.tons-page {
  --tons-ink: #26352d;
  --tons-muted: #5d6b62;
  --tons-line: #c9d1c8;
  --tons-paper: #faf9f5;
  --tons-green: #365f46;
  color: var(--tons-ink);
}

.tons-skip { position: absolute; left: 1rem; top: -5rem; z-index: 10; padding: .7rem 1rem; background: #fff; color: #173d27; }
.tons-skip:focus { top: 1rem; }
.tons-main { max-width: 1040px; }
.tons-crumb { margin: 1.35rem 0 .8rem; color: var(--tons-muted); font-size: .9rem; }
.tons-crumb a, .tons-section a, .tons-faq a { color: #24593a; text-underline-offset: .16em; }
.tons-tool { border-top: 4px solid var(--tons-green); background: var(--tons-paper); padding: clamp(1rem, 3vw, 2rem); }
.tons-heading { display: grid; grid-template-columns: minmax(0, 1fr) minmax(13rem, 18rem); gap: 1.5rem; align-items: end; }
.tons-eyebrow, .tons-result-kicker, .answer-note-label { margin: 0 0 .45rem; color: var(--tons-green); font-size: .74rem; font-weight: 750; letter-spacing: .1em; text-transform: uppercase; }
.tons-heading h1 { max-width: 17ch; margin: 0; font-size: clamp(1.8rem, 4vw, 2.8rem); line-height: 1.08; letter-spacing: -.035em; }
.tons-lead { max-width: 66ch; margin: .85rem 0 0; color: #43534a; font-size: 1.02rem; line-height: 1.55; }
.tons-answer-note { display: grid; gap: .45rem; border-left: 1px solid #aebdaf; padding: .2rem 0 .2rem 1rem; color: var(--tons-muted); font-size: .9rem; }
.tons-answer-note strong { color: var(--tons-ink); font-size: 1.05rem; }
.tons-workspace { display: grid; grid-template-columns: minmax(0, 1fr) minmax(17rem, .8fr); gap: 1rem; margin-top: 1.45rem; align-items: start; }
.tons-form { display: grid; gap: .9rem; min-width: 0; }
.tons-direction { display: flex; flex-wrap: wrap; gap: .55rem 1rem; min-width: 0; margin: 0; border: 1px solid var(--tons-line); padding: .8rem; }
.tons-direction legend { padding: 0 .35rem; font-weight: 700; }
.tons-direction label { display: inline-flex; align-items: center; gap: .45rem; min-height: 2.6rem; padding: .4rem .6rem; border: 1px solid transparent; cursor: pointer; }
.tons-direction label:has(input:checked) { border-color: #9eae9f; background: #edf1e9; }
.tons-direction input { accent-color: var(--tons-green); }
.tons-field { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: .4rem .7rem; align-items: center; font-weight: 700; }
.tons-field input, .tons-field select { grid-column: 1 / -1; width: 100%; min-height: 2.9rem; border: 1px solid #9aa99c; border-radius: 2px; background: #fff; color: var(--tons-ink); padding: .68rem .75rem; font: inherit; font-weight: 450; }
.tons-field input:focus, .tons-field select:focus, .tons-button-secondary:focus-visible, .tons-copy:focus-visible, .tons-text-button:focus-visible { outline: 3px solid #b6d78c; outline-offset: 2px; }
.tons-unit { color: var(--tons-muted); font-size: .78rem; font-weight: 600; }
.tons-field small { grid-column: 1 / -1; color: var(--tons-muted); font-size: .82rem; font-weight: 450; line-height: 1.4; }
.tons-form-actions { display: flex; flex-wrap: wrap; gap: .65rem; align-items: center; }
.tons-button-secondary, .tons-copy { min-height: 2.8rem; border: 1px solid var(--tons-green); border-radius: 2px; background: var(--tons-green); color: #fff; padding: .55rem .9rem; font: inherit; font-size: .91rem; font-weight: 700; cursor: pointer; }
.tons-button-secondary:hover, .tons-copy:not(:disabled):hover { background: #244b34; }
.tons-text-button { min-height: 2.8rem; border: 0; background: transparent; color: #2d563b; padding: .55rem .7rem; font: inherit; text-decoration: underline; text-underline-offset: .15em; cursor: pointer; }
