/* String Tension Lab
   Layout: a string-pack label on top (series, gauges, condensed headline), a spec strip, then the
   strings themselves drawn as a chart; everything else is ruled tables. Steel neutrals, phosphor-bronze
   accent. Archivo (condensed) for headlines, labels and numbers; Atkinson Hyperlegible Next for text. */

@font-face{font-family:'Archivo';font-style:normal;font-weight:500 800;font-stretch:62% 100%;font-display:swap;src:url(/static/fonts/archivo-normal-latin-ext.woff2) format('woff2');unicode-range:U+0100-02BA,U+02BD-02C5,U+02C7-02CC,U+02CE-02D7,U+02DD-02FF,U+0304,U+0308,U+0329,U+1D00-1DBF,U+1E00-1E9F,U+1EF2-1EFF,U+2020,U+20A0-20AB,U+20AD-20C4,U+2113,U+2C60-2C7F,U+A720-A7FF;}
@font-face{font-family:'Archivo';font-style:normal;font-weight:500 800;font-stretch:62% 100%;font-display:swap;src:url(/static/fonts/archivo-normal-latin.woff2) format('woff2');unicode-range:U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD;}
@font-face{font-family:'Atkinson Hyperlegible Next';font-style:normal;font-weight:400 600;font-display:swap;src:url(/static/fonts/atkinson-hyperlegible-next-normal-latin-ext.woff2) format('woff2');unicode-range:U+0100-02BA,U+02BD-02C5,U+02C7-02CC,U+02CE-02D7,U+02DD-02FF,U+0304,U+0308,U+0329,U+1D00-1DBF,U+1E00-1E9F,U+1EF2-1EFF,U+2020,U+20A0-20AB,U+20AD-20C4,U+2113,U+2C60-2C7F,U+A720-A7FF;}
@font-face{font-family:'Atkinson Hyperlegible Next';font-style:normal;font-weight:400 600;font-display:swap;src:url(/static/fonts/atkinson-hyperlegible-next-normal-latin.woff2) format('woff2');unicode-range:U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD;}
@font-face{font-family:'Atkinson Hyperlegible Next';font-style:italic;font-weight:400;font-display:swap;src:url(/static/fonts/atkinson-hyperlegible-next-italic-latin-ext.woff2) format('woff2');unicode-range:U+0100-02BA,U+02BD-02C5,U+02C7-02CC,U+02CE-02D7,U+02DD-02FF,U+0304,U+0308,U+0329,U+1D00-1DBF,U+1E00-1E9F,U+1EF2-1EFF,U+2020,U+20A0-20AB,U+20AD-20C4,U+2113,U+2C60-2C7F,U+A720-A7FF;}
@font-face{font-family:'Atkinson Hyperlegible Next';font-style:italic;font-weight:400;font-display:swap;src:url(/static/fonts/atkinson-hyperlegible-next-italic-latin.woff2) format('woff2');unicode-range:U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD;}

:root {
  color-scheme: light;
  --ground: #eceeee;        /* brushed steel, faint cool bias */
  --sheet: #f8f9f8;
  --ink: #16191b;
  --ink-2: #454c51;
  --ink-3: #6a7277;
  --rule: #cfd4d6;
  --rule-soft: #e1e4e5;
  --string: #3e474e;        /* nickel/steel string */
  --winding: rgba(248, 249, 248, .55);
  --bronze: #87561a;        /* phosphor bronze: links, target line */
  --bronze-soft: #f1e6d6;
  --focus: #1d5fa8;
  --font-display: "Archivo", "Arial Narrow", "Helvetica Neue", Arial, sans-serif;
  --font-text: "Atkinson Hyperlegible Next", "Segoe UI", system-ui, sans-serif;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    color-scheme: dark;
    --ground: #101213; --sheet: #171a1c; --ink: #eceeee; --ink-2: #bcc3c7; --ink-3: #8b9499;
    --rule: #33393d; --rule-soft: #24292c; --string: #c9d0d4; --winding: rgba(23, 26, 28, .5);
    --bronze: #dba760; --bronze-soft: #2c2318; --focus: #7db3f0;
  }
}
:root[data-theme="dark"] {
  color-scheme: dark;
  --ground: #101213; --sheet: #171a1c; --ink: #eceeee; --ink-2: #bcc3c7; --ink-3: #8b9499;
  --rule: #33393d; --rule-soft: #24292c; --string: #c9d0d4; --winding: rgba(23, 26, 28, .5);
  --bronze: #dba760; --bronze-soft: #2c2318; --focus: #7db3f0;
}

