/* ============================================================================
   Tau Square Academy — public site design system (pairs with styles.css).

   Bands set the tone. Every component reads the tone's variables (--fg,
   --body, --muted, --line, --card, --accent), so any component works on
   any band: ink (navy, the brand) or paper (ivory, for reading).

   Readability rules this file enforces:
   - body text 17px, weight 400, line-height 1.65, lines kept under ~68ch;
   - every text colour passes WCAG AA on its band (body text passes AAA);
   - one gold button per screen: gold means "the next step".

   Every band is navy by default; html[data-look="paper"] makes the reading
   bands ivory instead.
   ========================================================================== */

:root {
    --ink-950: #03070C;
    --ink-900: #070B14;
    --ink-850: #0B1220;
    --ink-800: #111A2C;
    --paper: #F6F1E7;
    --paper-2: #EEE7D9;
    --paper-card: #FFFCF6;
    --gold: #C8A96B;
    --gold-hi: #D9BE85;
    --gold-ink: #7A5B22;

    --serif: 'Playfair Display', Georgia, 'Times New Roman', serif;
    --sans: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
    --mono: 'JetBrains Mono', ui-monospace, Consolas, monospace;

    --wrap: 1180px;
    --gutter: 20px;
    --read: 68ch;
    --nav-h: 72px;
}
@media (min-width: 768px) { :root { --gutter: 32px; } }

/* ── Tones ─────────────────────────────────────────────────────────────── */
.site, .tone-ink {
    --bg: var(--ink-950);
    --fg: #F5F6F8;
    --body: #C9D0DB;
    --muted: #9AA3B2;
    --line: rgba(255, 255, 255, .12);
    --line-strong: rgba(255, 255, 255, .28);
    --card: var(--ink-900);
    --card-line: rgba(255, 255, 255, .10);
    --accent: var(--gold);
    --chip: rgba(255, 255, 255, .06);
}
.tone-ink-2 {
    --bg: var(--ink-900);
    --fg: #F5F6F8;
    --body: #C9D0DB;
    --muted: #9AA3B2;
    --line: rgba(255, 255, 255, .12);
    --line-strong: rgba(255, 255, 255, .28);
    --card: var(--ink-850);
    --card-line: rgba(255, 255, 255, .10);
    --accent: var(--gold);
    --chip: rgba(255, 255, 255, .06);
}
/* Navy everywhere by default: the brand, and the owner's choice (2026-10-26).
   The "paper" bands are the reading sections; html[data-look="paper"] turns
   them ivory if that's ever wanted again. */
.tone-paper, .tone-paper-2 {
    --bg: var(--ink-950);
    --fg: #F5F6F8;
    --body: #C9D0DB;
    --muted: #9AA3B2;
    --line: rgba(255, 255, 255, .12);
    --line-strong: rgba(255, 255, 255, .28);
    --card: var(--ink-900);
    --card-line: rgba(255, 255, 255, .10);
    --accent: var(--gold);
    --chip: rgba(255, 255, 255, .06);
}
.tone-paper-2 { --bg: var(--ink-900); --card: var(--ink-850); }

html[data-look="paper"] .tone-paper,
html[data-look="paper"] .tone-paper-2 {
    --bg: var(--paper);
    --fg: #10151F;
    --body: #2D3341;
    --muted: #5A6170;
    --line: rgba(16, 21, 31, .14);
    --line-strong: rgba(16, 21, 31, .32);
    --card: var(--paper-card);
    --card-line: rgba(16, 21, 31, .10);
    --accent: var(--gold-ink);
    --chip: rgba(16, 21, 31, .05);
}
html[data-look="paper"] .tone-paper-2 { --bg: var(--paper-2); --card: #FBF7EF; }

/* ── Base ──────────────────────────────────────────────────────────────── */
.site {
    margin: 0;
    background: var(--ink-950);
    color: var(--body);
    font: 400 17px/1.65 var(--sans);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
}
@media (max-width: 380px) { .site { font-size: 16px; } }
.site img { max-width: 100%; height: auto; }
.site ::selection { background: rgba(200, 169, 107, .35); }

.band {
    background: var(--bg);
    color: var(--body);
    padding: clamp(64px, 9vw, 112px) 0;
    position: relative;
}
.band-tight { padding: clamp(40px, 5vw, 64px) 0; }
.band + .band { border-top: 1px solid rgba(255, 255, 255, .06); }
.band-first { padding-top: calc(var(--nav-h) + clamp(48px, 8vw, 96px)); }
.wrap { max-width: var(--wrap); margin: 0 auto; padding: 0 var(--gutter); }
.wrap-read { max-width: calc(760px + 2 * var(--gutter)); margin: 0 auto; padding: 0 var(--gutter); }

/* ── Type ──────────────────────────────────────────────────────────────── */
.h1, .h2, .h3, .h4 { color: var(--fg); font-variant-numeric: lining-nums; margin: 0; }
.h1 {
    font: 400 clamp(2.3rem, 1.3rem + 3.3vw, 3.9rem)/1.08 var(--serif);
    letter-spacing: -.015em;
}
.h2 {
    font: 400 clamp(1.95rem, 1.4rem + 2.1vw, 3rem)/1.12 var(--serif);
    letter-spacing: -.01em;
}
.h3 { font: 500 clamp(1.3rem, 1.15rem + .5vw, 1.6rem)/1.25 var(--serif); }
.h4 { font: 600 1.08rem/1.35 var(--sans); }
.h1 em, .h2 em, .h3 em { font-style: italic; color: var(--accent); }
.h1 .dim, .h2 .dim { color: var(--muted); }

