/* K1 V1.0: design from Claude Design (K1 Design Board), built by Escrivão. */
/* Fonts: Newsreader + Instrument Sans (OFL), self-hosted. */
/* latin-ext */
@font-face {
  font-family: 'Instrument Sans';
  font-style: normal;
  font-weight: 400 600;
  font-stretch: 100%;
  font-display: swap;
  src: url(/assets/fonts/InstrumentSans-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-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
/* latin */
@font-face {
  font-family: 'Instrument Sans';
  font-style: normal;
  font-weight: 400 600;
  font-stretch: 100%;
  font-display: swap;
  src: url(/assets/fonts/InstrumentSans-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;
}
/* latin-ext */
@font-face {
  font-family: 'Newsreader';
  font-style: italic;
  font-weight: 400 600;
  font-display: swap;
  src: url(/assets/fonts/Newsreader-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-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
/* latin */
@font-face {
  font-family: 'Newsreader';
  font-style: italic;
  font-weight: 400 600;
  font-display: swap;
  src: url(/assets/fonts/Newsreader-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;
}
/* latin-ext */
@font-face {
  font-family: 'Newsreader';
  font-style: normal;
  font-weight: 400 600;
  font-display: swap;
  src: url(/assets/fonts/Newsreader-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-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
/* latin */
@font-face {
  font-family: 'Newsreader';
  font-style: normal;
  font-weight: 400 600;
  font-display: swap;
  src: url(/assets/fonts/Newsreader-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;
}

/* ── Tokens ─────────────────────────────────────────────────────────── */
:root {
  --k-bg:#F7F3EA; --k-surface:#EFE8DA; --k-try:#F1E2CF; --k-ink:#1D1A16; --k-ink-2:#4F483F; --k-ink-3:#6B6257;
  --k-rule:#DCD2C1; --k-accent:#B23C1C; --k-on-accent:#FFF8F0;
  --k-serif:'Newsreader', Georgia, 'Times New Roman', serif;
  --k-sans:'Instrument Sans', system-ui, -apple-system, 'Segoe UI', sans-serif;
  --k-mono:ui-monospace, Menlo, Consolas, monospace;
  --k-gutter:clamp(20px, 5vw, 48px);
  color-scheme:light;
}
:root[data-theme="dark"] {
  --k-bg:#14120F; --k-surface:#1E1B17; --k-try:#28201A; --k-ink:#EDE6D8; --k-ink-2:#C4BAAA; --k-ink-3:#9C9283;
  --k-rule:#34302A; --k-accent:#F08A68; --k-on-accent:#1A0E08; color-scheme:dark;
}
/* Without JavaScript, follow the system setting. */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme]) {
    --k-bg:#14120F; --k-surface:#1E1B17; --k-try:#28201A; --k-ink:#EDE6D8; --k-ink-2:#C4BAAA; --k-ink-3:#9C9283;
    --k-rule:#34302A; --k-accent:#F08A68; --k-on-accent:#1A0E08; color-scheme:dark;
  }
}

/* ── Base ───────────────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing:border-box; }
html { background:var(--k-bg); -webkit-text-size-adjust:100%; text-size-adjust:100%; }
body { margin:0; min-height:100vh; display:flex; flex-direction:column; background:var(--k-bg); color:var(--k-ink);
  font-family:var(--k-serif); transition:background-color .3s, color .3s; -webkit-font-smoothing:antialiased; }
main { flex:1; width:100%; outline:none; }
a { color:inherit; }
a:hover { color:var(--k-accent); }
:focus-visible { outline:2px solid var(--k-accent); outline-offset:3px; border-radius:2px; }
::selection { background:var(--k-accent); color:var(--k-on-accent); }
.k1-wrap { width:100%; max-width:1120px; margin-inline:auto; padding-inline:var(--k-gutter); }
html:not(.js) .k1-js-only { display:none !important; }
html.js .k1-nojs-only { display:none !important; }

.k1-skip { position:absolute; left:-9999px; top:12px; z-index:10; background:var(--k-ink); color:var(--k-bg);
  padding:10px 16px; font:15px var(--k-sans); border-radius:4px; text-decoration:none; }
.k1-skip:focus { left:12px; color:var(--k-bg); }