/* unit switch: every value exists in lb, kg and N; show one */
:root[data-units="lb"] .u:not(.u-lb),
:root[data-units="kg"] .u:not(.u-kg),
:root[data-units="n"] .u:not(.u-n) { display: none; }

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0; background: var(--ground); color: var(--ink);
  font: 400 17px/1.55 var(--font-text);
}
a { color: var(--bronze); text-decoration-thickness: 1px; text-underline-offset: 3px; }
a:hover { text-decoration-thickness: 2px; }
:focus-visible { outline: 2px solid var(--focus); outline-offset: 2px; }
.muted { color: var(--ink-3); }

.masthead { background: var(--sheet); border-bottom: 1px solid var(--rule); }
.masthead-inner, .page, .colophon {
  max-width: 980px; margin: 0 auto;
  padding-left: max(16px, env(safe-area-inset-left, 0px)); padding-right: max(16px, env(safe-area-inset-right, 0px));
}
.masthead-inner { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 10px 20px; padding-block: 10px; }
.wordmark { display: inline-flex; align-items: center; gap: 10px; color: var(--ink); text-decoration: none;
  font: 700 15px/1 var(--font-display); font-stretch: 75%; text-transform: uppercase; letter-spacing: .08em; }
.glyph { width: 28px; height: 22px; fill: none; stroke: var(--ink); stroke-linecap: round; }
.glyph path { stroke-width: 1.2; }
.glyph .w { stroke-width: 2.4; }
.controls { display: flex; flex-wrap: wrap; gap: 8px; }
.seg { display: inline-flex; border: 1px solid var(--rule); border-radius: 3px; overflow: hidden; }
.seg button, .seg a {
  font: 600 12px/1 var(--font-display); font-stretch: 85%; letter-spacing: .04em; text-transform: uppercase;
  padding: 7px 10px; border: 0; background: transparent; color: var(--ink-2); cursor: pointer; text-decoration: none;
}
.seg > * + * { border-left: 1px solid var(--rule); }
.seg [aria-pressed="true"], .seg [aria-current="true"] { background: var(--ink); color: var(--sheet); }

.page { padding-block: 20px 8px; }
.crumbs { font-size: 14px; color: var(--ink-3); }
.crumbs a { color: var(--ink-2); }

.lead { margin: 18px 0 8px; }
.pack { margin: 0 0 6px; font: 600 13px/1.3 var(--font-display); font-stretch: 80%; text-transform: uppercase;
  letter-spacing: .1em; color: var(--ink-3); }
.pack-gauges { color: var(--bronze); }
h1, h2, h3 { font-family: var(--font-display); text-wrap: balance; }
h1 { font-size: clamp(1.7rem, 4.4vw, 2.6rem); line-height: 1.05; font-weight: 750; font-stretch: 72%; margin: 0 0 14px; letter-spacing: -.005em; }
h2 { font-size: 1.35rem; line-height: 1.15; font-weight: 700; font-stretch: 80%; margin: 2.2em 0 .7em; padding-top: .7em; border-top: 2px solid var(--ink); }
h3 { font-size: 1.05rem; font-weight: 700; font-stretch: 85%; margin: 1.2em 0 .4em; }
.lede { max-width: 66ch; color: var(--ink-2); margin: 0; }
.lede strong { color: var(--ink); font-weight: 600; }

/* spec strip: four facts, separated by rules, no cards */
.spec { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); margin: 22px 0 0; border-top: 1px solid var(--rule); border-bottom: 1px solid var(--rule); }
.spec > div { padding: 12px 14px 12px 0; min-width: 0; }
.spec > div:nth-child(even) { padding-left: 14px; border-left: 1px solid var(--rule); }
.spec > div:nth-child(n+3) { border-top: 1px solid var(--rule); }
@media (min-width: 760px) {
  .spec { grid-template-columns: repeat(4, minmax(0, 1fr)); }
  .spec > div { padding-left: 14px; border-left: 1px solid var(--rule); }
  .spec > div:first-child { padding-left: 0; border-left: 0; }
  .spec > div:nth-child(n+3) { border-top: 0; }
}
.spec dt { font: 600 12px/1.2 var(--font-display); font-stretch: 85%; text-transform: uppercase; letter-spacing: .08em; color: var(--ink-3); }
.spec dd { margin: 0; }
.spec .big { font: 700 1.55rem/1.2 var(--font-display); font-stretch: 80%; font-variant-numeric: tabular-nums; margin-top: 4px; }
.spec .sub { font-size: 14px; color: var(--ink-2); }

