/* TankDosing: calm aquatic greens and teals */
@font-face { font-family: "Inter"; src: url("/assets/fonts/inter-latin-wght-normal.woff2") format("woff2"); font-weight: 100 900; font-display: swap; }
@font-face { font-family: "Inter Tight"; src: url("/assets/fonts/inter-tight-latin-wght-normal.woff2") format("woff2"); font-weight: 100 900; font-display: swap; }
:root {
  --bg: #F3F7F5; --bg-2: #E8F0EC; --surface: #FFFFFF; --surface-2: #F8FBF9;
  --line: #D9E5DF; --line-strong: #C3D5CC;
  --ink: #102523; --ink-2: #334845; --muted: #5F726E;
  --teal: #0E6E66; --teal-600: #0B5C55; --teal-700: #094A45; --deep: #0B3B3A; --teal-50: #E2F3EE; --teal-100: #C6E8DE;
  --leaf: #2F8F6B; --aqua: #5FC4B0;
  --warn: #7A4B06; --warn-bg: #FFF5E3; --warn-line: #F0D9AE;
  --danger: #8E1F1F; --danger-bg: #FDECEC; --danger-line: #F2C3C3;
  --info-bg: #EAF5F2; --info-line: #C8E3DB;
  --radius: 14px; --radius-sm: 10px;
  --shadow: 0 1px 2px rgba(16,37,35,.04), 0 10px 30px -16px rgba(16,37,35,.18);
  --shadow-lg: 0 2px 4px rgba(16,37,35,.05), 0 24px 48px -24px rgba(11,59,58,.35);
  --font: "Inter", ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-display: "Inter Tight", "Inter", ui-sans-serif, system-ui, sans-serif;
}
[hidden] { display: none !important; }
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-padding-top: 80px; }
body { margin: 0; background: var(--bg); color: var(--ink); font-family: var(--font); font-size: 16px; line-height: 1.6; -webkit-font-smoothing: antialiased; }
img, svg { display: block; max-width: 100%; }
a { color: var(--teal); text-underline-offset: 3px; text-decoration-thickness: 1px; }
a:hover { color: var(--teal-700); }
h1, h2, h3 { font-family: var(--font-display); line-height: 1.12; letter-spacing: -0.02em; margin: 0 0 .5em; font-weight: 700; color: var(--ink); }
h1 { font-size: clamp(2rem, 4.4vw, 3.1rem); letter-spacing: -0.03em; }
h2 { font-size: clamp(1.4rem, 2.6vw, 1.9rem); }
h3 { font-size: 1.15rem; }
p { margin: 0 0 1em; }
.small { font-size: .875rem; } .muted { color: var(--muted); } .num { font-variant-numeric: tabular-nums; }
.sr-only { position: absolute !important; width: 1px; height: 1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; }
.container { max-width: 1180px; margin: 0 auto; padding: 0 20px; }
.narrow { max-width: 780px; }
:focus-visible { outline: 3px solid color-mix(in srgb, var(--teal) 55%, transparent); outline-offset: 2px; border-radius: 6px; }
.skip-link { position: absolute; left: 12px; top: -48px; background: var(--ink); color: #fff; padding: 8px 12px; border-radius: 8px; z-index: 100; }
.skip-link:focus { top: 12px; }
/* header */
.site-header { position: sticky; top: 0; z-index: 50; background: color-mix(in srgb, var(--bg) 86%, transparent); backdrop-filter: saturate(1.4) blur(10px); border-bottom: 1px solid var(--line); }
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand { display: inline-flex; align-items: center; gap: 10px; text-decoration: none; color: var(--ink); }
.brand-mark { width: 30px; height: 30px; }
.wordmark { font-family: var(--font-display); font-size: 1.28rem; letter-spacing: -0.03em; font-weight: 500; }
.wordmark b { font-weight: 750; color: var(--teal); }
.nav { display: flex; gap: 4px; }
.nav a { padding: 8px 12px; border-radius: 999px; color: var(--ink-2); text-decoration: none; font-weight: 550; font-size: .95rem; }
.nav a:hover { background: var(--bg-2); color: var(--ink); }
.nav a[aria-current="page"] { background: var(--teal-50); color: var(--teal-700); }
.nav-toggle { display: none; background: none; border: 1px solid var(--line); border-radius: 10px; width: 42px; height: 42px; padding: 8px; color: var(--ink); }
@media (max-width: 760px) {
  .nav-toggle { display: block; }
