/* Four Tones - cool slate and jade, tone colours shared by every drawing: 1 red, 2 amber, 3 green, 4 blue, light grey. */
:root {
  --bg: #eef2f0; --card: #ffffff; --card2: #f6f8f7; --ink: #15201d; --soft: #3b4945; --muted: #66746f; --line: #d5dedb; --line2: #b9c6c2;
  --accent: #0b7d68; --accent-ink: #ffffff; --accent-soft: #d9efe9; --band: #14231f; --band-ink: #e8f2ef;
  --t1: #d4433a; --t2: #d98a12; --t3: #23955a; --t4: #2f64d0; --t5: #8b949b; --t0: #b0b8bd;
  --ok: #1f7a4d; --okbg: #e3f4ea; --warn: #9a5b00; --warnbg: #fdf1dc; --err: #b3261e; --errbg: #fbe4e2; --info: #285c9c; --infobg: #e4eefa;
  --mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Noto Sans SC", sans-serif;
  --han: "PingFang SC", "Hiragino Sans GB", "Noto Sans SC", "Microsoft YaHei", "Songti SC", serif;
  color-scheme: light;
}
:root[data-theme="dark"] {
  --bg: #0e1513; --card: #151f1c; --card2: #1a2622; --ink: #e6efec; --soft: #c2d0cb; --muted: #8c9c97; --line: #2a3833; --line2: #3b4b46;
  --accent: #2fc0a0; --accent-ink: #062019; --accent-soft: #143a31; --band: #070c0b; --band-ink: #d7e6e1;
  --t1: #ff6b61; --t2: #f2b640; --t3: #4fd18a; --t4: #6e9bff; --t5: #9aa4ab; --t0: #5d676c;
  --ok: #5fd19a; --okbg: #12301f; --warn: #f2b640; --warnbg: #33270e; --err: #ff8a80; --errbg: #3a1714; --info: #8fb8f0; --infobg: #13243a;
  color-scheme: dark;
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body { margin: 0; background: var(--bg); color: var(--ink); font: 16px/1.55 var(--sans); }
a { color: var(--accent); }
h1, h2, h3, h4 { line-height: 1.2; margin: 0 0 .4em; }
.hidden { display: none !important; }
.small { font-size: 13.5px; }
.muted { color: var(--muted); }
.mono { font-family: var(--mono); overflow-wrap: anywhere; }
button { font: inherit; color: inherit; }

/* header */
.bar { display: flex; align-items: center; gap: 14px; padding: 10px 22px; background: var(--band); color: var(--band-ink); position: sticky; top: 0; z-index: 20; }
.back { color: var(--band-ink); opacity: .75; text-decoration: none; font-size: 14px; }
.brand { display: flex; align-items: center; gap: 10px; font-size: 18px; flex: 1; }
.seal { font-family: var(--han); background: var(--accent); color: var(--accent-ink); border-radius: 8px; padding: 2px 7px; font-size: 15px; letter-spacing: 1px; }
.session { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; justify-content: flex-end; }
.credits { font-size: 13px; opacity: .85; }
.bar .pill { border-color: rgba(255,255,255,.28); color: var(--band-ink); background: transparent; }
.bar .pill.solid { background: var(--accent); color: var(--accent-ink); border-color: var(--accent); }
.pill { display: inline-flex; align-items: center; justify-content: center; gap: 6px; border: 1px solid var(--line2); background: var(--card); color: var(--ink); border-radius: 999px; padding: 7px 15px; font-size: 14px; cursor: pointer; text-decoration: none; min-height: 36px; }
.pill:hover:not(:disabled) { border-color: var(--accent); }
.pill.solid { background: var(--accent); color: var(--accent-ink); border-color: var(--accent); font-weight: 600; }
.pill.big { padding: 11px 24px; font-size: 16px; }
.pill.tiny { padding: 4px 11px; font-size: 13px; min-height: 30px; }
.pill:disabled { opacity: .45; cursor: not-allowed; }

