:root {
  --bg: #061018;
  --bg-2: #091722;
  --panel: rgba(12, 28, 40, .82);
  --panel-2: rgba(17, 37, 51, .72);
  --line: rgba(149, 204, 222, .17);
  --line-strong: rgba(149, 204, 222, .34);
  --text: #edf8fa;
  --muted: #94aeb7;
  --cyan: #5de2df;
  --cyan-soft: rgba(93, 226, 223, .12);
  --gold: #f0c36b;
  --success: #7ee3a1;
  --danger: #ff8d91;
  --radius: 18px;
  --shadow: 0 30px 80px rgba(0, 0, 0, .28);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  min-width: 320px;
  color: var(--text);
  background:
    radial-gradient(circle at 18% 0%, rgba(34, 109, 130, .23), transparent 34rem),
    radial-gradient(circle at 88% 38%, rgba(16, 78, 96, .18), transparent 32rem),
    linear-gradient(180deg, #061018 0%, #07131d 55%, #050c12 100%);
  font-family: Inter, Avenir, "Segoe UI", system-ui, sans-serif;
  line-height: 1.55;
}
button, input { font: inherit; }
button { color: inherit; }
.noise {
  position: fixed; inset: 0; pointer-events: none; opacity: .035; z-index: 20;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 180 180' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.95' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='.8'/%3E%3C/svg%3E");
}
.shell { width: min(1180px, calc(100% - 40px)); margin: 0 auto; }
.site-header {
  position: sticky; top: 0; z-index: 15;
  min-height: 78px; padding: 12px 28px;
  display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; gap: 24px;
  background: rgba(5, 14, 21, .84); border-bottom: 1px solid var(--line); backdrop-filter: blur(18px);
}
.brand { display: inline-flex; align-items: center; gap: 12px; color: inherit; text-decoration: none; width: max-content; }
.brand-mark { font-size: 28px; filter: drop-shadow(0 0 15px rgba(93,226,223,.4)); }
.brand strong { display: block; letter-spacing: .18em; font-size: 15px; }
.brand small { display: block; color: var(--muted); font-size: 10px; letter-spacing: .11em; text-transform: uppercase; }
.main-nav { display: flex; padding: 5px; border: 1px solid var(--line); border-radius: 999px; background: rgba(255,255,255,.025); }
.nav-button { border: 0; background: transparent; padding: 9px 16px; border-radius: 999px; color: var(--muted); cursor: pointer; font-size: 13px; font-weight: 700; }
.nav-button:hover, .nav-button.active { color: var(--text); background: var(--cyan-soft); }
.header-stats { justify-self: end; display: flex; gap: 16px; color: var(--muted); font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace; font-size: 11px; text-transform: uppercase; }
.header-stats strong { color: var(--text); }
.page-section { display: none; }
.page-section.active { display: block; animation: pageIn .35s ease both; }
@keyframes pageIn { from { opacity: 0; transform: translateY(5px); } }
.hero { padding: 94px 0 72px; }
.eyebrow { margin: 0 0 12px; color: var(--cyan); font: 500 11px/1.2 "SFMono-Regular", Consolas, "Liberation Mono", monospace; letter-spacing: .17em; text-transform: uppercase; }
h1, h2, h3, p { text-wrap: pretty; }
h1 { margin: 0; max-width: 900px; font-size: clamp(45px, 7vw, 88px); line-height: .98; letter-spacing: -.055em; }
h1 em { color: var(--cyan); font-style: normal; }
.hero-copy, .lead { max-width: 820px; color: #b2c8cf; font-size: clamp(17px, 2vw, 20px); }
.hero-copy { margin: 28px 0 42px; }
.demo-grid { display: grid; grid-template-columns: .88fr 1.12fr; gap: 18px; }
.slip-card, .readout-card, .game-panel, .method-card, .vocabulary-note {
  border: 1px solid var(--line); border-radius: var(--radius); background: var(--panel); box-shadow: var(--shadow); overflow: hidden;
}
.slip-card { position: relative; padding: 31px; background: linear-gradient(145deg, rgba(235,245,239,.97), rgba(199,219,214,.93)); color: #112027; transform: rotate(-.5deg); }
.slip-card::before { content: ""; position: absolute; inset: 0; opacity: .26; background-image: repeating-linear-gradient(0deg, transparent 0 29px, rgba(20,60,70,.12) 30px); }