/* ── Header ─────────────────────────────────────────────────────────── */
.k1-header { padding-block:18px; display:flex; align-items:center; justify-content:space-between; gap:12px 20px; flex-wrap:wrap; }
.k1-logo { display:inline-flex; align-items:flex-start; min-height:44px; padding-top:5px; text-decoration:none; color:var(--k-ink);
  font:600 34px/1 var(--k-serif); letter-spacing:-0.03em; }
.k1-logo span { font-size:.52em; color:var(--k-accent); margin:-0.08em 0 0 .04em; }
.k1-logo:hover { color:var(--k-ink); }
.k1-nav { display:flex; align-items:center; gap:clamp(6px, 2vw, 22px); flex-wrap:wrap; font:15px var(--k-sans); }
.k1-nav > a { color:var(--k-ink-2); text-decoration:none; min-height:44px; display:flex; align-items:center; padding:0 4px; }
.k1-nav > a:hover, .k1-nav > a[aria-current] { color:var(--k-accent); }
.k1-lang { display:flex; border:1px solid var(--k-rule); border-radius:999px; padding:2px; }
.k1-lang a { min-width:40px; height:38px; display:flex; align-items:center; justify-content:center; border-radius:999px;
  text-decoration:none; font-size:13px; font-weight:600; letter-spacing:.06em; color:var(--k-ink-2); }
.k1-lang a[aria-current] { background:var(--k-ink); color:var(--k-bg); }
.k1-theme { width:44px; height:44px; border-radius:50%; border:1px solid var(--k-rule); background:transparent; color:var(--k-ink);
  display:flex; align-items:center; justify-content:center; cursor:pointer; padding:0; }
.k1-theme:hover { border-color:var(--k-ink-3); }
:root[data-theme="dark"] .k1-i-moon, :root:not([data-theme="dark"]) .k1-i-sun { display:none; }

/* ── Home ───────────────────────────────────────────────────────────── */
.k1-hero { padding-top:clamp(40px, 9vw, 112px); padding-bottom:clamp(36px, 6vw, 64px); }
.k1-hero h1 { margin:0; font-weight:400; font-size:clamp(46px, 8.4vw, 104px); line-height:.98; letter-spacing:-0.03em;
  text-wrap:balance; max-width:11ch; }
.k1-hero h1 em { color:var(--k-accent); }
.k1-hero p { margin:clamp(20px, 3vw, 32px) 0 0; font-size:clamp(19px, 2vw, 24px); line-height:1.45; color:var(--k-ink-2);
  max-width:30ch; text-wrap:pretty; }
.k1-list ol { list-style:none; margin:0; padding:0; border-top:1px solid var(--k-rule); }
.k1-list li { border-bottom:1px solid var(--k-rule); }
.k1-list li a { display:flex; flex-direction:column; gap:12px; padding:clamp(22px, 3vw, 34px) 0; text-decoration:none;
  color:var(--k-ink); transition:color .2s; }
.k1-list li a:hover { color:var(--k-accent); }
.k1-list-title { font-size:clamp(26px, 3.7vw, 42px); font-weight:500; line-height:1.12; letter-spacing:-0.015em;
  text-wrap:balance; max-width:24ch; }
.k1-meta { display:flex; align-items:center; gap:10px; margin:0; font:13px var(--k-sans); letter-spacing:.07em;
  text-transform:uppercase; color:var(--k-ink-3); }
.k1-dot { width:9px; height:9px; border-radius:50%; border:1.5px solid var(--k-accent); flex:none; }
.k1-dot.is-exp { background:var(--k-accent); }
.k1-notsure { margin:clamp(28px, 4vw, 44px) 0 0; font-size:clamp(18px, 1.6vw, 21px); font-style:italic; color:var(--k-ink-2); }
.k1-notsure a { color:var(--k-accent); font:500 .85em var(--k-sans); text-underline-offset:.2em; }

/* ── Article ────────────────────────────────────────────────────────── */
.k1-article { padding-top:clamp(32px, 6vw, 80px); }
.k1-article-head { max-width:800px; margin-bottom:clamp(28px, 4vw, 48px); }
.k1-article-head .k1-meta { margin-bottom:20px; }
.k1-article-head h1 { margin:0; font-weight:500; font-size:clamp(36px, 5.6vw, 62px); line-height:1.06; letter-spacing:-0.022em; text-wrap:balance; }
.k1-lede { margin:18px 0 0; font-size:clamp(21px, 2.2vw, 27px); line-height:1.35; font-style:italic; color:var(--k-ink-2); }

