/* switchcurves — design system */

@font-face { font-family: "Plex Sans"; src: url("/static/fonts/ibm-plex-sans-400.woff2") format("woff2"); font-weight: 400; font-display: swap; }
@font-face { font-family: "Plex Sans"; src: url("/static/fonts/ibm-plex-sans-500.woff2") format("woff2"); font-weight: 500; font-display: swap; }
@font-face { font-family: "Plex Sans"; src: url("/static/fonts/ibm-plex-sans-600.woff2") format("woff2"); font-weight: 600; font-display: swap; }
@font-face { font-family: "Plex Mono"; src: url("/static/fonts/ibm-plex-mono-400.woff2") format("woff2"); font-weight: 400; font-display: swap; }
@font-face { font-family: "Plex Mono"; src: url("/static/fonts/ibm-plex-mono-500.woff2") format("woff2"); font-weight: 500; font-display: swap; }

:root {
  --paper: #f7f6f2;
  --paper-2: #efede6;
  --card: #ffffff;
  --ink: #16202b;
  --ink-2: #47515e;
  --muted: #8a929d;
  --line: #e2e0d8;
  --grid-minor: rgba(22, 32, 43, 0.045);
  --grid-major: rgba(22, 32, 43, 0.085);
  --accent: #e4572e;
  --accent-soft: rgba(228, 87, 46, 0.1);
  --linear: #2f6fdf;
  --tactile: #d08a17;
  --clicky: #d6453d;
  --release: #6b7785;
  --radius: 14px;
  --radius-sm: 8px;
  --shadow: 0 1px 2px rgba(22, 32, 43, 0.04), 0 8px 24px -12px rgba(22, 32, 43, 0.12);
  --shadow-lift: 0 2px 4px rgba(22, 32, 43, 0.05), 0 18px 40px -16px rgba(22, 32, 43, 0.22);
  --sans: "Plex Sans", system-ui, -apple-system, "Segoe UI", sans-serif;
  --mono: "Plex Mono", ui-monospace, "SF Mono", Menlo, monospace;
  --max: 1120px;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root {
    --paper: #0e1620;
    --paper-2: #131d29;
    --card: #15202c;
    --ink: #e8edf3;
    --ink-2: #aab5c2;
    --muted: #6f7c8b;
    --line: #233142;
    --grid-minor: rgba(140, 180, 230, 0.05);
    --grid-major: rgba(140, 180, 230, 0.09);
    --accent: #ff7a4d;
    --accent-soft: rgba(255, 122, 77, 0.12);
    --linear: #6aa0ff;
    --tactile: #f0b443;
    --clicky: #ff6b61;
    --release: #8e9bab;
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.3), 0 8px 24px -12px rgba(0, 0, 0, 0.5);
    --shadow-lift: 0 2px 4px rgba(0, 0, 0, 0.3), 0 18px 40px -16px rgba(0, 0, 0, 0.6);
    color-scheme: dark;
  }
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--sans);
  font-size: 16.5px;
  line-height: 1.6;
  color: var(--ink);
  background-color: var(--paper);
  background-image:
    linear-gradient(var(--grid-major) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-major) 1px, transparent 1px),
    linear-gradient(var(--grid-minor) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-minor) 1px, transparent 1px);
  background-size: 120px 120px, 120px 120px, 24px 24px, 24px 24px;
  background-position: -1px -1px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration-color: color-mix(in srgb, currentColor 35%, transparent); text-underline-offset: 3px; transition: color .15s, text-decoration-color .15s; }
a:hover { color: var(--accent); text-decoration-color: var(--accent); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 4px; }
::selection { background: var(--accent-soft); }