.slip-card > * { position: relative; }
.card-kicker, .readout-head, .game-topline { font: 500 10px/1.2 "SFMono-Regular", Consolas, "Liberation Mono", monospace; letter-spacing: .13em; text-transform: uppercase; }
.word-list { list-style: none; padding: 14px 0 7px; margin: 0; font: 500 clamp(28px, 4vw, 47px)/1.24 "SFMono-Regular", Consolas, "Liberation Mono", monospace; }
.word-list li::before { content: "•"; margin-right: 14px; color: #2e7178; }
.microcopy { margin: 16px 0 0; color: #536970; font-size: 12px; }
.readout-card { padding: 31px; min-height: 310px; display: flex; flex-direction: column; }
.readout-head, .game-topline { display: flex; justify-content: space-between; gap: 16px; color: var(--muted); }
.master-label { margin-top: auto; color: var(--muted); font: 500 11px "SFMono-Regular", Consolas, "Liberation Mono", monospace; letter-spacing: .18em; text-align: center; }
.master-word { min-height: 82px; display: grid; place-items: center; font-size: clamp(45px, 7vw, 78px); font-weight: 800; letter-spacing: .08em; color: var(--cyan); text-transform: uppercase; text-shadow: 0 0 35px rgba(93,226,223,.22); }
.master-word.reveal { animation: reveal .65s cubic-bezier(.2,.8,.2,1) both; }
@keyframes reveal { 0% { filter: blur(14px); opacity: 0; letter-spacing: .45em; } 100% { filter: blur(0); opacity: 1; } }
.demo-actions { display: flex; gap: 9px; justify-content: center; }
.button { border: 1px solid transparent; border-radius: 11px; padding: 12px 18px; cursor: pointer; font-weight: 800; font-size: 13px; transition: .18s ease; }
.button:hover { transform: translateY(-1px); }
.button.primary { color: #061117; background: var(--cyan); box-shadow: 0 8px 28px rgba(93,226,223,.17); }
.button.secondary { background: rgba(255,255,255,.055); border-color: var(--line-strong); }
.button.ghost { background: transparent; color: var(--muted); border-color: var(--line); }
.drill-area { padding: 20px 0 96px; }
.section-heading { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; align-items: end; margin-bottom: 27px; }
.section-heading h2 { margin: 0; font-size: clamp(32px, 4vw, 50px); letter-spacing: -.04em; }
.section-heading > p { margin: 0; color: var(--muted); }
.section-heading.compact { align-items: center; }
.difficulty-row { display: grid; grid-template-columns: repeat(3, 1fr) auto; gap: 8px; margin-bottom: 12px; }
.difficulty { text-align: left; cursor: pointer; border: 1px solid var(--line); border-radius: 12px; background: rgba(255,255,255,.025); padding: 12px 14px; }
.difficulty strong, .difficulty span { display: block; }
.difficulty strong { font-size: 13px; }
.difficulty span { color: var(--muted); font-size: 10px; }
.difficulty.active { border-color: rgba(93,226,223,.55); background: var(--cyan-soft); }
.timer { min-width: 105px; display: grid; place-items: center; border: 1px solid var(--line); border-radius: 12px; color: var(--muted); font: 500 12px "SFMono-Regular", Consolas, "Liberation Mono", monospace; }
.game-panel { padding: 25px; }
.game-topline { padding-bottom: 20px; border-bottom: 1px solid var(--line); }
#round-score { color: var(--gold); }
.drill-words { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; margin: 24px 0; }
.drill-word { min-height: 130px; display: grid; place-items: center; padding: 16px; border: 1px solid var(--line); border-radius: 14px; background: linear-gradient(145deg, rgba(255,255,255,.052), rgba(255,255,255,.018)); font: 500 clamp(22px, 3vw, 37px) "SFMono-Regular", Consolas, "Liberation Mono", monospace; text-align: center; overflow-wrap: anywhere; }
.answer-row { display: grid; grid-template-columns: 1fr auto auto; gap: 10px; }
input { width: 100%; min-width: 0; border: 1px solid var(--line-strong); border-radius: 11px; padding: 14px 16px; color: var(--text); background: rgba(0,0,0,.18); outline: none; }