/* hero */
.hero { max-width: 1100px; margin: 0 auto; padding: 36px 22px 18px; display: grid; grid-template-columns: 1.1fr 1fr; gap: 10px 34px; align-items: center; }
.kicker { font-family: var(--mono); font-size: 13px; color: var(--accent); letter-spacing: .04em; margin: 0 0 8px; }
.hero h1 { font-size: 40px; font-weight: 750; letter-spacing: -.01em; }
.hero h1 em { font-style: normal; color: var(--accent); }
.sub { color: var(--soft); max-width: 560px; margin: 10px 0 0; }
.tonepad { display: grid; grid-template-columns: repeat(5, 1fr); gap: 8px; }
.tbtn { position: relative; border: 2px solid var(--line); background: var(--card); border-radius: 18px; padding: 16px 4px 12px; cursor: pointer; display: flex; flex-direction: column; align-items: center; gap: 4px; transition: transform .15s, border-color .15s; }
.tbtn:hover { transform: translateY(-2px); }
.tbtn .tmark { font-size: 30px; font-weight: 700; font-family: var(--sans); }
.tbtn .tname { font-size: 12px; color: var(--muted); }
.tbtn::before { content: ""; width: 34px; height: 22px; background: no-repeat center / contain; }
.tbtn.t1 .tmark { color: var(--t1); } .tbtn.t2 .tmark { color: var(--t2); } .tbtn.t3 .tmark { color: var(--t3); } .tbtn.t4 .tmark { color: var(--t4); } .tbtn.t5 .tmark { color: var(--t5); }
.tbtn.t1::before { border-top: 3px solid var(--t1); height: 0; margin: 10px 0 9px; }
.tbtn.t2::before { background: linear-gradient(to bottom right, transparent 46%, var(--t2) 47%, var(--t2) 53%, transparent 54%); }
.tbtn.t3::before { background: radial-gradient(ellipse 60% 120% at 50% 0%, transparent 62%, var(--t3) 64%, var(--t3) 74%, transparent 76%); }
.tbtn.t4::before { background: linear-gradient(to top right, transparent 46%, var(--t4) 47%, var(--t4) 53%, transparent 54%); }
.tbtn.t5::before { width: 9px; height: 9px; border-radius: 50%; background: var(--t5); margin: 6px 0 7px; }
.tbtn.ring { border-color: var(--accent); box-shadow: 0 0 0 4px var(--accent-soft); }
.voicerow { grid-column: 2; display: flex; flex-wrap: wrap; align-items: center; gap: 12px; }
.mini-field { font-size: 13px; color: var(--muted); display: inline-flex; align-items: center; gap: 6px; }
select, input[type="text"], textarea { font: inherit; color: var(--ink); background: var(--card); border: 1px solid var(--line2); border-radius: 10px; padding: 9px 11px; width: 100%; min-width: 0; }
.mini-field select { width: auto; padding: 5px 8px; }
textarea { resize: vertical; }
input:focus, select:focus, textarea:focus, button:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }

/* blocks */
.wrap { max-width: 1100px; margin: 0 auto; padding: 0 22px 40px; }
.block { margin: 28px 0; }
.bhead h2 { font-size: 23px; display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }
.bhead p { color: var(--muted); margin: 0 0 12px; max-width: 760px; }
.num { display: inline-grid; place-items: center; width: 30px; height: 30px; border-radius: 50%; background: var(--ink); color: var(--bg); font-size: 15px; font-family: var(--mono); }
.paid { font-size: 12px; font-family: var(--mono); background: var(--accent-soft); color: var(--accent); border-radius: 6px; padding: 2px 7px; }
.panel { background: var(--card); border: 1px solid var(--line); border-radius: 18px; padding: 18px; }
.examples { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin-bottom: 12px; }
.ex-label { font-size: 13px; color: var(--muted); }
.chip { border: 1px dashed var(--line2); background: var(--card2); border-radius: 999px; padding: 5px 12px; font-size: 13.5px; cursor: pointer; }
.chip.on { border-style: solid; border-color: var(--accent); background: var(--accent-soft); color: var(--accent); }
.row2 { display: grid; grid-template-columns: 1.4fr 1fr; gap: 12px; }
.row3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; }
.field { display: flex; flex-direction: column; gap: 5px; font-size: 14px; font-weight: 600; color: var(--soft); margin-bottom: 10px; }
.field input, .field select, .field textarea { font-weight: 400; }
.field.wide { width: 100%; }
.check { display: flex; align-items: center; gap: 8px; font-size: 14px; color: var(--soft); margin: 4px 0 10px; }
.runrow { display: flex; flex-wrap: wrap; gap: 8px; margin: 12px 0 4px; }