.wrap { max-width: var(--max); margin: 0 auto; padding: 0 24px; }
.mono { font-family: var(--mono); }
.muted { color: var(--muted); }
.eyebrow { font-family: var(--mono); font-size: 12px; letter-spacing: .12em; text-transform: uppercase; color: var(--accent); margin: 0 0 12px; }

h1, h2, h3 { line-height: 1.15; letter-spacing: -0.02em; margin: 0 0 .5em; font-weight: 600; }
h1 { font-size: clamp(34px, 5vw, 54px); letter-spacing: -0.035em; text-wrap: balance; }
h2 { font-size: clamp(24px, 3vw, 30px); }
h3 { font-size: 19px; letter-spacing: -0.01em; }
p { margin: 0 0 1em; }
.lead { font-size: 19px; color: var(--ink-2); max-width: 62ch; }

/* Header */
.site-header {
  position: sticky; top: 0; z-index: 20;
  backdrop-filter: saturate(1.4) blur(14px);
  -webkit-backdrop-filter: saturate(1.4) blur(14px);
  background: color-mix(in srgb, var(--paper) 78%, transparent);
  border-bottom: 1px solid var(--line);
}
.site-header .wrap { display: flex; align-items: center; gap: 28px; height: 64px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 600; letter-spacing: -0.02em; text-decoration: none; font-size: 18px; }
.brand:hover { color: var(--ink); }
.brand svg { width: 30px; height: 30px; }
.brand .dot { color: var(--accent); }
.nav { display: flex; gap: 4px; margin-left: auto; align-items: center; }
.nav a { text-decoration: none; font-size: 15px; color: var(--ink-2); padding: 7px 12px; border-radius: 999px; transition: background .15s, color .15s; }
.nav a:hover { color: var(--ink); background: var(--paper-2); }
.nav a[aria-current="page"] { color: var(--ink); background: var(--paper-2); }
.nav .btn { margin-left: 8px; color: var(--paper); }
.nav .btn:hover { color: var(--paper); background: var(--ink); }
.nav-toggle { display: none; }

/* Buttons */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  font: 500 15px/1 var(--sans); text-decoration: none; cursor: pointer;
  padding: 11px 18px; border-radius: 999px; border: 1px solid var(--ink);
  background: var(--ink); color: var(--paper);
  transition: transform .15s, box-shadow .15s, background .15s, color .15s;
}
.btn:hover { color: var(--paper); transform: translateY(-1px); box-shadow: var(--shadow-lift); }
.btn:active { transform: translateY(0); }
.btn.ghost { background: transparent; color: var(--ink); border-color: var(--line); }
.btn.ghost:hover { color: var(--ink); border-color: var(--ink-2); }
.btn.small { padding: 8px 14px; font-size: 14px; }
.btn[disabled] { opacity: .6; cursor: progress; transform: none; box-shadow: none; }

/* Cards */
.card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow); }
.card.pad { padding: 28px; }
a.card { display: block; text-decoration: none; transition: transform .2s ease, box-shadow .2s ease, border-color .2s; }
a.card:hover { color: inherit; transform: translateY(-3px); box-shadow: var(--shadow-lift); border-color: color-mix(in srgb, var(--accent) 35%, var(--line)); }

/* Type pills */
.pill { display: inline-flex; align-items: center; gap: 6px; font: 500 12px/1 var(--mono); letter-spacing: .06em; text-transform: uppercase; padding: 6px 10px; border-radius: 999px; background: var(--paper-2); color: var(--ink-2); }
.pill::before { content: ""; width: 7px; height: 7px; border-radius: 50%; background: currentColor; }
.pill.linear { color: var(--linear); background: color-mix(in srgb, var(--linear) 11%, transparent); }
.pill.tactile { color: var(--tactile); background: color-mix(in srgb, var(--tactile) 13%, transparent); }
.pill.clicky { color: var(--clicky); background: color-mix(in srgb, var(--clicky) 11%, transparent); }

/* Sections */
main { padding-bottom: 96px; }
section { margin-top: 72px; }
.section-head { display: flex; align-items: end; justify-content: space-between; gap: 24px; margin-bottom: 24px; }
.section-head p { margin: 0; color: var(--ink-2); }