.eyebrow {
    display: block;
    font: 500 12.5px/1.3 var(--mono);
    letter-spacing: .14em;
    text-transform: uppercase;
    color: var(--accent);
    margin: 0 0 16px;
}
.lead {
    font-size: clamp(1.08rem, 1rem + .35vw, 1.28rem);
    line-height: 1.6;
    color: var(--body);
    max-width: 62ch;
    margin: 20px 0 0;
}
:where(.site) p { margin: 0; }
:where(.site) p + p { margin-top: 1em; }
.muted { color: var(--muted); }
.small { font-size: .92rem; line-height: 1.55; }
.fine { font-size: .84rem; line-height: 1.5; color: var(--muted); }
.strong, .site b, .site strong { color: var(--fg); font-weight: 600; }
.center { text-align: center; }
.center .lead, .center .sec-sub { margin-left: auto; margin-right: auto; }

.prose { max-width: var(--read); }
.prose p, .prose ul, .prose ol { margin: 0 0 1.05em; }
.prose a, .tlink {
    color: var(--fg);
    text-decoration: underline;
    text-decoration-color: var(--accent);
    text-decoration-thickness: 1.5px;
    text-underline-offset: 3px;
}
.prose a:hover, .tlink:hover { color: var(--accent); }

/* Section head: eyebrow, heading, one line of context. */
.sec-head { max-width: 780px; margin: 0 0 clamp(36px, 5vw, 56px); }
.sec-head.center { margin-left: auto; margin-right: auto; }
.sec-sub { color: var(--body); font-size: 1.08rem; line-height: 1.6; max-width: 62ch; margin-top: 16px; }

/* ── Buttons and links ─────────────────────────────────────────────────── */
.btn {
    display: inline-flex; align-items: center; justify-content: center; gap: .55em;
    min-height: 52px; padding: 0 26px;
    font: 600 15.5px/1.1 var(--sans); letter-spacing: .005em;
    text-decoration: none; text-align: center;
    border: 1px solid transparent; border-radius: 2px;
    cursor: pointer;
    transition: background-color .18s, border-color .18s, color .18s, transform .18s;
}
.btn:active { transform: translateY(1px); }
.btn-primary { background: var(--gold); color: var(--ink-950); }
.btn-primary:hover { background: var(--gold-hi); }
.btn-ghost { background: transparent; color: var(--fg); border-color: var(--line-strong); }
.btn-ghost:hover { border-color: var(--fg); }
.btn-light { background: #fff; color: var(--ink-950); }
.btn-light:hover { background: #E9ECF1; }
.btn-sm { min-height: 42px; padding: 0 16px; font-size: 14.5px; }
.btn-block { display: flex; width: 100%; }
.btn-row { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 32px; }
.center .btn-row { justify-content: center; }
@media (max-width: 520px) { .btn-row .btn { flex: 1 1 100%; } }
.btn-note { margin-top: 14px; font-size: .9rem; color: var(--muted); }

.more {
    display: inline-flex; align-items: center; gap: .45em;
    font-weight: 600; color: var(--fg); text-decoration: none;
    border-bottom: 1.5px solid var(--accent);
    padding-bottom: 2px;
}
.more::after { content: '→'; transition: transform .18s; }
.more:hover::after { transform: translateX(3px); }
.more-row { margin-top: 36px; }

/* ── Grids ─────────────────────────────────────────────────────────────── */
.g2, .g3, .g4 { display: grid; gap: 20px; grid-template-columns: 1fr; }
@media (min-width: 720px) { .g2, .g4 { grid-template-columns: repeat(2, minmax(0, 1fr)); } .g3 { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (min-width: 1000px) { .g3 { grid-template-columns: repeat(3, minmax(0, 1fr)); } .g4 { grid-template-columns: repeat(4, minmax(0, 1fr)); } }
.gap-lg { gap: 28px; }

.split { display: grid; gap: clamp(36px, 6vw, 72px); grid-template-columns: 1fr; align-items: center; }
@media (min-width: 960px) {
    .split { grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr); }
    .split.flip > :first-child { order: 2; }
    .split.top { align-items: start; }
    .split.hero { grid-template-columns: minmax(0, .92fr) minmax(0, 1.08fr); }
}

/* ── Cards ─────────────────────────────────────────────────────────────── */
.card {
    background: var(--card);
    border: 1px solid var(--card-line);
    padding: clamp(24px, 3vw, 32px);
}
.card .h3, .card .h4 { margin-bottom: 10px; }
.card-gold { border-color: rgba(200, 169, 107, .55); }
.card p { color: var(--body); }

/* Numbered steps (How it works in three steps). */
.step-n {
    display: inline-flex; align-items: center; justify-content: center;
    width: 40px; height: 40px; margin-bottom: 18px;
    border: 1px solid var(--accent); color: var(--accent);
    font: 500 15px/1 var(--mono);
}

/* Bulleted lists with a mark. */
.ticks, .crosses { list-style: none; margin: 0; padding: 0; display: grid; gap: 14px; }
.ticks li, .crosses li { position: relative; padding-left: 34px; }
.ticks li::before, .crosses li::before {
    position: absolute; left: 0; top: .1em;
    width: 22px; height: 22px; display: grid; place-items: center;
    font: 700 13px/1 var(--sans); border-radius: 50%;
}
.ticks li::before { content: '✓'; color: var(--ink-950); background: var(--gold); }
.crosses li::before { content: '✕'; color: var(--muted); border: 1px solid var(--line-strong); }