.k1-prose { max-width:34em; font-size:clamp(18px, 0.6vw + 15px, 21px); line-height:1.65; }
.k1-prose p { margin:0 0 1.1em; text-wrap:pretty; hanging-punctuation:first; }
.k1-prose a { color:inherit; text-decoration-color:var(--k-accent); text-decoration-thickness:1px; text-underline-offset:.18em; }
.k1-prose a:hover { color:var(--k-accent); }
.k1-prose strong { font-weight:600; }
.k1-prose a.k1-int { color:var(--k-accent); text-decoration-style:dotted; text-decoration-thickness:2px; text-underline-offset:.24em; }
.k1-prose a.k1-int:hover { text-decoration-style:solid; }
.k1-int-q { display:inline-flex; align-items:center; justify-content:center; width:1.05em; height:1.05em; margin-left:.3em;
  border-radius:50%; background:var(--k-accent); color:var(--k-on-accent); font:600 .62em var(--k-sans); vertical-align:.35em; }
.k1-prose h2 { margin:2.1em 0 .7em; font-size:1.42em; font-weight:600; line-height:1.2; letter-spacing:-0.01em; text-wrap:balance;
  display:flex; flex-direction:column; gap:.55em; }
.k1-prose h2::before { content:""; width:28px; height:2px; background:var(--k-accent); }
.k1-prose ul { margin:0 0 1.2em; padding-left:1.1em; display:flex; flex-direction:column; gap:.5em; }
.k1-prose li { padding-left:.2em; text-wrap:pretty; }

.k1-quote { margin:1.9em 0 2em; padding:0 0 0 1.3em; position:relative; }
.k1-quote-mark { position:absolute; left:-0.08em; top:-0.18em; font-size:3.2em; line-height:1; color:var(--k-accent); font-style:normal; }
.k1-quote blockquote { margin:0; font-size:1.2em; line-height:1.5; font-style:italic; text-wrap:pretty; }
.k1-quote blockquote p { margin:0; }
.k1-quote figcaption, .k1-figure figcaption { margin-top:.9em; font:14px/1.5 var(--k-sans); color:var(--k-ink-3); }
.k1-figure { margin:2em 0; }
.k1-figure img { width:100%; height:auto; border-radius:6px; display:block; }

.k1-try { margin:2.4em 0; padding:clamp(22px, 3vw, 34px) clamp(20px, 3vw, 36px) clamp(8px, 1vw, 14px); background:var(--k-try); border-radius:8px; }
.k1-prose .k1-try-label { margin:0 0 1em; display:flex; align-items:center; gap:10px; font:600 13px var(--k-sans);
  letter-spacing:.09em; text-transform:uppercase; color:var(--k-accent); }
.k1-try p { margin:0 0 1em; }

.k1-reasoning { margin:1.6em 0 0; border-top:1px solid var(--k-rule); border-bottom:1px solid var(--k-rule); }
.k1-reasoning summary { cursor:pointer; min-height:44px; display:list-item; padding:14px 0; font:600 16px var(--k-sans); }
.k1-reasoning summary::marker { color:var(--k-accent); }
.k1-reasoning > div { padding:4px 0 18px; }
.k1-reasoning p { margin:0 0 .9em; }

.k1-sources { margin:3.2em 0 0; padding-top:1.4em; border-top:1px solid var(--k-rule); font-family:var(--k-sans); }
.k1-prose .k1-sources h2 { margin:0 0 14px; display:block; font:600 13px var(--k-sans); letter-spacing:.09em; text-transform:uppercase; color:var(--k-ink-3); }
.k1-prose .k1-sources h2::before { content:none; }
.k1-sources ol { margin:0; padding-left:1.4em; display:flex; flex-direction:column; gap:10px; font-size:14.5px; line-height:1.5; color:var(--k-ink-2); }
.k1-sources li { padding-left:.2em; overflow-wrap:anywhere; }
.k1-prose .k1-sources a { color:var(--k-ink-2); text-decoration-color:var(--k-rule); text-underline-offset:.2em; }
.k1-prose .k1-sources a:hover { color:var(--k-accent); text-decoration-color:var(--k-accent); }
.k1-sources em { font-family:var(--k-serif); font-size:1.08em; }
.k1-src-domain { color:var(--k-ink-3); }

.k1-next { max-width:800px; margin:clamp(48px, 7vw, 88px) 0 0; padding-top:24px; border-top:1px solid var(--k-rule); }
.k1-next p { margin:0 0 10px; font:600 13px var(--k-sans); letter-spacing:.09em; text-transform:uppercase; color:var(--k-ink-3); }
.k1-next a { display:block; font-size:clamp(26px, 3.4vw, 38px); font-weight:500; line-height:1.15; letter-spacing:-0.015em;
  text-decoration:none; color:var(--k-ink); text-wrap:balance; transition:color .2s; }
.k1-next a:hover { color:var(--k-accent); }
.k1-next a span { color:var(--k-accent); }
.k1-actions { display:flex; flex-wrap:wrap; gap:12px; margin-top:8px; }