  .nav { display: none; position: absolute; left: 0; right: 0; top: 64px; flex-direction: column; background: var(--surface); border-bottom: 1px solid var(--line); padding: 10px 16px 16px; box-shadow: var(--shadow); }
  .nav.open { display: flex; }
  .nav a { padding: 12px; font-size: 1.05rem; }
}
/* hero */
.hero { padding: 40px 0 8px; background: radial-gradient(900px 380px at 100% 0, #DDF0E8 0, transparent 70%), radial-gradient(700px 300px at 0 0, #EEF7F3 0, transparent 70%); }
.eyebrow { display: inline-flex; gap: 8px; align-items: center; font-size: .8rem; letter-spacing: .12em; text-transform: uppercase; font-weight: 700; color: var(--teal); margin-bottom: 12px; }
.lede { font-size: 1.12rem; color: var(--ink-2); max-width: 720px; }
.pills { display: flex; flex-wrap: wrap; gap: 8px; margin: 14px 0 0; padding: 0; list-style: none; }
.pills li { background: var(--surface); border: 1px solid var(--line); border-radius: 999px; padding: 4px 12px; font-size: .85rem; color: var(--ink-2); }
/* cards and layout */
.section { padding: 32px 0; }
.card { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow); padding: 22px; }
.card + .card { margin-top: 16px; }
.card h2 { font-size: 1.25rem; }
.calc-grid { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.15fr); gap: 20px; align-items: start; }
@media (max-width: 920px) { .calc-grid { grid-template-columns: minmax(0, 1fr); } }
.results { position: sticky; top: 80px; }
@media (max-width: 920px) { .results { position: static; } }
.grid-2 { display: grid; grid-template-columns: minmax(0,1fr) minmax(0,1fr); gap: 12px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; }
@media (max-width: 520px) { .grid-3 { grid-template-columns: 1fr 1fr; } }
.tiles { display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: 16px; }
.tile { display: block; text-decoration: none; color: inherit; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px; box-shadow: var(--shadow); transition: transform .15s, box-shadow .15s; }
.tile:hover { transform: translateY(-2px); box-shadow: var(--shadow-lg); color: inherit; }
.tile h3 { color: var(--teal-700); margin-bottom: .3em; }
.tile p { color: var(--ink-2); font-size: .95rem; margin: 0; }
/* forms */
.field { display: flex; flex-direction: column; gap: 4px; margin-bottom: 12px; }
.field label, .legend { font-weight: 600; font-size: .9rem; color: var(--ink-2); }
.hint { font-size: .8rem; color: var(--muted); }
input[type="number"], input[type="text"], input[type="email"], select { font: inherit; font-size: 1rem; padding: 10px 12px; border: 1px solid var(--line-strong); border-radius: var(--radius-sm); background: var(--surface); color: var(--ink); width: 100%; min-height: 44px; }
input:focus, select:focus { border-color: var(--teal); outline: 3px solid var(--teal-100); }
.input-unit { display: flex; gap: 8px; } .input-unit input { flex: 1; } .input-unit select { width: auto; }
.check { display: flex; gap: 10px; align-items: flex-start; font-size: .92rem; margin: 6px 0; }
.check input { width: 18px; height: 18px; margin-top: 3px; accent-color: var(--teal); }
fieldset { border: 0; padding: 0; margin: 0 0 12px; }
.seg { display: inline-flex; background: var(--bg-2); border-radius: 999px; padding: 4px; gap: 4px; flex-wrap: wrap; }
.seg button { font: inherit; font-weight: 600; font-size: .9rem; border: 0; background: transparent; color: var(--ink-2); padding: 8px 14px; border-radius: 999px; cursor: pointer; min-height: 40px; }
.seg button[aria-pressed="true"] { background: var(--surface); color: var(--teal-700); box-shadow: 0 1px 3px rgba(0,0,0,.08); }
.mode-switch { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin-bottom: 16px; }