input:focus { border-color: var(--cyan); box-shadow: 0 0 0 3px rgba(93,226,223,.09); }
input::placeholder { color: #68808a; }
.hidden { display: none !important; }
.feedback { min-height: 38px; padding: 10px 2px 0; font-size: 14px; font-weight: 700; }
.feedback.success { color: var(--success); }
.feedback.error { color: var(--danger); }
.hint-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 8px; margin: 13px 0 18px; }
.hint { border: 1px solid var(--line); border-radius: 11px; background: rgba(255,255,255,.02); padding: 11px; color: var(--muted); cursor: pointer; font-size: 11px; text-align: left; }
.hint span { display: block; color: var(--cyan); font: 500 9px "SFMono-Regular", Consolas, "Liberation Mono", monospace; letter-spacing: .12em; }
.hint b { float: right; color: var(--gold); }
.hint:hover:not(:disabled) { border-color: var(--line-strong); color: var(--text); }
.hint:disabled { opacity: .38; cursor: not-allowed; }
.deduction-grid { display: grid; grid-template-columns: .8fr .7fr 1.5fr; gap: 9px; }
.deduction-box { min-height: 105px; padding: 15px; border: 1px solid var(--line); border-radius: 12px; background: rgba(0,0,0,.13); }
.deduction-box > span { display: block; color: var(--muted); font: 500 9px "SFMono-Regular", Consolas, "Liberation Mono", monospace; letter-spacing: .12em; }
.deduction-box strong { display: block; margin-top: 7px; font: 500 22px "SFMono-Regular", Consolas, "Liberation Mono", monospace; color: var(--cyan); }
.deduction-box small { color: var(--muted); }
.candidate-list { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 9px; }
.candidate-chip { border: 1px solid var(--line-strong); border-radius: 999px; padding: 5px 9px; color: #c7d9de; font-size: 11px; }
.session-stats { display: grid; grid-template-columns: repeat(4, 1fr) auto; gap: 10px; align-items: stretch; margin-top: 12px; }
.session-stats > div { padding: 14px; border: 1px solid var(--line); border-radius: 11px; background: rgba(255,255,255,.02); }
.session-stats span, .session-stats strong { display: block; }
.session-stats span { color: var(--muted); font-size: 10px; }
.session-stats strong { font: 500 21px "SFMono-Regular", Consolas, "Liberation Mono", monospace; }
.text-button { border: 0; background: transparent; color: var(--muted); cursor: pointer; font-size: 11px; }
.text-button:hover { color: var(--danger); }
.content-shell { padding: 90px 0 110px; }
.content-shell > h1 { font-size: clamp(44px, 7vw, 79px); }
.lead { margin: 25px 0 45px; }
.prong-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; margin-bottom: 22px; }
.prong-grid article { padding: 24px; border-top: 2px solid var(--cyan); background: rgba(255,255,255,.025); }
.prong-grid article > span { color: rgba(93,226,223,.36); font: 500 42px "SFMono-Regular", Consolas, "Liberation Mono", monospace; }
.prong-grid h3 { margin: 6px 0; font-size: 20px; }
.prong-grid b { color: var(--cyan); font: 500 9px "SFMono-Regular", Consolas, "Liberation Mono", monospace; letter-spacing: .12em; }
.prong-grid p { color: var(--muted); font-size: 14px; }
.method-card { padding: 27px; margin-top: 14px; }
.scan-table { border: 1px solid var(--line); border-radius: 12px; overflow: hidden; }
.scan-row { display: grid; grid-template-columns: .6fr .8fr 2fr; gap: 15px; padding: 14px 16px; border-top: 1px solid var(--line); align-items: center; }
.scan-row:first-child { border-top: 0; }
.scan-row.head { color: var(--muted); background: rgba(255,255,255,.035); font: 500 10px "SFMono-Regular", Consolas, "Liberation Mono", monospace; text-transform: uppercase; }
.scan-row code { color: var(--cyan); }
.method-columns { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.method-card h2 { margin: 0 0 12px; }
.method-card ul { padding-left: 20px; color: var(--muted); }
.method-card li { margin: 9px 0; }