.dash { list-style: none; margin: 0; padding: 0; }
.dash li { padding: 14px 0; border-top: 1px solid var(--line); }
.dash li:last-child { border-bottom: 1px solid var(--line); }

/* ── Header ────────────────────────────────────────────────────────────── */
.site-header { position: fixed; inset: 0 0 auto 0; z-index: 50; }
.site-nav {
    background: rgba(3, 7, 12, .92);
    backdrop-filter: saturate(140%) blur(12px);
    -webkit-backdrop-filter: saturate(140%) blur(12px);
    border-bottom: 1px solid rgba(255, 255, 255, .07);
}
.nav-row { height: var(--nav-h); display: flex; align-items: center; justify-content: space-between; gap: 16px; }
.brand { display: inline-flex; align-items: center; gap: 10px; color: #fff; text-decoration: none; flex: none; }
.brand img { width: 30px; height: 30px; }
.brand-name { font: 400 17px/1 var(--serif); letter-spacing: .14em; text-transform: uppercase; }
.brand-name i { color: var(--gold); font-size: 13px; letter-spacing: .04em; text-transform: lowercase; margin-left: 4px; }
@media (max-width: 400px) { .brand-name i { display: none; } }
.nav-links { display: none; list-style: none; margin: 0; padding: 0; gap: 26px; }
.nav-links a, .nav-signin {
    color: #C3CAD6; text-decoration: none; font: 500 15px/1 var(--sans);
    padding: 10px 0; transition: color .15s;
}
.nav-links a:hover, .nav-signin:hover { color: #fff; }
.nav-links a[aria-current="page"] {
    color: #fff;
    text-decoration: underline; text-decoration-color: var(--gold);
    text-decoration-thickness: 2px; text-underline-offset: 9px;
}
.nav-actions { display: flex; align-items: center; gap: 18px; }
.nav-signin { display: none; }
.menu-btn {
    display: inline-flex; align-items: center; justify-content: center;
    width: 44px; height: 44px; color: #fff; background: transparent;
    border: 1px solid rgba(255, 255, 255, .22); cursor: pointer;
}
.menu-btn svg { width: 20px; height: 20px; }
@media (min-width: 640px) { .nav-signin { display: inline-block; } }
@media (min-width: 1100px) {
    .nav-links { display: flex; }
    .menu-btn { display: none; }
}
.mobile-menu { border-top: 1px solid rgba(255, 255, 255, .07); background: var(--ink-950); max-height: calc(100vh - var(--nav-h)); overflow-y: auto; }
.mobile-menu ul { list-style: none; margin: 0; padding: 8px var(--gutter) 4px; }
.mobile-menu li a {
    display: block; padding: 15px 2px; color: #E3E7ED; text-decoration: none;
    font: 500 17px/1.2 var(--sans); border-bottom: 1px solid rgba(255, 255, 255, .07);
}
.mobile-menu li a[aria-current="page"] { color: var(--gold); }
.mobile-menu .mm-foot { padding: 16px var(--gutter) 24px; display: grid; gap: 10px; }
@media (min-width: 1100px) { .mobile-menu { display: none !important; } }

/* ── Footer ────────────────────────────────────────────────────────────── */
.site-footer { background: var(--ink-950); border-top: 1px solid rgba(255, 255, 255, .08); color: #AEB6C3; padding: 64px 0 calc(40px + env(safe-area-inset-bottom)); }
.foot-grid { display: grid; gap: 40px; grid-template-columns: repeat(2, minmax(0, 1fr)); }
.foot-brand { grid-column: 1 / -1; }
.foot-brand p { margin-top: 14px; max-width: 34ch; font-size: .95rem; line-height: 1.6; }
@media (min-width: 900px) { .foot-grid { grid-template-columns: 1.4fr 1fr 1fr 1fr; } .foot-brand { grid-column: auto; } }
.foot-h { font: 500 12px/1.3 var(--mono); letter-spacing: .14em; text-transform: uppercase; color: var(--gold); margin: 0 0 14px; }
.foot-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 4px; }
.foot-list a { display: inline-block; padding: 6px 0; color: #C3CAD6; text-decoration: none; font-size: .97rem; }
.foot-list a:hover { color: #fff; }
.foot-legal {
    margin-top: 48px; padding-top: 24px; border-top: 1px solid rgba(255, 255, 255, .08);
    display: grid; gap: 14px; font-size: .84rem; line-height: 1.6; color: #9AA3B2;
}
.foot-legal a { color: inherit; }
@media (min-width: 900px) { .foot-legal { grid-template-columns: 1fr 1fr; } .foot-legal p:last-child { text-align: right; } }

/* WhatsApp button and the phone's bottom action bar. */
.wa-fab {
    position: fixed; right: 18px; bottom: 22px; z-index: 40;
    display: flex; align-items: center; gap: 10px;
    background: var(--ink-900); color: var(--gold);
    border: 1px solid rgba(200, 169, 107, .45); border-radius: 999px;
    padding: 12px 18px; text-decoration: none;
    font: 500 12px/1 var(--mono); letter-spacing: .12em; text-transform: uppercase;
    box-shadow: 0 10px 30px rgba(0, 0, 0, .45);
    transition: border-color .2s, transform .2s, bottom .25s;
}
.wa-fab:hover { border-color: var(--gold); transform: translateY(-2px); }
.wa-fab svg { width: 18px; height: 18px; flex: none; }
@media (max-width: 767px) { .wa-fab { padding: 13px; } .wa-fab span { display: none; } }