/* chart */
.chart-wrap { margin: 0 0 18px; }
.chart { width: 100%; height: auto; display: block; overflow: visible; }
.chart text { font-family: var(--font-display); }
.chart .grid { stroke: var(--rule-soft); stroke-width: 1; }
.chart .baseline { stroke: var(--ink-3); stroke-width: 1; }
.chart .tick { fill: var(--ink-3); font-size: 12px; font-variant-numeric: tabular-nums; }
.chart .axis-title { fill: var(--ink-3); font-size: 12px; }
.chart .row-label { fill: var(--ink-2); font-size: 14px; font-weight: 600; font-variant-numeric: tabular-nums; }
.chart .row-label .pos { fill: var(--ink-3); }
.chart .row-label .gauge { fill: var(--ink-3); font-weight: 500; }
.chart .string { stroke: var(--string); stroke-linecap: round; }
.chart .winding { stroke: url(#wind); stroke-linecap: round; }
.chart .wind { fill: var(--winding); }
.chart .value { fill: var(--ink); font-size: 13px; font-weight: 600; font-variant-numeric: tabular-nums;
  stroke: var(--ground); stroke-width: 4px; stroke-linejoin: round; paint-order: stroke; }
.chart .row:hover .value, .chart .row.is-active .value, .chart .row:focus-visible .value { stroke: var(--bronze-soft); }
.chart .hit { fill: transparent; }
.chart .row { cursor: pointer; outline: none; }
.chart .row:hover .hit, .chart .row.is-active .hit, .chart .row:focus-visible .hit { fill: var(--bronze-soft); }
.chart .row:focus-visible .row-label { fill: var(--focus); }
.chart .ref { stroke-width: 1.5; stroke-dasharray: 4 4; }
.chart .ref.avg { stroke: var(--ink-3); }
.chart .ref.target { stroke: var(--bronze); }
.chart .ref-label { font-size: 12px; font-weight: 600; }
.chart .ref-label.avg { fill: var(--ink-2); }
.chart .ref-label.target { fill: var(--bronze); }
.chart-wrap figcaption { font-size: 14px; color: var(--ink-3); margin-top: 6px; display: grid; gap: 4px; }
.chart-wrap figcaption .target-key { color: var(--ink-2); }
.chart-wrap figcaption .target-key::before { content: ""; display: inline-block; width: 18px; margin-right: 6px; vertical-align: middle;
  border-top: 2px dashed var(--bronze); }

.tooltip { position: absolute; z-index: 20; pointer-events: none; display: flex; flex-direction: column; gap: 2px;
  background: var(--ink); color: var(--sheet); padding: 8px 11px; border-radius: 3px; font-size: 13px; max-width: 260px;
  box-shadow: 0 6px 18px rgba(0, 0, 0, .18); }
.tooltip strong { font: 600 12px/1.2 var(--font-display); letter-spacing: .06em; text-transform: uppercase; }
.tooltip .tt-value { font: 700 1.25rem/1.15 var(--font-display); font-stretch: 85%; font-variant-numeric: tabular-nums; }
.tooltip .tt-meta { opacity: .8; }

/* tables: ruled, no boxes */
.table-wrap { overflow-x: auto; -webkit-overflow-scrolling: touch; }
table.data { border-collapse: collapse; width: 100%; font-size: 15px; font-variant-numeric: tabular-nums; }
.data th, .data td { padding: 8px 12px 8px 0; border-bottom: 1px solid var(--rule-soft); text-align: left; white-space: nowrap; }
.data th { font: 600 12px/1.2 var(--font-display); font-stretch: 85%; letter-spacing: .07em; text-transform: uppercase;
  color: var(--ink-3); border-bottom: 1px solid var(--ink); }
.data .num { text-align: right; }
.data td:last-child, .data th:last-child { padding-right: 0; }
.data .gauge, .gauge { font-family: var(--font-display); font-weight: 600; font-stretch: 85%; }
.data tr.hl td { background: var(--bronze-soft); }
.data tfoot td { font-weight: 600; border-bottom: 0; border-top: 1px solid var(--ink); }