/* Hero */
.hero { padding-top: 72px; display: grid; grid-template-columns: 1fr 1.15fr; gap: 48px; align-items: center; }
.hero h1 .accent { color: var(--accent); }
.hero-actions { display: flex; gap: 12px; margin-top: 28px; flex-wrap: wrap; }
.hero-chart { padding: 20px 20px 12px; }
.hero-chart .legend { margin: 6px 6px 4px; }
.stats { display: flex; gap: 36px; margin-top: 36px; }
.stats div { font-family: var(--mono); font-size: 13px; color: var(--muted); }
.stats strong { display: block; font: 600 26px/1.1 var(--sans); color: var(--ink); letter-spacing: -0.02em; }

/* Switch grid */
.grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: 18px; }
.switch-card { padding: 20px; }
.switch-card .top { display: flex; align-items: center; gap: 14px; margin-bottom: 14px; }
.switch-card .icon { width: 44px; height: 44px; flex: none; }
.switch-card h3 { margin: 0; font-size: 17px; }
.switch-card .brand-name { font-size: 13px; color: var(--muted); font-family: var(--mono); }
.switch-card .spark { height: 64px; width: 100%; margin: 4px 0 12px; }
.switch-card .meta { display: flex; justify-content: space-between; align-items: center; font: 13px var(--mono); color: var(--ink-2); }

/* Charts */
.chart { width: 100%; height: auto; overflow: visible; }
.chart .grid-minor { stroke: var(--grid-minor); stroke-width: 1; }
.chart .grid-major { stroke: var(--grid-major); stroke-width: 1; }
.chart .axis { stroke: var(--ink-2); stroke-width: 1.2; }
.chart .tick { font: 11px var(--mono); fill: var(--muted); }
.chart .label { font: 500 11.5px var(--mono); fill: var(--ink-2); letter-spacing: .04em; }
.chart .press { fill: none; stroke-width: 2.4; stroke-linejoin: round; stroke-linecap: round; }
.chart .release { fill: none; stroke: var(--release); stroke-width: 1.6; stroke-dasharray: 5 4; stroke-linejoin: round; }
.chart .area { opacity: .08; }
.chart .marker { stroke: var(--ink-2); stroke-width: 1; stroke-dasharray: 3 3; }
.chart .marker-dot { stroke: var(--card); stroke-width: 2; }
.chart .note { font: 500 11.5px var(--mono); fill: var(--ink); }
.chart .note-bg { fill: var(--card); opacity: .9; }
.chart.animate .press { stroke-dasharray: var(--len, 2000); stroke-dashoffset: var(--len, 2000); animation: draw 1.4s cubic-bezier(.6, .1, .2, 1) forwards; }
.chart.animate .release { opacity: 0; animation: fade .6s 1.1s forwards; }
.chart.animate .area { opacity: 0; animation: fade-area .8s .9s forwards; }
@keyframes draw { to { stroke-dashoffset: 0; } }
@keyframes fade { to { opacity: 1; } }
@keyframes fade-area { to { opacity: .08; } }
.legend { display: flex; flex-wrap: wrap; gap: 18px; font: 12.5px var(--mono); color: var(--ink-2); }
.legend span { display: inline-flex; align-items: center; gap: 8px; }
.legend i { width: 18px; height: 0; border-top: 2.4px solid currentColor; display: inline-block; }
.legend i.dash { border-top: 1.6px dashed var(--release); }

/* Switch page */
.switch-head { padding-top: 56px; display: flex; gap: 24px; align-items: center; }
.switch-head .icon { width: 84px; height: 84px; flex: none; }
.switch-head h1 { margin: 6px 0 0; }
.crumbs { font: 13px var(--mono); color: var(--muted); margin-bottom: 6px; }
.crumbs a { text-decoration: none; }
.switch-layout { display: grid; grid-template-columns: 1fr 320px; gap: 24px; margin-top: 36px; align-items: start; }
.specs { margin: 0; display: grid; grid-template-columns: 1fr auto; }
.specs dt, .specs dd { padding: 11px 0; border-bottom: 1px solid var(--line); margin: 0; font-size: 14.5px; }
.specs dt { color: var(--ink-2); white-space: nowrap; padding-right: 16px; }
.specs dd { font-family: var(--mono); text-align: right; }
.specs dt:last-of-type, .specs dd:last-of-type { border-bottom: 0; }
.listen { display: flex; gap: 10px; margin-top: 18px; }
.listen button { flex: 1; justify-content: center; }
.listen button.playing { background: var(--accent); border-color: var(--accent); color: #fff; }
.side-actions { display: flex; flex-direction: column; gap: 10px; margin-top: 18px; }
.chart-card { padding: 24px 24px 16px; }
.chart-card .bar { display: flex; justify-content: space-between; align-items: center; margin-bottom: 8px; gap: 12px; flex-wrap: wrap; }
.related { margin-top: 48px; }