.m-cta {
    position: fixed; left: 0; right: 0; bottom: 0; z-index: 45;
    display: flex; align-items: center; justify-content: space-between; gap: 12px;
    padding: 12px var(--gutter) calc(12px + env(safe-area-inset-bottom));
    background: rgba(3, 7, 12, .96); border-top: 1px solid rgba(255, 255, 255, .1);
    transform: translateY(110%); transition: transform .28s ease;
}
.m-cta p { font-size: .9rem; line-height: 1.3; color: #C9D0DB; }
.m-cta p b { color: #fff; display: block; }
.m-cta.on { transform: none; }
.m-cta.on ~ .wa-fab { bottom: 92px; }
@media (min-width: 768px) { .m-cta { display: none; } }

/* ── Page parts ────────────────────────────────────────────────────────── */

/* Hero with the book collection. */
.hero-figure { margin: 0; }
.hero-figure img { display: block; width: 100%; height: auto; }
.cap { margin-top: 12px; font-size: .84rem; line-height: 1.5; color: var(--muted); text-align: center; }

/* Conference names. */
.confs { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px 30px; margin: 0; padding: 0; list-style: none; }
.confs li { font: 600 clamp(1.15rem, 1rem + .6vw, 1.5rem)/1.2 var(--serif); color: var(--fg); opacity: .82; }
.confs-label { text-align: center; color: var(--muted); font-size: .95rem; margin-bottom: 18px; }

/* Chips: a short in-page table of contents. */
.chips { display: flex; flex-wrap: wrap; gap: 8px; list-style: none; margin: 28px 0 0; padding: 0; }
.chips a {
    display: inline-flex; align-items: center; min-height: 40px; padding: 0 14px;
    background: var(--chip); border: 1px solid var(--line); color: var(--fg);
    text-decoration: none; font-size: .93rem; font-weight: 500;
}
.chips a:hover { border-color: var(--accent); }

/* The 100-hour bar: one segment per phase, width = hours. */
.hours { margin-top: 8px; }
.hours-bar { display: flex; gap: 3px; height: 54px; }
.hours-bar > span {
    flex: var(--h) 1 0; min-width: 0;
    display: flex; align-items: center; justify-content: center;
    background: var(--c, var(--gold)); color: #fff;
    font: 500 13px/1 var(--mono);
}
.hours-legend { display: grid; gap: 0; margin-top: 18px; list-style: none; padding: 0; }
.hours-legend li { display: grid; grid-template-columns: 30px 1fr auto; gap: 12px; align-items: baseline; padding: 11px 0; border-top: 1px solid var(--line); }
.hours-legend li:last-child { border-bottom: 1px solid var(--line); }
.hours-legend .n { font: 500 13px/1 var(--mono); color: var(--accent); }
.hours-legend .t { color: var(--fg); font-weight: 500; }
.hours-legend .h { font: 500 13px/1 var(--mono); color: var(--muted); }
@media (min-width: 900px) { .hours-legend { grid-template-columns: 1fr 1fr 1fr; column-gap: 32px; } }
.hours-total { margin-top: 14px; display: flex; justify-content: space-between; font: 500 13px/1.4 var(--mono); color: var(--muted); letter-spacing: .06em; text-transform: uppercase; }

/* Phase cards (How it works). */
.phase { border-top: 2px solid var(--c, var(--accent)); padding-top: 18px; }
.phase-top { display: flex; justify-content: space-between; align-items: baseline; margin-bottom: 8px; }
.phase-n { font: 500 13px/1 var(--mono); color: var(--accent); letter-spacing: .08em; }
.phase-h { font: 500 13px/1 var(--mono); color: var(--muted); }
.phase .h4 { margin-bottom: 6px; }
.phase p { font-size: .98rem; line-height: 1.6; }

/* Product rows (textbook, course, tokens). */
.product { display: grid; gap: 28px; align-items: center; grid-template-columns: 1fr; }
@media (min-width: 760px) { .product { grid-template-columns: 220px minmax(0, 1fr); gap: 44px; } }
.product img { width: 100%; max-width: 240px; height: auto; display: block; margin: 0 auto; }
.facts { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 20px; list-style: none; padding: 0; }
.facts li { padding: 7px 12px; border: 1px solid var(--line); font-size: .9rem; color: var(--fg); background: var(--chip); }

/* Playbook tiles, grouped by stage. */
.shelf + .shelf { margin-top: 52px; }
.shelf-head { display: flex; flex-wrap: wrap; align-items: baseline; gap: 6px 16px; padding-bottom: 14px; margin-bottom: 26px; border-bottom: 1px solid var(--line); }
.shelf-head .h3 { margin: 0; }
.shelf-head span { color: var(--muted); font-size: .95rem; }
.books { display: grid; gap: 34px 26px; grid-template-columns: repeat(2, minmax(0, 1fr)); list-style: none; margin: 0; padding: 0; }
@media (min-width: 760px) { .books { grid-template-columns: repeat(3, minmax(0, 1fr)); } }
@media (min-width: 1080px) { .books { grid-template-columns: repeat(4, minmax(0, 1fr)); } }
.book img { display: block; width: 100%; max-width: 190px; height: auto; margin: 0 auto 14px; }
.book .stage { display: block; font: 500 11.5px/1.3 var(--mono); letter-spacing: .12em; text-transform: uppercase; color: var(--muted); margin-bottom: 6px; }
.book .h4 { font-size: 1.02rem; margin-bottom: 6px; }
.book p { font-size: .94rem; line-height: 1.55; color: var(--body); }
.book p b { font-weight: 600; color: var(--fg); }