.mode-switch button { font: inherit; text-align: left; border: 2px solid var(--line); background: var(--surface); border-radius: var(--radius); padding: 12px 14px; cursor: pointer; color: var(--ink); }
.mode-switch button b { display: block; font-family: var(--font-display); font-size: 1.05rem; }
.mode-switch button span { font-size: .82rem; color: var(--muted); }
.mode-switch button[aria-pressed="true"] { border-color: var(--teal); background: var(--teal-50); }
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; font: inherit; font-weight: 650; padding: 10px 16px; border-radius: 999px; border: 1px solid transparent; cursor: pointer; text-decoration: none; min-height: 44px; }
.btn-primary { background: var(--teal); color: #fff; } .btn-primary:hover { background: var(--teal-700); color: #fff; }
.btn-ghost { background: var(--surface); border-color: var(--line-strong); color: var(--ink); } .btn-ghost:hover { background: var(--bg-2); color: var(--ink); }
.btn-row { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 12px; }
/* results */
.mode-banner { border-radius: var(--radius-sm); padding: 10px 14px; font-weight: 650; margin-bottom: 14px; display: flex; gap: 10px; align-items: center; }
.mode-banner.dry { background: #E7F4EC; color: #1B5E3E; border: 1px solid #C7E6D3; }
.mode-banner.stock { background: #E5F1F8; color: #154A6B; border: 1px solid #C5DEEE; }
table { width: 100%; border-collapse: collapse; font-size: .95rem; }
th, td { text-align: left; padding: 9px 8px; border-bottom: 1px solid var(--line); vertical-align: top; }
thead th { font-size: .78rem; letter-spacing: .06em; text-transform: uppercase; color: var(--muted); font-weight: 700; }
td.num, th.num { text-align: right; font-variant-numeric: tabular-nums; }
.big-dose { font-family: var(--font-display); font-weight: 750; font-size: 1.15rem; color: var(--deep); white-space: nowrap; }
.table-wrap { overflow-x: auto; }
.ppm-bars { display: grid; gap: 8px; }
.ppm-row { display: grid; grid-template-columns: 90px 1fr 120px; gap: 10px; align-items: center; font-size: .9rem; }
.bar { height: 10px; background: var(--bg-2); border-radius: 999px; position: relative; overflow: hidden; }
.bar i { position: absolute; inset: 0 auto 0 0; background: linear-gradient(90deg, var(--leaf), var(--aqua)); border-radius: 999px; }
.bar i.hot { background: linear-gradient(90deg, #D9822B, #C0392B); }
.bar .range { position: absolute; top: 0; bottom: 0; border-left: 2px solid rgba(11,59,58,.35); border-right: 2px solid rgba(11,59,58,.35); }
.alert { border-radius: var(--radius-sm); padding: 10px 14px; margin: 8px 0; font-size: .92rem; border: 1px solid; }
.alert.warn { background: var(--warn-bg); border-color: var(--warn-line); color: var(--warn); }
.alert.danger { background: var(--danger-bg); border-color: var(--danger-line); color: var(--danger); font-weight: 600; }
.alert.info { background: var(--info-bg); border-color: var(--info-line); color: var(--ink-2); }
.week { display: grid; grid-template-columns: repeat(7, 1fr); gap: 6px; }
.day { border: 1px solid var(--line); border-radius: 10px; padding: 8px 6px; text-align: center; font-size: .78rem; min-height: 86px; background: var(--surface-2); }
.day b { display: block; font-size: .85rem; margin-bottom: 4px; }
.tag { display: block; border-radius: 6px; padding: 2px 4px; margin-top: 3px; font-weight: 600; }
.tag.macro { background: #DDF1E6; color: #1B5E3E; } .tag.micro { background: #E3EEF9; color: #1E4B7A; } .tag.wc { background: #FFF0D9; color: #7A4B06; }
.recipe { background: var(--surface-2); border: 1px dashed var(--line-strong); border-radius: var(--radius-sm); padding: 14px; margin-top: 10px; }
.recipe h3 { margin-bottom: .4em; }