/* Table */
.toolbar { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 16px; }
.chip { font: 500 13.5px var(--sans); padding: 8px 14px; border-radius: 999px; border: 1px solid var(--line); background: var(--card); color: var(--ink-2); cursor: pointer; transition: all .15s; }
.chip:hover { border-color: var(--ink-2); color: var(--ink); }
.chip[aria-pressed="true"] { background: var(--ink); color: var(--paper); border-color: var(--ink); }
.table-wrap { overflow-x: auto; }
table { width: 100%; border-collapse: collapse; font-size: 14.5px; }
th { text-align: left; font: 500 12px var(--mono); letter-spacing: .06em; text-transform: uppercase; color: var(--muted); padding: 14px 16px; border-bottom: 1px solid var(--line); white-space: nowrap; }
th button { all: unset; cursor: pointer; display: inline-flex; gap: 6px; align-items: center; }
th button:hover { color: var(--ink); }
th button::after { content: "↕"; opacity: .35; font-size: 11px; }
th button[data-dir="asc"]::after { content: "↑"; opacity: 1; color: var(--accent); }
th button[data-dir="desc"]::after { content: "↓"; opacity: 1; color: var(--accent); }
td { padding: 12px 16px; border-bottom: 1px solid var(--line); white-space: nowrap; }
td.num { font-family: var(--mono); text-align: right; }
th.num { text-align: right; }
tbody tr { transition: background .12s; }
tbody tr:hover { background: var(--paper-2); }
tbody tr:last-child td { border-bottom: 0; }
td .name { display: flex; align-items: center; gap: 12px; text-decoration: none; font-weight: 500; }
td .name svg { width: 28px; height: 28px; }
td input[type="checkbox"] { accent-color: var(--accent); width: 16px; height: 16px; cursor: pointer; }

/* Compare */
.compare { margin-top: 24px; padding: 24px; }
#cmp-chart { max-width: 860px; margin: 0 auto; }
.compare .empty { padding: 48px 0; text-align: center; color: var(--muted); font-family: var(--mono); font-size: 14px; }

/* Prose */
.prose { max-width: 68ch; }
.prose h2 { margin-top: 1.8em; }
.prose p, .prose li { color: var(--ink-2); }
.prose strong { color: var(--ink); }
.prose figure { margin: 2em 0; }
.prose figcaption { font: 13px var(--mono); color: var(--muted); margin-top: 10px; }
.page-head { padding-top: 64px; }
.two-col { display: grid; grid-template-columns: 1fr 300px; gap: 48px; align-items: start; }
.aside { position: sticky; top: 96px; }
.aside h3 { font-size: 13px; font-family: var(--mono); text-transform: uppercase; letter-spacing: .1em; color: var(--muted); }
.aside ul { list-style: none; padding: 0; margin: 0; }
.aside li { padding: 8px 0; border-bottom: 1px solid var(--line); font-size: 14.5px; }
.aside li:last-child { border-bottom: 0; }
.note-list { display: grid; gap: 18px; }
.note-card { padding: 26px 28px; }
.note-card time { font: 13px var(--mono); color: var(--muted); }
.note-card h2 { font-size: 22px; margin: 6px 0 8px; }
.note-card p { margin: 0; color: var(--ink-2); }