/* Doubt Token counts. */
.tok-row { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 10px; }
.tok-row > div { border: 1px solid var(--line); background: var(--card); padding: 16px 10px; text-align: center; }
.tok-row .rec { border-color: var(--gold); }
.tok-n { display: block; font: 400 2.4rem/1 var(--serif); color: var(--fg); font-variant-numeric: lining-nums; }
.tok-l { display: block; margin-top: 8px; font: 500 12px/1.2 var(--mono); letter-spacing: .1em; text-transform: uppercase; color: var(--muted); }

/* Plan rows (home + what you get): who it adds, price, one link. */
.plans { display: grid; gap: 14px; }
.plan-row {
    display: grid; grid-template-columns: 1fr; gap: 6px 24px; align-items: center;
    background: var(--card); border: 1px solid var(--card-line); padding: 22px 24px;
    color: inherit; text-decoration: none; transition: border-color .18s;
}
.plan-row:hover { border-color: var(--accent); }
.plan-row.rec { border-color: rgba(200, 169, 107, .6); }
@media (min-width: 760px) { .plan-row { grid-template-columns: 200px minmax(0, 1fr) auto; } }
.plan-name { font: 400 1.45rem/1.2 var(--serif); color: var(--fg); }
.plan-name small { display: block; margin-top: 4px; font: 500 11.5px/1.2 var(--mono); letter-spacing: .12em; text-transform: uppercase; color: var(--accent); }
.plan-what { color: var(--body); font-size: .98rem; line-height: 1.55; }
.plan-price { font: 400 1.6rem/1 var(--serif); color: var(--fg); font-variant-numeric: lining-nums; white-space: nowrap; }
.plan-price small { font: 400 .8rem/1 var(--sans); color: var(--muted); margin-left: 4px; }

/* Stories and quotes. */
.story { display: grid; gap: 22px; }
.story-tag { display: inline-block; font: 500 12px/1.2 var(--mono); letter-spacing: .12em; text-transform: uppercase; color: var(--accent); }
.story-beat .h4 { color: var(--accent); font: 500 12px/1.3 var(--mono); letter-spacing: .14em; text-transform: uppercase; margin-bottom: 8px; }
.story-close { font: italic 400 1.3rem/1.45 var(--serif); color: var(--fg); border-top: 1px solid var(--line); padding-top: 22px; }
/* Acceptance letters: framed like the original proof wall. */
.letter { margin: 0; background: var(--card); border: 1px solid var(--line); padding: 12px; transition: border-color .2s, transform .2s; }
.letter img { display: block; width: 100%; height: auto; }
.letter figcaption { margin-top: 12px; font: 500 11.5px/1.3 var(--mono); letter-spacing: .14em; text-transform: uppercase; color: var(--accent); text-align: center; }
a:hover > .letter { border-color: var(--line-strong); }

.quotes { columns: 1; column-gap: 20px; }
@media (min-width: 760px) { .quotes { columns: 2; } }
@media (min-width: 1100px) { .quotes { columns: 3; } }
.quote { break-inside: avoid; margin: 0 0 20px; background: var(--card); border: 1px solid var(--card-line); padding: 26px 26px 22px; }
.quote blockquote { margin: 0; color: var(--body); font-size: 1rem; line-height: 1.65; }
.quote blockquote p + p { margin-top: .8em; }
.quote figcaption { margin-top: 18px; padding-top: 14px; border-top: 1px solid var(--line); color: var(--fg); font-weight: 600; font-size: .95rem; }
.quote figcaption span { display: block; font-weight: 400; color: var(--muted); font-size: .88rem; margin-top: 2px; }
.quote.feature { border-color: rgba(200, 169, 107, .6); }

.pull { margin: 0; }
.pull blockquote { margin: 0; font: italic 400 clamp(1.2rem, 1.05rem + .5vw, 1.45rem)/1.45 var(--serif); color: var(--fg); }
.pull figcaption { margin-top: 14px; font-size: .92rem; color: var(--muted); }

/* Letters wall. */
.wall { columns: 1; column-gap: 18px; }
@media (min-width: 560px) { .wall { columns: 2; } }
@media (min-width: 1000px) { .wall { columns: 3; } }
@media (min-width: 1100px) { .wall-4 { columns: 4; } }
.wall .letter { break-inside: avoid; margin-bottom: 18px; display: block; }

/* People. */
.person { display: grid; gap: 28px; grid-template-columns: 1fr; align-items: start; }
@media (min-width: 900px) { .person { grid-template-columns: 340px minmax(0, 1fr); gap: 56px; } }
.person-photo { margin: 0; }
.person-photo img { display: block; width: 100%; height: auto; filter: grayscale(.25) contrast(1.05); }
.person-photo figcaption { margin-top: 12px; }
.person-photo figcaption b { display: block; font: 400 1.3rem/1.3 var(--serif); color: var(--fg); }
.person-photo figcaption span { font: 500 11.5px/1.4 var(--mono); letter-spacing: .12em; text-transform: uppercase; color: var(--accent); }
.tags { display: flex; flex-wrap: wrap; gap: 8px; list-style: none; margin: 22px 0 0; padding: 0; }
.tags li { padding: 7px 12px; border: 1px solid var(--line); font-size: .88rem; color: var(--fg); }