/* staff */
.staffwrap { overflow-x: auto; background: var(--card2); border: 1px solid var(--line); border-radius: 14px; padding: 6px; -webkit-overflow-scrolling: touch; }
.staff { display: block; max-width: none; }
.staff-line { stroke: var(--line2); stroke-width: 1; }
.staff-line.mid { stroke-dasharray: 3 4; }
.staff-num { fill: var(--muted); font: 11px var(--mono); text-anchor: middle; }
.staff-empty { fill: var(--muted); font: 14px var(--sans); }
.syl .cellbg { fill: transparent; }
.syl.active .cellbg { fill: var(--accent-soft); }
.syl.invalid .cellbg { fill: var(--errbg); }
.han { font: 20px var(--han); fill: var(--ink); text-anchor: middle; }
.cont { fill: none; stroke-width: 5; stroke-linecap: round; stroke-linejoin: round; }
.ghost { fill: none; stroke-width: 2; stroke-dasharray: 4 5; opacity: .7; stroke-linecap: round; }
.t1.cont, .t1.ghost { stroke: var(--t1); } .t2.cont, .t2.ghost { stroke: var(--t2); } .t3.cont, .t3.ghost { stroke: var(--t3); } .t4.cont, .t4.ghost { stroke: var(--t4); } .t5.cont { stroke: var(--t5); } .t0.cont { stroke: var(--t0); }
.py { font: 600 15px var(--sans); text-anchor: middle; }
text.t1 { fill: var(--t1); } text.t2 { fill: var(--t2); } text.t3 { fill: var(--t3); } text.t4 { fill: var(--t4); } text.t5 { fill: var(--t5); } text.t0 { fill: var(--t0); }
.said { font: 11px var(--sans); fill: var(--muted); text-anchor: middle; }
.said.changed { fill: var(--accent); font-weight: 700; }
.legend { color: var(--muted); margin: 8px 2px 0; }
.lg { display: inline-block; width: 22px; height: 0; vertical-align: middle; border-top: 4px solid var(--t3); border-radius: 2px; }
.lg.dash { border-top: 2px dashed var(--t3); }
.facts { list-style: none; margin: 10px 0 0; padding: 0; display: grid; gap: 6px; }
.facts li, .recon li { padding: 7px 11px; border-radius: 10px; font-size: 14px; border-left: 4px solid var(--line2); background: var(--card2); }
li.ok { border-left-color: var(--ok); background: var(--okbg); } li.info { border-left-color: var(--info); background: var(--infobg); }
li.warn { border-left-color: var(--warn); background: var(--warnbg); } li.error { border-left-color: var(--err); background: var(--errbg); }
li.none { color: var(--muted); list-style: none; }