/* Library + forms */
.library { display: grid; grid-template-columns: 1fr 400px; gap: 32px; align-items: start; margin-top: 40px; }
.pack { display: flex; gap: 18px; align-items: center; padding: 18px 22px; }
.pack + .pack { margin-top: 12px; }
.pack .glyph { width: 46px; height: 46px; border-radius: 12px; display: grid; place-items: center; background: var(--paper-2); color: var(--ink-2); flex: none; }
.pack .glyph svg { width: 22px; height: 22px; }
.pack h3 { margin: 0 0 2px; font-size: 16px; }
.pack p { margin: 0; font-size: 14px; color: var(--muted); }
.pack .size { margin-left: auto; font: 13px var(--mono); color: var(--ink-2); display: flex; align-items: center; gap: 8px; white-space: nowrap; }
.pack .size svg { width: 14px; height: 14px; color: var(--muted); }
.signin { padding: 32px; position: sticky; top: 96px; }
.signin h2 { font-size: 22px; }
.field { display: block; margin-bottom: 16px; }
.field span { display: block; font-size: 13.5px; font-weight: 500; margin-bottom: 6px; }
.field input {
  width: 100%; font: 15px var(--sans); color: var(--ink);
  padding: 12px 14px; border-radius: var(--radius-sm);
  border: 1px solid var(--line); background: var(--paper);
  transition: border-color .15s, box-shadow .15s;
}
.field input:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 4px var(--accent-soft); }
.form-row { display: flex; justify-content: space-between; align-items: center; font-size: 14px; margin: -4px 0 20px; }
.form-row label { display: flex; gap: 8px; align-items: center; color: var(--ink-2); }
.form-row input { accent-color: var(--accent); }
.signin .btn { width: 100%; justify-content: center; padding: 13px; }
.form-msg { min-height: 22px; font-size: 14px; margin: 14px 0 0; }
.form-msg.error { color: var(--clicky); }
.form-msg.ok { color: var(--ink-2); }
.spinner { width: 15px; height: 15px; border-radius: 50%; border: 2px solid currentColor; border-right-color: transparent; animation: spin .7s linear infinite; display: none; }
.btn[disabled] .spinner { display: inline-block; }
@keyframes spin { to { transform: rotate(360deg); } }
.fine { font-size: 13px; color: var(--muted); margin-top: 18px; line-height: 1.5; }

/* Footer */
.site-footer { border-top: 1px solid var(--line); padding: 36px 0 48px; font-size: 14px; color: var(--muted); background: color-mix(in srgb, var(--paper) 85%, transparent); }
.site-footer .wrap { display: flex; justify-content: space-between; gap: 24px; flex-wrap: wrap; }
.site-footer nav { display: flex; gap: 20px; }
.site-footer a { text-decoration: none; }

/* 404 */
.notfound { text-align: center; padding: 120px 0 40px; }
.notfound .code { font: 500 14px var(--mono); color: var(--accent); letter-spacing: .2em; }

/* Reveal on scroll */
.reveal { opacity: 0; transform: translateY(14px); transition: opacity .6s ease, transform .6s ease; }
.reveal.in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; }
  .reveal { opacity: 1; transform: none; }
  .chart.animate .press { stroke-dashoffset: 0; }
  .chart.animate .release { opacity: 1; }
}

/* Responsive */
@media (max-width: 900px) {
  .hero, .switch-layout, .two-col, .library { grid-template-columns: 1fr; }
  .hero { padding-top: 40px; gap: 32px; }
  .aside, .signin { position: static; }
  .nav { display: none; position: absolute; top: 64px; left: 0; right: 0; flex-direction: column; align-items: stretch; padding: 12px 24px 20px; background: var(--paper); border-bottom: 1px solid var(--line); }
  .nav.open { display: flex; }
  .nav .btn { margin: 8px 0 0; justify-content: center; }
  .nav-toggle { display: inline-flex; margin-left: auto; background: none; border: 1px solid var(--line); border-radius: 10px; padding: 8px 10px; color: var(--ink); cursor: pointer; }
  .stats { gap: 24px; }
  .section-head { flex-direction: column; align-items: start; }
}