.timeline { list-style: none; margin: 0; padding: 0; border-left: 1px solid var(--line); }
.timeline > li { position: relative; padding: 0 0 36px 28px; }
.timeline > li::before { content: ''; position: absolute; left: -5px; top: 7px; width: 9px; height: 9px; border-radius: 50%; background: var(--bg); border: 1.5px solid var(--accent); }
.timeline > li:last-child { padding-bottom: 0; }
.timeline .when { font: 500 12px/1.3 var(--mono); letter-spacing: .14em; text-transform: uppercase; color: var(--accent); }
.timeline .h4 { margin: 6px 0 10px; font: 500 1.25rem/1.3 var(--serif); }
.timeline figure { margin: 14px 0; }
.timeline figure img { display: block; width: 100%; height: auto; border: 1px solid var(--card-line); }
.timeline figcaption { margin-top: 8px; font-size: .84rem; color: var(--muted); }
.tl-photos { display: grid; gap: 12px; grid-template-columns: 1fr; }
@media (min-width: 560px) { .tl-photos { grid-template-columns: 1fr 1fr; } .tl-photos img { aspect-ratio: 3 / 2; object-fit: cover; } }

/* Callout band: one closing step. */
.cta-band { text-align: center; }
.cta-band .h2 { max-width: 20ch; margin: 0 auto; }
.cta-band .lead { margin-left: auto; margin-right: auto; }
.cta-band .btn-row { justify-content: center; }

/* FAQ accordion. */
.faq { border-top: 1px solid var(--line); }
.faq details { border-bottom: 1px solid var(--line); }
.faq summary {
    list-style: none; cursor: pointer;
    display: flex; justify-content: space-between; align-items: flex-start; gap: 20px;
    padding: 20px 0; color: var(--fg); font: 600 1.05rem/1.45 var(--sans);
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: '+'; flex: none; font: 400 1.5rem/1 var(--sans); color: var(--accent); transition: transform .2s; margin-top: -1px; }
.faq details[open] summary::after { transform: rotate(45deg); }
.faq .faq-a { padding: 0 0 22px; max-width: var(--read); color: var(--body); }
.faq .faq-a a { color: var(--fg); text-decoration: underline; text-decoration-color: var(--accent); text-underline-offset: 3px; }
.faq-group + .faq-group { margin-top: 48px; }
.faq-group > .h3 { margin-bottom: 8px; }

/* Keyboard focus, everywhere. */
.site a:focus-visible, .site button:focus-visible, .site summary:focus-visible {
    outline: 2px solid var(--gold); outline-offset: 3px;
}

@media (prefers-reduced-motion: reduce) {
    .site *, .site *::before, .site *::after { transition: none !important; animation: none !important; }
}
.faq-q { font: inherit; color: inherit; margin: 0; }

/* Playfair's default figures are old-style, so "100" reads "1oo" and "0" reads
   "o". Lining figures everywhere; !important because every `font` shorthand
   above resets font-variant-numeric. */
.site, .site *, .site-header *, .site-footer * { font-variant-numeric: lining-nums !important; }

/* Small screens: the hours bar keeps only its middle caption; people cards
   get a smaller photo so the text column stays readable. */
@media (max-width: 599px) {
    .hours-total span:first-child, .hours-total span:last-child { display: none; }
    .hours-total { justify-content: center; }
}

/* pricing.html keeps its own phone CTA bar; lift the WhatsApp button above it. */
@media (max-width: 767px) { body:has(.mobile-sticky-cta.visible) .wa-fab { bottom: 92px; } }