.rec { padding-left: 1.4em; margin: 0; }
.rec li { margin: .5em 0; }
.rec-name { font-weight: 600; }
.rec .gauge { margin: 0 .4em; color: var(--ink-2); }
.rec-meta { color: var(--ink-2); }
.custom { margin-top: 18px; padding: 2px 0 6px 16px; border-left: 3px solid var(--bronze); }
.custom-list { list-style: none; padding: 0; margin: 8px 0; display: grid; gap: 4px; }
.custom-list .note-name { display: inline-block; min-width: 2.6em; font-weight: 600; }
.note { color: var(--ink-3); font-size: 14px; }
.about { color: var(--ink-2); max-width: 70ch; }
.sources { padding-left: 1.2em; font-size: 15px; }

.hub h2 { font-size: 1.1rem; margin: 1.6em 0 .4em; padding-top: .5em; border-top-width: 1px; }
.hub h2 .muted { font: 400 15px var(--font-text); }
.links { list-style: none; padding: 0; margin: 0; display: flex; flex-wrap: wrap; gap: 6px 18px; font-size: 15px; }

.colophon { color: var(--ink-3); font-size: 14px; padding-block: 28px 36px; border-top: 1px solid var(--rule); margin-top: 40px; }
@media (max-width: 520px) {
  body { font-size: 16px; }
  .seg button, .seg a { padding: 7px 8px; }
}
@media (prefers-reduced-motion: reduce) { * { transition: none !important; } }

/* navigation + buttons */
.navlink { font: 600 13px/1 var(--font-display); font-stretch: 85%; letter-spacing: .06em; text-transform: uppercase;
  color: var(--ink); text-decoration: none; margin-right: auto; padding: 7px 0; border-bottom: 2px solid var(--bronze); }
.btn { display: inline-block; font: 600 13px/1 var(--font-display); font-stretch: 85%; letter-spacing: .05em; text-transform: uppercase;
  padding: 10px 14px; border: 1px solid var(--ink); border-radius: 3px; background: var(--sheet); color: var(--ink);
  text-decoration: none; cursor: pointer; }
.btn:hover { background: var(--ink); color: var(--sheet); }
.linklike { font: inherit; font-weight: 600; color: var(--bronze); background: none; border: 0; padding: 0; cursor: pointer;
  text-decoration: underline; text-decoration-thickness: 1px; text-underline-offset: 3px; }

/* calculator */
.calc-controls { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 230px), 1fr)); gap: 16px 20px;
  padding: 18px 0; border-top: 2px solid var(--ink); border-bottom: 1px solid var(--rule); margin-top: 18px; }
.calc-controls .wide { grid-column: 1 / -1; }
.field { display: flex; flex-direction: column; gap: 6px; min-width: 0; }
.field .label { font: 600 12px/1.2 var(--font-display); font-stretch: 85%; letter-spacing: .08em; text-transform: uppercase; color: var(--ink-3); }
.calc select, .calc input[type="number"] {
  font: 400 16px/1.3 var(--font-text); color: var(--ink); background: var(--sheet); border: 1px solid var(--rule);
  border-radius: 3px; padding: 8px 10px; width: 100%; min-width: 0; }
.calc input[type="number"] { font-variant-numeric: tabular-nums; }
.calc .seg { flex-wrap: wrap; width: fit-content; max-width: 100%; }
.calc .seg button { font-size: 13px; padding: 9px 12px; }
.custom-scale { display: grid; gap: 8px; margin-top: 8px; font-size: 15px; }
.custom-scale label, .field .inline { display: grid; gap: 4px; font-size: 14px; color: var(--ink-2); }
.custom-scale .check { display: flex; align-items: center; gap: 8px; }
.field .inline { margin-top: 8px; }
.calc-share { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; padding: 14px 0 4px; }
.calc-results .lede { margin-top: 14px; }
.warn { border-left: 3px solid var(--bronze); padding: 4px 0 4px 12px; color: var(--ink); }
.data.edit select { width: auto; padding: 5px 8px; font-size: 15px; }
.data.edit td { vertical-align: middle; }
.chart .ref.goal { stroke: var(--ink); stroke-dasharray: 2 3; }
.chart .ref-label.goal { fill: var(--ink); }

/* personal feel */
.chart .ref.mine { stroke: var(--focus); stroke-width: 2; stroke-dasharray: 1 3; stroke-linecap: round; }
.chart .ref-label.mine { fill: var(--focus); }
.spec .mine { color: var(--focus); font-weight: 600; }
.spec .mine-setup a { font-size: 14px; }
.mypref { grid-column: 1 / -1; display: grid; gap: 8px; padding: 12px 14px; border-left: 3px solid var(--focus); background: var(--sheet); }
.mypref .actions { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }
.mypref p { margin: 0; }