/* drill */
.drilltop { display: flex; flex-wrap: wrap; align-items: center; gap: 10px; }
.seg { display: inline-flex; background: var(--card2); border: 1px solid var(--line); border-radius: 999px; padding: 3px; }
.segb { border: 0; background: transparent; border-radius: 999px; padding: 6px 16px; cursor: pointer; font-size: 14px; }
.segb.on { background: var(--ink); color: var(--bg); }
.score { font-family: var(--mono); font-size: 13px; color: var(--muted); margin-left: auto; }
.drillmsg { margin: 12px 0; min-height: 1.5em; font-size: 15px; }
.grid { display: grid; grid-template-columns: 52px repeat(5, minmax(0, 1fr)); gap: 6px; }
.ghead { font: 12px var(--mono); color: var(--muted); text-align: center; align-self: end; padding-bottom: 2px; }
.grow { font: 600 13px var(--mono); display: grid; place-items: center; border-radius: 10px; background: var(--card2); }
.grow.t1 { color: var(--t1); } .grow.t2 { color: var(--t2); } .grow.t3 { color: var(--t3); } .grow.t4 { color: var(--t4); }
.gcell { border: 1px solid var(--line); background: var(--card); border-radius: 12px; padding: 8px 4px 6px; cursor: pointer; display: grid; justify-items: center; gap: 1px; min-height: 76px; position: relative; }
.gcell:hover { border-color: var(--accent); }
.gid { font: 11px var(--mono); color: var(--muted); }
.gword { font: 19px var(--han); min-height: 26px; }
.gpy { font-size: 12.5px; color: var(--soft); }
.gacc { font: 10.5px var(--mono); color: var(--muted); min-height: 14px; }
.gcell.hgood { background: var(--okbg); } .gcell.hok { background: var(--infobg); } .gcell.hweak { background: var(--warnbg); border-color: var(--warn); }
.gcell.right { outline: 3px solid var(--ok); } .gcell.wrong { outline: 3px solid var(--err); } .gcell.asked { outline: 3px dashed var(--ok); }
.drillfoot { display: flex; flex-wrap: wrap; justify-content: space-between; align-items: center; gap: 8px; margin-top: 12px; }
.drillfoot p { margin: 0; flex: 1 1 280px; }
.exports { display: flex; flex-wrap: wrap; gap: 8px; }

/* ask */
.lanes { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin-bottom: 12px; }
.lane { text-align: left; border: 2px solid var(--line); background: var(--card); border-radius: 16px; padding: 12px 16px; cursor: pointer; display: flex; flex-direction: column; gap: 2px; }
.lane b { font-size: 16px; } .lane span { font-size: 13px; color: var(--muted); }
.lane.on { border-color: var(--accent); background: var(--accent-soft); }
.askform { background: var(--card); border: 1px solid var(--line); border-radius: 18px; padding: 18px; }
.note { background: var(--warnbg); color: var(--ink); border-radius: 10px; padding: 8px 12px; font-size: 14px; margin: 8px 0; }
.meter { font-size: 14px; color: var(--soft); margin: 10px 0 4px; }
.gate { background: var(--infobg); border-radius: 10px; padding: 9px 12px; font-size: 14px; margin: 8px 0; }
.gate .pill { margin-left: 4px; min-height: 30px; padding: 3px 12px; }
.progress { background: var(--card); border: 1px solid var(--line); border-radius: 16px; padding: 14px 18px; margin: 14px 0; }
.ptitle { font-weight: 700; margin: 0 0 6px; }
.steps { list-style: none; padding: 0; margin: 0; display: grid; gap: 3px; font-size: 14px; }
.step { color: var(--muted); } .step.done { color: var(--ok); } .step.active { color: var(--ink); font-weight: 600; }
.step-ic { display: inline-block; width: 16px; font-family: var(--mono); }
.raw { white-space: pre-wrap; background: var(--card2); border: 1px solid var(--line); border-radius: 10px; padding: 12px; font-size: 12.5px; max-height: 360px; overflow: auto; }