/* ── Buttons ────────────────────────────────────────────────────────── */
.k1-btn { min-height:44px; padding:0 18px; border-radius:999px; border:1px solid var(--k-ink); background:transparent; color:var(--k-ink);
  font:500 15px var(--k-sans); cursor:pointer; display:inline-flex; align-items:center; gap:8px; text-decoration:none;
  transition:background-color .2s, color .2s; }
.k1-btn:hover { background:var(--k-ink); color:var(--k-bg); }
.k1-btn-solid { background:var(--k-ink); color:var(--k-bg); }
.k1-btn-solid:hover { color:var(--k-bg); }
.k1-btn-accent { background:var(--k-accent); color:var(--k-on-accent); border:0; font-weight:600; }
.k1-btn-accent:hover { background:var(--k-accent); color:var(--k-on-accent); filter:brightness(1.08); }

/* ── Experiment ─────────────────────────────────────────────────────── */
.k1-exp { margin:2.2em 0 2.6em; width:min(1000px, calc(100vw - 2 * var(--k-gutter))); background:var(--k-surface); border-radius:10px;
  padding:clamp(22px, 3.5vw, 40px); display:grid; grid-template-columns:repeat(auto-fit, minmax(min(100%, 300px), 1fr));
  gap:clamp(28px, 4vw, 52px); font:15px/1.5 var(--k-sans); }
.k1-prose .k1-exp p { margin:0; }
.k1-exp-controls { display:flex; flex-direction:column; gap:26px; }
.k1-exp-field { display:flex; flex-direction:column; gap:6px; }
.k1-exp-field label { display:flex; justify-content:space-between; align-items:baseline; gap:12px; color:var(--k-ink-2); }
.k1-exp-field output { font:500 28px var(--k-serif); color:var(--k-ink); }
.k1-exp input[type=range] { width:100%; height:44px; margin:0; cursor:pointer; accent-color:var(--k-accent); }
.k1-exp-result { border-top:1px solid var(--k-rule); padding-top:22px; }
.k1-prose .k1-exp-pct { font:500 clamp(64px, 9vw, 104px)/.95 var(--k-serif); letter-spacing:-0.035em; font-variant-numeric:lining-nums tabular-nums; }
.k1-prose .k1-exp-at { margin-top:10px; font-size:17px; font-weight:500; }
.k1-prose .k1-exp-sub { margin-top:6px; color:var(--k-ink-2); text-wrap:pretty; }
.k1-exp-run { display:flex; flex-direction:column; gap:14px; min-width:0; }
.k1-exp-run-head { display:flex; justify-content:space-between; align-items:center; gap:12px; }
.k1-exp-run h3 { margin:0; font:600 13px var(--k-sans); letter-spacing:.09em; text-transform:uppercase; color:var(--k-ink-2); }
.k1-prose .k1-exp-caption { color:var(--k-ink-3); font-size:14px; }
.k1-exp-grid { display:grid; gap:5px; }
.k1-exp-grid span { aspect-ratio:1; border-radius:3px; box-shadow:inset 0 0 0 1px var(--k-rule); }
.k1-exp-grid span.hit { background:var(--k-accent); box-shadow:inset 0 0 0 1px var(--k-accent); }
.k1-prose .k1-exp-tally { margin-top:4px; font-size:16px; }
.k1-prose .k1-exp-many { color:var(--k-ink-2); font-size:14px; }
.k1-exp-share { grid-column:1 / -1; border-top:1px solid var(--k-rule); padding-top:20px; display:flex; flex-wrap:wrap; align-items:center; gap:10px 14px; }
.k1-exp-share label { font-size:14px; color:var(--k-ink-2); }
.k1-exp-share input { flex:1 1 240px; min-width:0; min-height:44px; padding:0 14px; border:1px solid var(--k-rule); border-radius:6px;
  background:var(--k-bg); color:var(--k-ink-2); font:14px var(--k-mono); }

/* ── Footer ─────────────────────────────────────────────────────────── */
.k1-footer { margin-top:clamp(64px, 9vw, 120px); padding-block:28px 40px; }
.k1-footer > div { border-top:1px solid var(--k-rule); padding-top:24px; display:flex; flex-wrap:wrap; justify-content:space-between;
  align-items:baseline; gap:10px 24px; font:14px var(--k-sans); color:var(--k-ink-3); }
.k1-footer a { color:var(--k-ink-2); text-underline-offset:.2em; }
.k1-footer a:hover { color:var(--k-accent); }
.k1-footer-tag { font:italic 16px var(--k-serif); color:var(--k-ink-2); }

@media (prefers-reduced-motion: reduce) { *, *::before, *::after { transition:none !important; animation:none !important; } }
.k1-exp-grid.dense span { border-radius:1px; }