:root {
  --bg: #f6f7f5;
  --fg: #1a1c1a;
  --muted: #5d625d;
  --card: #ffffff;
  --line: #dfe2dd;
  --accent: #1f6f5c;
  --accent-soft: #e6f2ee;
  --accent-fg: #ffffff;
  --shadow: 0 1px 2px rgba(20, 30, 25, 0.06), 0 4px 16px rgba(20, 30, 25, 0.05);
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #131513;
    --fg: #ecefe9;
    --muted: #9ca39b;
    --card: #1c1f1c;
    --line: #313631;
    --accent: #5bc2a6;
    --accent-soft: #182a25;
    --accent-fg: #0d1512;
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.4), 0 4px 16px rgba(0, 0, 0, 0.25);
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 17px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
a { color: var(--accent); }
.wrap { max-width: 880px; margin: 0 auto; padding: 0 20px; }

header.site { background: var(--card); border-bottom: 1px solid var(--line); padding: 14px 0; }
header.site a {
  display: inline-flex; align-items: center; gap: 10px;
  color: var(--fg); font-weight: 700; font-size: 1.1rem; letter-spacing: -0.01em; text-decoration: none;
}
header.site a::before {
  content: ""; width: 14px; height: 14px; border-radius: 4px; background: var(--accent);
  box-shadow: 0 0 0 4px var(--accent-soft);
}

h1 { font-size: 2rem; line-height: 1.2; letter-spacing: -0.02em; margin: 36px 0 10px; }
h2 { font-size: 1.25rem; line-height: 1.3; margin: 40px 0 12px; }
.lead { color: var(--muted); font-size: 1.05rem; margin: 0 0 24px; max-width: 62ch; }

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 22px;
  box-shadow: var(--shadow);
}

/* калькулятор: поля слева, результат справа */
.calc { display: grid; gap: 16px; align-items: start; }
@media (min-width: 800px) {
  .calc { grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); }
  .calc #calc-result { position: sticky; top: 16px; }
}

.row { display: flex; flex-direction: column; gap: 6px; margin-bottom: 16px; }
.row:last-child { margin-bottom: 0; }
label { font-weight: 600; font-size: 0.92rem; }
input, select {
  font: inherit;
  min-height: 46px;
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--bg);
  color: var(--fg);
  width: 100%;
  transition: border-color 0.15s, box-shadow 0.15s;
}
select {
  appearance: none; -webkit-appearance: none; padding-right: 38px; cursor: pointer;
  background-image: linear-gradient(45deg, transparent 50%, var(--muted) 50%), linear-gradient(135deg, var(--muted) 50%, transparent 50%);
  background-position: calc(100% - 19px) 50%, calc(100% - 14px) 50%;
  background-size: 5px 5px, 5px 5px;
  background-repeat: no-repeat;
}
input:hover, select:hover { border-color: var(--muted); }
input:focus-visible, select:focus-visible {
  outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-soft), 0 0 0 4px var(--accent);
}

/* результат */
#calc-result { background: var(--accent-soft); border-color: transparent; min-height: 92px; }
#calc-result:empty::before { content: "…"; color: var(--muted); }
#calc-result p {
  display: flex; justify-content: space-between; align-items: baseline; gap: 16px;
  margin: 0; padding: 10px 0; border-bottom: 1px solid var(--line);
}
#calc-result p:first-child { padding-top: 0; }
#calc-result p:last-child { border-bottom: 0; padding-bottom: 0; }
#calc-result strong { flex: none; white-space: nowrap; text-align: right; font-size: 1.25rem; line-height: 1.3; color: var(--accent); font-variant-numeric: tabular-nums; }
#calc-result p:first-child strong { font-size: 1.6rem; }
#calc-result ul { margin: 6px 0 0; padding-left: 20px; }
.out-name { color: var(--muted); font-size: 0.95rem; }

.formula {
  background: var(--card); border: 1px solid var(--line); border-left: 4px solid var(--accent);
  border-radius: 10px; padding: 14px 16px; margin: 0 0 12px;
  font-family: ui-monospace, Menlo, Consolas, monospace; font-size: 0.93rem; line-height: 1.55;
}

details { background: var(--card); border: 1px solid var(--line); border-radius: 10px; padding: 0 16px; margin-bottom: 8px; }
summary {
  cursor: pointer; font-weight: 600; padding: 13px 0; list-style: none;
  display: flex; justify-content: space-between; gap: 12px; align-items: center;
}
summary::-webkit-details-marker { display: none; }
summary::after { content: "+"; color: var(--accent); font-size: 1.4rem; line-height: 1; flex: none; }
details[open] summary::after { content: "−"; }
details p { margin: 0 0 14px; color: var(--muted); }

.note { color: var(--muted); font-size: 0.88rem; margin-top: 36px; }

/* плитки: главная и «связанные» */
ul.tools {
  list-style: none; padding: 0; margin: 0;
  display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); gap: 12px;
}
ul.tools li { margin: 0; }
ul.tools a {
  display: block; height: 100%; padding: 14px 16px;
  background: var(--card); border: 1px solid var(--line); border-radius: 12px;
  color: var(--fg); font-weight: 600; font-size: 1rem; line-height: 1.35; text-decoration: none;
  transition: border-color 0.15s, box-shadow 0.15s, transform 0.15s;
}
ul.tools a:hover, ul.tools a:focus-visible {
  border-color: var(--accent); box-shadow: var(--shadow); transform: translateY(-1px); outline: none;
}
ul.tools a::after { content: "\00a0→"; color: var(--accent); }

footer.site { border-top: 1px solid var(--line); margin-top: 56px; padding: 22px 0 44px; color: var(--muted); font-size: 0.9rem; }
footer.site a { color: inherit; margin-left: 12px; }

@media (max-width: 480px) {
  body { font-size: 16px; }
  h1 { font-size: 1.55rem; margin-top: 26px; }
  .card { padding: 16px; }
  #calc-result p:first-child strong { font-size: 1.4rem; }
}

.consent { position: fixed; left: 0; right: 0; bottom: 0; z-index: 10; display: flex; flex-wrap: wrap; gap: 8px 12px; align-items: center; padding: 12px 16px; background: var(--card); border-top: 1px solid var(--line); font-size: 0.9rem; box-shadow: var(--shadow); }
.consent p { margin: 0; flex: 1 1 260px; }
.consent button { font: inherit; padding: 8px 16px; border: 1px solid var(--fg); background: var(--fg); color: var(--bg); border-radius: 8px; cursor: pointer; }
.consent button.secondary { background: transparent; color: var(--fg); }