/* results */
.result { background: var(--card); border: 1px solid var(--line); border-radius: 18px; padding: 18px; margin: 16px 0; }
.rhead { display: flex; gap: 16px; align-items: flex-start; margin-bottom: 12px; }
.rhead h3 { font-size: 20px; } .rhead p { margin: 0 0 4px; }
.stamp { flex: none; font: 700 13px var(--mono); text-transform: uppercase; letter-spacing: .05em; padding: 10px 12px; border-radius: 12px; border: 2px solid currentColor; min-width: 96px; text-align: center; }
.v-light, .v-spot_on { color: var(--ok); background: var(--okbg); }
.v-moderate, .v-minor_slips { color: var(--warn); background: var(--warnbg); }
.v-heavy, .v-needs_work { color: var(--err); background: var(--errbg); }
.v-none { color: var(--muted); }
.phrases { list-style: none; padding: 0; margin: 0 0 14px; display: grid; grid-template-columns: repeat(auto-fill, minmax(290px, 1fr)); gap: 10px; }
.pcard { border: 1px solid var(--line); border-radius: 14px; padding: 12px 14px; background: var(--card2); display: flex; flex-direction: column; gap: 4px; }
.ptop { display: flex; align-items: center; gap: 10px; }
.pnum { font: 12px var(--mono); color: var(--muted); }
.phan { font-family: var(--han); font-size: 24px; flex: 1; }
.phan.small { font-size: 17px; flex: none; }
.mini { flex: none; }
.mini .cont { stroke-width: 3; }
.pyline { font-weight: 600; font-size: 16px; }
.pyline .t1 { color: var(--t1); } .pyline .t2 { color: var(--t2); } .pyline .t3 { color: var(--t3); } .pyline .t4 { color: var(--t4); } .pyline .t5, .pyline .t0 { color: var(--t5); }
.pyline .bad { text-decoration: wavy underline var(--err); }
.pyline .chg { border-bottom: 2px solid var(--accent); }
.psaid { margin: 0; font-size: 13px; color: var(--muted); }
.psaid .pyline { font-size: 14px; }
.peng { margin: 2px 0 0; } .plit, .pnote, .pbad { margin: 0; } .pbad { color: var(--err); }
.pbtns { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 6px; }
.rgrid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px 24px; margin: 8px 0 14px; }
.rgrid h4 { font-size: 15px; color: var(--soft); }
.rgrid ul { margin: 0; padding-left: 18px; }
.warnlist li::marker { color: var(--warn); }
.claimp { margin: 0; }
.cmpwrap { overflow-x: auto; margin-bottom: 12px; }
.cmp { border-collapse: collapse; width: 100%; font-size: 14px; }
.cmp th { text-align: left; font-size: 12px; color: var(--muted); font-weight: 600; padding: 4px 8px; border-bottom: 1px solid var(--line); }
.cmp td { padding: 6px 8px; border-bottom: 1px solid var(--line); vertical-align: top; }
.cmp td.phan { font-size: 20px; width: 44px; }
.cmp tr.iss-tone td, .cmp tr.iss-spelling td, .cmp tr.iss-missing td, .cmp tr.iss-extra td { background: var(--errbg); }
.cmp tr.iss-tone td { background: var(--warnbg); }
.iss { display: inline-block; margin-left: 8px; font: 11px var(--mono); text-transform: uppercase; color: var(--err); }
.inote { display: block; }
.drills { list-style: none; padding: 0 !important; display: grid; gap: 6px; }
.drill { display: flex; flex-wrap: wrap; align-items: center; gap: 6px; }
.recon { background: var(--card); border: 1px solid var(--line); border-radius: 16px; padding: 14px 16px; margin: 12px 0; }
.recon ul { list-style: none; padding: 0; margin: 0 0 6px; display: grid; gap: 6px; }

/* notebook */
.history { list-style: none; padding: 0; margin: 12px 0 0; display: grid; gap: 8px; }
.hrow { display: flex; align-items: center; gap: 12px; background: var(--card); border: 1px solid var(--line); border-radius: 14px; padding: 10px 12px; }
.hglyph { font: 22px var(--han); width: 40px; height: 40px; display: grid; place-items: center; background: var(--accent-soft); color: var(--accent); border-radius: 10px; flex: none; }
.hinfo { flex: 1; display: flex; flex-direction: column; min-width: 0; }
.hinfo b { display: block; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.hinfo span { overflow-wrap: anywhere; }

