family: var(--font-display); font-size: 17px; color: #fff; font-weight: 600; }
.calc-out-head span { font-family: var(--font-mono); font-size: 11px; letter-spacing: .08em; text-transform: uppercase; color: #7b8ea8; }
.calc-row {
  display: flex; justify-content: space-between; align-items: baseline; gap: 14px;
  padding: 9px 0; border-bottom: 1px solid rgba(255, 255, 255, .08);
}
.calc-row span { font-size: 13.5px; line-height: 1.4; color: #a9bad0; }
.calc-row b { font-family: var(--font-mono); font-size: 15px; font-weight: 600; color: #fff; text-align: right; white-space: nowrap; font-variant-numeric: tabular-nums; }
.calc-row b small { font-family: var(--font-body); font-size: 12.5px; font-weight: 400; color: #a9bad0; white-space: normal; }
.calc-row.is-key span { color: #e6eef8; }
.calc-row.is-key b { font-size: 21px; color: #ffb366; }
.calc-notes { margin-top: 14px; display: grid; gap: 8px; }
.calc-note { margin: 0; padding: 10px 12px; border-radius: 9px; font-size: 13.5px; line-height: 1.5; border-left: 3px solid; }
.calc-note.is-info { background: rgba(78, 168, 255, .1); border-color: #4ea8ff; color: #d4e7fb; }
.calc-note.is-ok { background: rgba(47, 211, 106, .1); border-color: #2fd36a; color: #d3f5df; }
.calc-note.is-warn { background: rgba(255, 179, 102, .12); border-color: #ffb366; color: #ffe6cc; }
.calc-note.is-danger { background: rgba(255, 90, 79, .14); border-color: #ff5a4f; color: #ffd9d6; }
.calc-steps { margin-top: 14px; border-top: 1px solid rgba(255, 255, 255, .08); padding-top: 10px; }
.calc-steps summary { cursor: pointer; font-size: 13.5px; font-weight: 600; color: #9fd0ff; }
.calc-steps ol { margin: 10px 0 0; padding-left: 20px; display: grid; gap: 6px; }
.calc-steps li { font-family: var(--font-mono); font-size: 12px; line-height: 1.55; color: #c7d5e6; word-break: break-word; }
.calc-actions { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 16px; }
.calc-actions .btn-outline { background: transparent; color: #fff; border-color: rgba(255, 255, 255, .28); }
.calc-actions .btn-outline:hover { border-color: #fff; }
.calc-actions [hidden] { display: none !important; }
.calc-disc { margin: 14px 0 0; font-size: 12px; line-height: 1.5; color: #7b8ea8; }

/* ---------- статья под калькулятором ---------- */
.calc-art h2 { margin-top: 36px; }
.calc-art h2:first-child { margin-top: 0; }
.calc-f {
  font-family: var(--font-mono); font-size: .9em; background: var(--mist); border: 1px solid var(--line);
  border-radius: 6px; padding: 1px 6px; white-space: nowrap;
}
.calc-fb {
  font-family: var(--font-mono); font-size: 15px; background: var(--mist); border-left: 3px solid var(--copper);
  border-radius: 0 10px 10px 0; padding: 12px 16px; overflow-x: auto; color: var(--ink);
}
.calc-ex { display: grid; grid-template-columns: 1fr; gap: 18px; margin: 14px 0; }
.calc-field.is-wide { grid-column: 1 / -1; }
.calc-art .faq-list { display: grid; gap: 10px; }
.calc-table { width: 100%; border-collapse: collapse; font-size: 14px; }
.calc-table th { text-align: left; font-family: var(--font-mono); font-size: 11px; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); padding: 8px 10px; border-bottom: 2px solid var(--line); }
.calc-table td { padding: 8px 10px; border-bottom: 1px solid var(--line); vertical-align: top; }
.calc-table td:last-child { text-align: right; white-space: nowrap; font-variant-numeric: tabular-nums; }
.calc-ex-steps { font-family: var(--font-mono); font-size: 13px; line-height: 1.6; color: var(--ink-soft); padding-left: 22px; }
.calc-ex-steps li { margin-bottom: 4px; word-break: break-word; }
.calc-src, .calc-rel { padding-left: 20px; }
.calc-src li, .calc-rel li { margin-bottom: 8px; line-height: 1.5; }
.calc-src a, .calc-rel a { color: var(--blue-deep); text-decoration: underline; text-underline-offset: 2px; }

/* ---------- меню калькуляторов ---------- */
.calc-cat { font-size: clamp(19px, 2vw, 24px); margin: 34px 0 14px; }
.calc-cat:first-child { margin-top: 8px; }
.calc-cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 16px; }
.calc-card {
  display: flex; flex-direction: column; gap: 8px; padding: 20px 20px 18px;
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  text-decoration: none; color: var(--ink); transition: transform .2s, box-shadow .2s, border-color .2s;
}
.calc-card:hover { transform: translateY(-3px); box-shadow: var(--shadow); border-color: #c9d6e6; }
.calc-card i {
  font-style: normal; font-family: var(--font-mono); font-weight: 700; font-size: 16px;
  width: 44px; height: 44px; border-radius: 11px; display: grid; place-items: center;
  background: var(--copper-tint); color: var(--copper-deep);
}
.calc-card b { font-size: 16.5px; line-height: 1.3; }
.calc-card span { font-size: 14px; line-height: 1.5; color: var(--muted); flex: 1; }
.calc-card em { font-style: normal; font-weight: 700; color: var(--copper); font-size: 14px; }
.calc-trust { margin-top: 38px; padding: 22px 24px; border-radius: var(--radius); background: var(--mist); border: 1px solid var(--line); }
.calc-trust b { font-size: 16px; }
.calc-trust p { margin: 10px 0 0; font-size: 14.5px; line-height: 1.6; color: var(--ink-soft); }

@media (max-width: 1000px) {
  .calc { grid-template-columns: 1fr; }
  .calc-out { position: static; }
}
@media (max-width: 620px) {
  .calc-form { padding: 16px 16px 4px; }
  .calc-grid { grid-template-columns: 1fr; }
  .calc-out { padding: 16px; }
  .calc-row.is-key b { font-size: 18px; }
  .calc-row { flex-wrap: wrap; }
  .calc-row b { white-space: normal; }
  .calc-f { white-space: normal; }
  .calc-table { table-layout: fixed; }
  .calc-table td, .calc-table th { padding: 7px 6px; overflow-wrap: anywhere; }
  .calc-table td:last-child { white-space: normal; width: 42%; }
}
@media print {
  .calc-out { position: static; background: #fff; color: #000; box-shadow: none; border: 1px solid #999; }
  .calc-row span, .calc-row b, .calc-row b small, .calc-note, .calc-steps li { color: #000 !important; }
  .calc-actions { display: none; }
}
.calc-table.is-res td { background: var(--copper-tint); }
.calc-table.is-res td b { color: var(--copper-deep); }