.tons-example-disclaimer { margin: -.25rem 0 0; color: var(--tons-muted); font-size: .78rem; }
.tons-result { border: 1px solid #b6c3b5; border-top: 4px solid var(--tons-green); background: #eef1e9; padding: 1rem; min-width: 0; }
.tons-result h2 { margin: 0; font-size: 1.25rem; line-height: 1.2; }
.tons-answer { margin: .85rem 0 .35rem; color: #214c32; font-size: clamp(1.65rem, 4vw, 2.25rem); font-weight: 760; line-height: 1.1; overflow-wrap: anywhere; }
.tons-detail { margin: .25rem 0; color: #425249; font-size: .9rem; }
.tons-density-readout { margin: .8rem 0; border-top: 1px solid #c5cec2; border-bottom: 1px solid #c5cec2; padding: .6rem 0; }
.tons-density-readout div { display: flex; justify-content: space-between; gap: .7rem; }
.tons-density-readout dt { color: var(--tons-muted); }
.tons-density-readout dd { margin: 0; font-weight: 700; text-align: right; }
.tons-calculation { padding: .65rem; background: #fff; color: #39483f; font-size: .84rem; line-height: 1.5; overflow-wrap: anywhere; }
.tons-status, .tons-copy-status { min-height: 1.4em; margin: .45rem 0; color: #43534a; font-size: .84rem; }
.tons-copy:disabled { border-color: #a5aea5; background: #c5cbc5; color: #455047; cursor: not-allowed; }
.tons-copy { min-height: 2.55rem; }
.tons-result-boundary { margin: .9rem 0 0; border-top: 1px solid #c5cec2; padding-top: .7rem; color: #46534a; font-size: .78rem; line-height: 1.45; }
.tons-figure { margin: 1.25rem 0 2rem; }
.tons-figure img { display: block; width: 100%; height: auto; border: 1px solid var(--tons-line); background: #fbfaf6; }
.tons-figure figcaption { margin-top: .45rem; color: var(--tons-muted); font-size: .82rem; }
.tons-section { max-width: 76ch; margin: 2rem auto; color: #36453c; line-height: 1.65; }
.tons-section h2 { margin: 0 0 .65rem; color: var(--tons-ink); font-size: 1.35rem; line-height: 1.25; }
.tons-section p { margin: .7rem 0; }
.tons-formula { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: .65rem; margin: 1rem 0; }
.tons-formula p { margin: 0; border-left: 2px solid #75917b; background: #f3f3ed; padding: .75rem; font-size: .9rem; }
.tons-unit-ledger { border-top: 1px solid var(--tons-line); }
.tons-unit-ledger div { display: grid; grid-template-columns: minmax(8rem, .6fr) 1fr; gap: .9rem; border-bottom: 1px solid var(--tons-line); padding: .65rem .15rem; }
.tons-unit-ledger strong { color: #284b34; font-variant-numeric: tabular-nums; }
.tons-faq details { border-bottom: 1px solid var(--tons-line); padding: .75rem .15rem; }
.tons-faq summary { color: var(--tons-ink); font-weight: 700; cursor: pointer; }
.tons-faq details p { margin-bottom: .1rem; }
.tons-next { padding: 1rem; border-left: 3px solid #77907b; background: #f2f2eb; }
.tons-next h2 { margin-bottom: .35rem; }

@media (max-width: 720px) {
  .tons-heading { grid-template-columns: 1fr; gap: .9rem; }
  .tons-heading h1 { max-width: none; }
  .tons-answer-note { max-width: none; }
  .tons-workspace { grid-template-columns: 1fr; }
  .tons-formula { grid-template-columns: 1fr; }
}

@media (max-width: 390px) {
  .tons-main { padding-inline: .75rem; }
  .tons-tool { padding: .9rem; }
  .tons-direction { gap: .25rem; padding: .65rem; }
  .tons-direction label { padding-inline: .35rem; font-size: .9rem; }
  .tons-unit-ledger div { grid-template-columns: 1fr; gap: .15rem; }
  .tons-form-actions { align-items: stretch; }
  .tons-button-secondary { flex: 1 1 11rem; }
}