details.explainer { border: 1px solid var(--line); border-radius: var(--radius-sm); padding: 0 14px; background: var(--surface); margin: 8px 0; }
details.explainer summary { cursor: pointer; font-weight: 650; padding: 12px 0; }
.where-buy { border: 1px dashed var(--line-strong); border-radius: var(--radius-sm); padding: 12px 14px; color: var(--muted); font-size: .88rem; background: var(--surface-2); }
/* prose */
.prose { font-size: 1.04rem; } .prose h2 { margin-top: 1.6em; } .prose h3 { margin-top: 1.3em; }
.prose li { margin-bottom: .4em; } .prose table { margin: 1em 0; }
.callout { background: var(--teal-50); border-left: 4px solid var(--teal); padding: 14px 16px; border-radius: 0 10px 10px 0; margin: 1.2em 0; }
.sources { font-size: .9rem; } .sources li { word-break: break-word; }
.crumbs { font-size: .85rem; color: var(--muted); margin-bottom: 8px; } .crumbs a { color: var(--muted); }
.faq-item { border-top: 1px solid var(--line); padding: 14px 0; } .faq-item h3 { font-size: 1.05rem; }
/* pricing */
.plans { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; max-width: 880px; }
@media (max-width: 720px) { .plans { grid-template-columns: 1fr; } }
.plan { padding: 26px; } .plan.featured { border: 2px solid var(--teal); }
.price { font-family: var(--font-display); font-size: 2.4rem; font-weight: 750; letter-spacing: -0.03em; }
.price small { font-size: 1rem; color: var(--muted); font-weight: 500; }
.badge { display: inline-block; background: var(--teal-50); color: var(--teal-700); font-weight: 700; font-size: .75rem; letter-spacing: .08em; text-transform: uppercase; padding: 4px 10px; border-radius: 999px; }
.ticks { list-style: none; padding: 0; } .ticks li { padding-left: 26px; position: relative; margin: 8px 0; }
.ticks li::before { content: ""; position: absolute; left: 4px; top: 7px; width: 10px; height: 6px; border-left: 2px solid var(--leaf); border-bottom: 2px solid var(--leaf); transform: rotate(-45deg); }
.hp { position: absolute; left: -9999px; }
/* footer */
.site-footer { margin-top: 48px; background: var(--deep); color: #CFE3DD; padding: 40px 0 24px; }
.site-footer a { color: #E6F4EF; } .site-footer .wordmark { color: #fff; } .site-footer .wordmark b { color: var(--aqua); }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 24px; }
@media (max-width: 760px) { .footer-grid { grid-template-columns: 1fr 1fr; } }
.footer-grid ul { list-style: none; padding: 0; margin: 0; } .footer-grid li { margin: 6px 0; font-size: .92rem; }
.foot-h { color: #fff; font-size: .8rem; letter-spacing: .1em; text-transform: uppercase; }
.disclaimer { border-top: 1px solid rgba(255,255,255,.12); margin-top: 24px; padding-top: 16px; color: #A9C6BE; }
.tanks-list { display: grid; gap: 12px; }
.tank-row { display: flex; justify-content: space-between; align-items: center; gap: 12px; flex-wrap: wrap; }
/* print: only the weekly chart */
.print-only { display: none; }
@media print {
  body { background: #fff; } .site-header, .site-footer, .no-print, .skip-link { display: none !important; }
  .print-only { display: block; } .card { box-shadow: none; border: 1px solid #999; }
  .calc-grid { display: block; } .results { position: static; }
  .day { min-height: 110px; }
}

/* mobile overflow guard: grid children may shrink; segmented controls wrap */
.calc-grid > *, .grid-2 > *, .grid-3 > *, .card { min-width: 0; }
.seg { flex-wrap: wrap; }
.table-wrap, .out table { max-width: 100%; }
@media (max-width: 560px) {
  .week { grid-template-columns: repeat(4, minmax(0, 1fr)); }
  .day { padding: 6px 4px; }
  .day .tag { display: inline-block; max-width: 100%; overflow-wrap: anywhere; }
  table { font-size: .85rem; }
  th, td { padding-left: 4px; padding-right: 4px; overflow-wrap: anywhere; }
}