.ethics-note { display: flex; gap: 18px; margin-top: 22px; padding: 19px; border-left: 3px solid var(--gold); background: rgba(240,195,107,.06); }
.ethics-note strong { color: var(--gold); }
.ethics-note p { margin: 0; color: var(--muted); }
.solver-shell { min-height: calc(100vh - 150px); }
.solver-form { display: grid; grid-template-columns: repeat(3, 1fr) auto; gap: 10px; align-items: end; padding: 22px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--panel); }
.solver-form label span { display: block; margin-bottom: 7px; color: var(--muted); font: 500 9px "SFMono-Regular", Consolas, "Liberation Mono", monospace; letter-spacing: .12em; }
.solver-summary { margin: 18px 0 9px; padding: 15px 18px; border: 1px solid var(--line); border-radius: 12px; color: var(--muted); background: rgba(255,255,255,.025); }
.solver-results { display: grid; gap: 9px; }
.solution-card { display: grid; grid-template-columns: 70px 1fr auto; gap: 18px; align-items: center; padding: 18px; border: 1px solid var(--line); border-radius: 13px; background: var(--panel-2); }
.solution-rank { color: rgba(93,226,223,.45); font: 500 30px "SFMono-Regular", Consolas, "Liberation Mono", monospace; }
.solution-word { margin: 0; font-size: 26px; text-transform: uppercase; }
.solution-detail { color: var(--muted); font-size: 12px; }
.solution-score { color: var(--gold); font: 500 12px "SFMono-Regular", Consolas, "Liberation Mono", monospace; }
.empty-result { padding: 28px; text-align: center; border: 1px dashed var(--line-strong); border-radius: 13px; color: var(--muted); }
.vocabulary-note { margin-top: 20px; padding: 21px; }
.vocabulary-note h3 { margin: 0 0 5px; }
.vocabulary-note p { margin: 0; color: var(--muted); }
code { font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace; }
footer { display: flex; justify-content: space-between; gap: 20px; padding: 24px 30px; border-top: 1px solid var(--line); color: var(--muted); font-size: 10px; text-transform: uppercase; letter-spacing: .08em; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0; }

@media (max-width: 900px) {
  .site-header { grid-template-columns: 1fr auto; }
  .main-nav { grid-row: 2; grid-column: 1 / -1; justify-self: center; }
  .header-stats { font-size: 9px; }
  .demo-grid, .section-heading, .method-columns { grid-template-columns: 1fr; }
  .difficulty-row { grid-template-columns: repeat(3, 1fr); }
  .timer { grid-column: 1 / -1; min-height: 44px; }
  .session-stats { grid-template-columns: repeat(2, 1fr); }
  .text-button { grid-column: 1 / -1; padding: 12px; }
  .prong-grid { grid-template-columns: 1fr; }
  .solver-form { grid-template-columns: 1fr; }
}

@media (max-width: 640px) {
  .shell { width: min(100% - 24px, 1180px); }
  .site-header { padding: 10px 12px; gap: 8px; }
  .brand small { display: none; }
  .header-stats { display: block; text-align: right; }
  .header-stats span { display: block; }
  .main-nav { width: 100%; }
  .nav-button { flex: 1; padding: 8px 5px; font-size: 11px; }
  .hero { padding: 60px 0 50px; }
  h1 { font-size: clamp(41px, 14vw, 65px); }
  .hero-copy { font-size: 16px; }
  .demo-grid { gap: 12px; }
  .slip-card, .readout-card, .game-panel { padding: 19px; }
  .demo-actions { flex-direction: column; }
  .difficulty-row { grid-template-columns: 1fr; }
  .timer { grid-column: auto; }
  .drill-words { grid-template-columns: 1fr; }
  .drill-word { min-height: 83px; }
  .answer-row { grid-template-columns: 1fr; }
  .hint-grid, .deduction-grid { grid-template-columns: 1fr; }
  .session-stats { grid-template-columns: 1fr 1fr; }
  .content-shell { padding: 58px 0 75px; }
  .method-card { padding: 19px; }
  .scan-row { grid-template-columns: 1fr; gap: 4px; }
  .scan-row.head { display: none; }
  .solution-card { grid-template-columns: 45px 1fr; }
  .solution-score { grid-column: 2; }
  footer { flex-direction: column; }
}