.toasts { position: fixed; right: 16px; bottom: 16px; display: grid; gap: 8px; z-index: 50; max-width: min(420px, calc(100vw - 32px)); }
.toast { background: var(--ink); color: var(--bg); padding: 10px 14px; border-radius: 12px; font-size: 14px; box-shadow: 0 6px 22px rgba(0,0,0,.18); transition: opacity .5s; }
.toast.err { background: var(--err); color: #fff; }
.toast a { color: inherit; font-weight: 700; }
.toast.gone { opacity: 0; }
.foot { max-width: 1100px; margin: 0 auto; padding: 22px 22px 40px; border-top: 1px solid var(--line); color: var(--muted); font-size: 13px; }

/* docs pages */
.doc { max-width: 880px; margin: 0 auto; padding: 28px 20px 40px; }
.doc h1 { font-size: 30px; } .doc h2 { margin-top: 34px; }
.doc pre { background: var(--card2); border: 1px solid var(--line); border-radius: 10px; padding: 12px; overflow-x: auto; font-size: 12.5px; }
.doc code { font-family: var(--mono); font-size: .92em; }
.doc table { border-collapse: collapse; width: 100%; display: block; overflow-x: auto; font-size: 14px; margin: 10px 0; }
.doc th, .doc td { border: 1px solid var(--line); padding: 6px 8px; text-align: left; vertical-align: top; }
.codegroup { margin: 12px 0; }
.tabs { display: flex; flex-wrap: wrap; gap: 4px; margin-bottom: 6px; }
.tab { border: 1px solid var(--line2); background: var(--card); border-radius: 6px; padding: 4px 10px; cursor: pointer; font-size: 13px; }
.tab.active { background: var(--ink); color: var(--bg); border-color: var(--ink); }
.statebox { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 12px 14px; margin: 14px 0; }
.tokenrow { display: flex; flex-wrap: wrap; gap: 8px; margin: 8px 0; }
.tokenbox { font-family: var(--mono); background: var(--card2); border: 1px solid var(--line); border-radius: 10px; padding: 10px; overflow-wrap: anywhere; width: 100%; }

@media (max-width: 860px) {
  .hero { grid-template-columns: 1fr; }
  .voicerow { grid-column: 1; }
}
@media (max-width: 640px) {
  .bar { padding: 8px 12px; gap: 8px; flex-wrap: wrap; }
  .back { display: none; }
  .hero { padding: 24px 16px 10px; }
  .hero h1 { font-size: 30px; }
  .wrap { padding: 0 16px 32px; }
  .tonepad { gap: 5px; }
  .tbtn { padding: 12px 2px 9px; border-radius: 14px; }
  .tbtn .tmark { font-size: 23px; }
  .tbtn .tname { font-size: 10.5px; }
  .panel, .askform, .result { padding: 14px; border-radius: 14px; }
  .row2, .row3, .lanes, .rgrid { grid-template-columns: 1fr; }
  .row3 { grid-template-columns: 1fr 1fr 1fr; gap: 6px; }
  .grid { grid-template-columns: 30px repeat(5, minmax(0, 1fr)); gap: 3px; }
  .gcell { padding: 6px 1px 4px; min-height: 64px; border-radius: 9px; }
  .gword { font-size: 15px; min-height: 20px; }
  .gpy { font-size: 10px; }
  .ghead { font-size: 10px; }
  .phrases { grid-template-columns: 1fr; }
  .rhead { flex-direction: column; gap: 8px; }
  .score { margin-left: 0; width: 100%; }
  .hrow { flex-wrap: wrap; }
  .hinfo { flex-basis: calc(100% - 56px); }
}
.fixrow { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 12px; }
.fixlist { margin: 4px 0 0; padding-left: 18px; } .fixlist li { margin: 2px 0; }
.fixlist .iss-tone, .fixlist .iss-missing { color: var(--warn); } .fixlist .iss-spelling, .fixlist .iss-extra { color: var(--err); }
.drill .pbtns { margin-top: 0; }