/* Testimonial carousel (site-slider.js): a scroll-snap filmstrip. */
.slider-head { display: flex; flex-wrap: wrap; justify-content: space-between; align-items: flex-end; gap: 20px; margin-bottom: 36px; }
.slider-head .h2 { margin: 0; }
.slider-ctrl { display: flex; align-items: center; gap: 10px; }
.slider-count { font: 500 13px/1 var(--mono); letter-spacing: .1em; color: var(--muted); margin-right: 6px; }
.slider-btn {
    width: 48px; height: 48px; display: grid; place-items: center; cursor: pointer;
    background: transparent; border: 1px solid var(--line-strong); color: var(--fg); font: 400 18px/1 var(--sans);
    transition: border-color .18s, color .18s;
}
.slider-btn:hover { border-color: var(--accent); color: var(--accent); }
.slider {
    display: flex; gap: 20px; overflow-x: auto; scroll-snap-type: x mandatory; scroll-behavior: smooth;
    scrollbar-width: none; -ms-overflow-style: none; padding-bottom: 4px; outline-offset: 6px;
}
.slider::-webkit-scrollbar { display: none; }
.slide {
    flex: 0 0 88%; scroll-snap-align: start; margin: 0;
    display: flex; flex-direction: column;
    background: var(--card); border: 1px solid var(--card-line); padding: 30px 30px 26px;
}
@media (min-width: 760px) { .slide { flex-basis: calc((100% - 20px) / 2); } }
@media (min-width: 1100px) { .slide { flex-basis: calc((100% - 40px) / 3); } }
.slide.feature { border-color: rgba(200, 169, 107, .6); }
.slide-mark { display: block; height: 30px; font: 400 4.2rem/1 var(--serif); color: var(--accent); opacity: .55; }
.slide blockquote { margin: 10px 0 0; color: var(--body); font-size: 1.02rem; line-height: 1.7; }
.slide blockquote p + p { margin-top: .8em; }
.slide blockquote.clamped { max-height: 20.4em; overflow: hidden; -webkit-mask-image: linear-gradient(to bottom, #000 72%, transparent); mask-image: linear-gradient(to bottom, #000 72%, transparent); }
.slide-more {
    align-self: flex-start; margin-top: 12px; padding: 0 0 2px; cursor: pointer;
    background: none; border: 0; border-bottom: 1.5px solid var(--accent);
    color: var(--fg); font: 600 .9rem/1.4 var(--sans);
}
.slide figcaption { margin-top: auto; padding-top: 22px; }
.slide figcaption::before { content: ''; display: block; height: 1px; background: var(--line); margin-bottom: 16px; }
.slide figcaption b { display: block; color: var(--fg); font-weight: 600; }
.slide figcaption span { display: block; color: var(--muted); font-size: .9rem; margin-top: 2px; }
.slide-tag { display: inline-block; margin-top: 10px; font: 500 11.5px/1.3 var(--mono); letter-spacing: .12em; text-transform: uppercase; color: var(--accent); }
@media print { .slide blockquote.clamped { max-height: none; overflow: visible; -webkit-mask-image: none; mask-image: none; } }
/* The ACC letter is a tall phone screenshot: show its top, link to the whole. */
.wall .letter img { max-height: 460px; object-fit: cover; object-position: top; }

/* Letter gallery (home + results): a tidy grid, each letter on a white sheet.
   Wide letters fit whole; tall screenshots (.tall) show their top. Tap opens
   the full image. */
.letters { display: grid; gap: 18px; grid-template-columns: repeat(2, minmax(0, 1fr)); }
@media (min-width: 900px) { .letters { grid-template-columns: repeat(3, minmax(0, 1fr)); } }
.letters > a { display: block; text-decoration: none; }
.letters .letter { height: 100%; display: flex; flex-direction: column; }
.letters .sheet { display: block; aspect-ratio: 16 / 10; background: #fff; overflow: hidden; }
.letters .sheet img { width: 100%; height: 100%; object-fit: contain; }
.letters .tall .sheet img { object-fit: cover; object-position: top; }
.letters .letter figcaption { margin-top: auto; padding-top: 12px; }
@media (max-width: 520px) { .letters { gap: 12px; } .letters .letter { padding: 8px; } .letters .letter figcaption { font-size: 10px; letter-spacing: .08em; } }

/* Conference names, scrolling (home). Two identical sets slide one set-width
   and loop; hover pauses; reduced motion shows one static, wrapped row. */
.marquee { overflow: hidden; -webkit-mask-image: linear-gradient(90deg, transparent, #000 8%, #000 92%, transparent); mask-image: linear-gradient(90deg, transparent, #000 8%, #000 92%, transparent); }
.marquee-track { display: flex; width: max-content; animation: tsq-marquee 36s linear infinite; }
.marquee:hover .marquee-track { animation-play-state: paused; }
.marquee-set { display: flex; gap: 56px; padding: 0 56px 0 0; margin: 0; list-style: none; }
.marquee-set li { font: 600 clamp(1.2rem, 1rem + .7vw, 1.6rem)/1.3 var(--serif); color: var(--fg); opacity: .82; white-space: nowrap; cursor: help; }
@keyframes tsq-marquee { to { transform: translateX(-50%); } }
@media (prefers-reduced-motion: reduce) {
    .marquee { -webkit-mask-image: none; mask-image: none; }
    .marquee-track { width: auto; justify-content: center; }
    .marquee-set { flex-wrap: wrap; justify-content: center; gap: 10px 30px; padding: 0; }
    .marquee-set[aria-hidden] { display: none; }
}

/* Home hero: the original two-line composition, centred, with air.
   Each sentence on its own line; a soft gold light behind the headline. */
.hero-home { background: radial-gradient(ellipse 70% 55% at 50% 0%, rgba(200, 169, 107, .11), transparent 70%), var(--bg); }
.hero-title { font-size: clamp(2.5rem, 1.2rem + 4.3vw, 4.7rem); line-height: 1.14; letter-spacing: -.02em; margin: 6px auto 0; text-wrap: balance; }
.hero-home .lead { margin-top: 28px; max-width: 58ch; }
.hero-home .btn-row { margin-top: 36px; }
.hero-books { max-width: 920px; margin: clamp(48px, 7vw, 80px) auto 0; }
@supports ((-webkit-background-clip: text) or (background-clip: text)) {
    .shimmer {
        background: linear-gradient(100deg, #C8A96B 20%, #F1DFAE 42%, #D4AF37 55%, #C8A96B 80%);
        background-size: 220% 100%;
        -webkit-background-clip: text; background-clip: text; color: transparent;
        padding-right: .08em;
        animation: tsq-shimmer 6s ease-in-out infinite;
    }
}
@keyframes tsq-shimmer { 0%, 100% { background-position: 110% 0; } 50% { background-position: -10% 0; } }

/* No orphaned last words, on every page that loads this file (guides,
   legal and pricing included): headings balance their lines, and running
   text avoids ending on a lone word. Older browsers just wrap as before. */
h1, h2, h3, h4, .h1, .h2, .h3, .h4 { text-wrap: balance; }
p, li, blockquote, figcaption, dd, td { text-wrap: pretty; }
/* A heading's forced break before its last phrase starts a new block, so
   each sentence balances on its own (pricing's headings included). The .nb
   spans are site-nav.js keeping a last word pair together; never a phrase. */
:is(h1, h2, h3) > br:has(+ :is(span:not(.nb), em):last-child) { display: none; }
:is(h1, h2, h3) > br + :is(span:not(.nb), em):last-child { display: block; }
@media (max-width: 480px) { .book .h4 { font-size: .94rem; } }

/* ── Tau Square Studio ─────────────────────────────────────────────────────
   studio.html, and the Studio bands on the home page and What you get.
   Softer than the rest of the site on purpose: glass, light and round
   corners say "software"; the navy and gold say Tau Square. */
.nav-studio::after {
    content: ''; display: inline-block; width: 6px; height: 6px; margin-left: 7px; vertical-align: 2px;
    border-radius: 50%; background: var(--gold); box-shadow: 0 0 10px rgba(200, 169, 107, .9);
}
/* Seven menu items: a little tighter until there's room. */
@media (min-width: 1100px) and (max-width: 1259px) { .nav-links { gap: 19px; } .nav-actions { gap: 14px; } }

.glass {
    position: relative; border-radius: 18px; padding: clamp(22px, 3vw, 30px);
    background: linear-gradient(180deg, rgba(255, 255, 255, .055), rgba(255, 255, 255, .015));
    border: 1px solid rgba(255, 255, 255, .09);
}
.glass.gold { border-color: rgba(200, 169, 107, .5); box-shadow: 0 30px 90px -40px rgba(200, 169, 107, .35); }

/* The steps, joined by one gold line. */
.line-steps { list-style: none; margin: 0; padding: 0; position: relative; }
.line-steps::before { content: ''; position: absolute; left: 13px; top: 14px; bottom: 14px; width: 2px; background: linear-gradient(var(--gold), rgba(200, 169, 107, .15)); }
.line-steps li { position: relative; padding: 9px 0 9px 42px; color: var(--fg); font-weight: 500; line-height: 1.4; }
.line-steps li::before {
    content: '✓'; position: absolute; left: 0; top: 50%; transform: translateY(-50%); display: grid; place-items: center; width: 28px; height: 28px;
    border-radius: 50%; background: var(--ink-950); border: 1.5px solid var(--gold); color: var(--gold); font: 700 12px/1 var(--sans);
}
.line-steps .sub { color: var(--muted); font-weight: 400; font-size: .92rem; }

/* τ² in a slowly turning ring of light. */
.tau-orb { position: relative; display: inline-grid; place-items: center; width: 96px; height: 96px; }
.tau-orb::before {
    content: ''; position: absolute; inset: 0; border-radius: 50%;
    background: conic-gradient(from 0deg, transparent, rgba(200, 169, 107, .85), transparent 40%, rgba(15, 106, 120, .8), transparent 75%);
    -webkit-mask: radial-gradient(farthest-side, transparent calc(100% - 2px), #000 calc(100% - 1px));
    mask: radial-gradient(farthest-side, transparent calc(100% - 2px), #000 calc(100% - 1px));
    animation: tsq-spin 9s linear infinite;
}
.tau-orb::after { content: ''; position: absolute; inset: 14px; border-radius: 50%; background: radial-gradient(circle, rgba(200, 169, 107, .28), transparent 70%); filter: blur(6px); }
.tau-orb span {
    position: relative; z-index: 1; font: italic 500 2.6rem/1 var(--serif);
    background: linear-gradient(120deg, #F1DFAE, #C8A96B 60%, #D4AF37); -webkit-background-clip: text; background-clip: text; color: transparent;
}
.tau-orb.lg { width: 140px; height: 140px; }
.tau-orb.lg span { font-size: 3.8rem; }
@keyframes tsq-spin { to { transform: rotate(360deg); } }

/* A Studio band elsewhere on the site: the words, then the steps. */
.studio-band { overflow: hidden; isolation: isolate; }
.studio-band::before {
    content: ''; position: absolute; inset: 0; z-index: -1;
    background: radial-gradient(ellipse 50% 60% at 85% 50%, rgba(15, 106, 120, .2), transparent 70%), radial-gradient(ellipse 45% 55% at 10% 20%, rgba(200, 169, 107, .1), transparent 70%);
}
.studio-band .tau-orb { margin-bottom: 18px; }
/* Tau, the face of τ² AI (tau-bot.svg): hovers gently beside its section. */
.tau-bot { display: block; width: 150px; height: auto; margin: -18px 0 4px -14px; filter: drop-shadow(0 18px 30px rgba(200, 169, 107, .25)); animation: tsq-hover 5.5s ease-in-out infinite; }
.tau-bot-lg { width: 230px; margin: -30px 0 0 -26px; }
.tau-hello { margin: 0 0 18px; font: italic 400 1.15rem/1.4 var(--serif); color: var(--gold); }
@keyframes tsq-hover { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-8px); } }
@media (prefers-reduced-motion: reduce) { .tau-bot { animation: none; } }
@media (prefers-reduced-motion: reduce) { .tau-orb::before { animation: none; } }