/* =============================================================================
   Location: /public/assets/landing.css
   Function: Home page – "blackboard grid" look from the approved design:
             navy hero with floating formulas and a self-drawing graph, report mock-up
             with a red-pen correction, stage cards with drawn illustrations,
             class grid with statuses, number-line steps. No framework, CSS only.
   Version:  1.2.0 · Build 2026.10.27.0100
   1.2.0 status „Dostępna” (pill--live); 1.1.0 JSXGraph demonstrations, team cards from tutor profiles
   ============================================================================= */

:root {
  --navy: #0F1B4D; --yellow: #FFD84D; --blue: #2346D8; --ink: #11141A; --text: #3A4150;
  --muted: #5B6170; --line: #DADFE8; --paper: #FBFCFE;
  --ok-fg: #146C33; --ok-bg: #E3F4E8; --gap-fg: #8A3A0B; --gap-bg: #FCE9DD;
  --test-fg: #1D3FB8; --test-bg: #E6ECFF; --prep-fg: #8A4A06; --prep-bg: #FDF0DC; --plan-fg: #4A505C; --plan-bg: #EEF0F3;
  --display: 'Bricolage Grotesque', system-ui, sans-serif;
  --body: 'IBM Plex Sans', system-ui, sans-serif;
  --math: 'STIX Two Text', 'Times New Roman', serif;
  --mono: 'IBM Plex Mono', ui-monospace, monospace;
}
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--paper); color: #171A21; font-family: var(--body); -webkit-font-smoothing: antialiased; line-height: 1.5; }
h1, h2, h3, p { margin: 0; }
a { color: #1D3FB8; } a:hover { color: #142C85; }
:focus-visible { outline: 3px solid var(--yellow); outline-offset: 3px; border-radius: 6px; }
.skip { position: absolute; left: -9999px; } .skip:focus { left: 1rem; top: .5rem; z-index: 50; background: #fff; padding: .5rem 1rem; }
.wrap { max-width: 1200px; margin: 0 auto; padding-inline: 24px; }
.visually-hidden { position: absolute !important; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

/* ---------- animations ---------- */
@keyframes float { 0%, 100% { transform: translateY(0) rotate(0); } 50% { transform: translateY(-16px) rotate(6deg); } }
@keyframes rise { from { opacity: 0; transform: translateY(22px); } to { opacity: 1; transform: none; } }
@keyframes draw { from { stroke-dashoffset: 600; } to { stroke-dashoffset: 0; } }
@keyframes drawlg { from { stroke-dashoffset: 1600; } to { stroke-dashoffset: 0; } }
@keyframes grow { from { transform: scaleX(0); } to { transform: scaleX(1); } }
@keyframes mark { from { background-size: 0% 100%; } to { background-size: 100% 100%; } }
@keyframes strike { from { transform: rotate(-14deg) scaleX(0); } to { transform: rotate(-14deg) scaleX(1); } }
@keyframes pop { from { opacity: 0; transform: scale(.5) rotate(-14deg); } to { opacity: 1; transform: rotate(-6deg); } }
@keyframes blink { 0%, 100% { opacity: 1; } 50% { opacity: .25; } }
.float { position: absolute; font-family: var(--math); font-style: italic; color: rgba(255,255,255,.16); white-space: nowrap; animation: float 9s ease-in-out infinite; pointer-events: none; }
.rise { animation: rise .8s cubic-bezier(.2,.7,.2,1) both; }
.draw-lg { stroke-dasharray: 1600; animation: drawlg 2.6s ease-out .3s both; }
@supports (animation-timeline: view()) {
  .reveal { animation: rise linear both; animation-timeline: view(); animation-range: entry 0% entry 70%; }
  .draw { stroke-dasharray: 600; animation: draw linear both; animation-timeline: view(); animation-range: entry 10% cover 45%; }
  .grow { transform-box: fill-box; transform-origin: left center; animation: grow linear both; animation-timeline: view(); animation-range: entry 25% cover 45%; }
}
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { animation: none !important; transition: none !important; } html { scroll-behavior: auto; } }

/* ---------- buttons ---------- */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: .5rem; min-height: 52px; padding: 14px 24px; border-radius: 12px; font-weight: 600; font-size: 17px; text-decoration: none; transition: transform .15s ease, box-shadow .15s ease; }
.btn:hover { transform: translateY(-2px); box-shadow: 0 10px 22px rgba(10,16,48,.22); }
.btn--yellow { background: var(--yellow); color: var(--navy); } .btn--yellow:hover { color: var(--navy); }
.btn--ghost { color: #fff; border: 1.5px solid rgba(255,255,255,.45); } .btn--ghost:hover { color: #fff; }
.btn--sm { min-height: 44px; padding: 10px 18px; font-size: 15px; border-radius: 10px; }

/* ---------- hero (blackboard) ---------- */
.board { position: relative; overflow: hidden; background-color: var(--navy);
  background-image: linear-gradient(rgba(255,255,255,.045) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,.045) 1px, transparent 1px),
    linear-gradient(rgba(255,255,255,.09) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,.09) 1px, transparent 1px);
  background-size: 24px 24px, 24px 24px, 120px 120px, 120px 120px; }
.board--plain { background-size: 24px 24px, 24px 24px, 0 0, 0 0; }
.decor { position: absolute; inset: 0; pointer-events: none; }
.decor svg { position: absolute; right: -40px; top: 60px; width: 640px; max-width: 70%; height: auto; opacity: .55; }

.topbar { position: relative; display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 16px; padding-block: 18px; }
.brand { display: flex; align-items: center; gap: 12px; color: #fff; text-decoration: none; font-family: var(--display); font-weight: 700; font-size: 20px; letter-spacing: -.01em; }
.brand:hover { color: #fff; }
.mainnav { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 26px; font-size: 15px; font-weight: 500; }
.mainnav a:not(.btn) { color: #DCE3FA; text-decoration: none; }
.mainnav a:not(.btn):hover { color: #fff; }

.hero { position: relative; display: flex; flex-wrap: wrap; align-items: center; gap: 56px; padding-block: 56px 96px; }
.hero-text { flex: 1 1 460px; min-width: 0; display: flex; flex-direction: column; gap: 24px; }
.formula-line { font-family: var(--mono); font-size: 14px; color: var(--yellow); letter-spacing: .02em; }
.cursor { display: inline-block; width: 2px; height: 1em; background: var(--yellow); vertical-align: -2px; margin-left: 4px; animation: blink 1.1s steps(1) infinite; }
.hero h1 { font-family: var(--display); font-weight: 800; font-size: clamp(2.5rem, 5vw, 4.3rem); line-height: 1.02; letter-spacing: -.028em; color: #fff; }
.mark { color: var(--yellow); background-image: linear-gradient(transparent 84%, rgba(255,216,77,.45) 84%); background-repeat: no-repeat; background-size: 100% 100%; -webkit-box-decoration-break: clone; box-decoration-break: clone; animation: mark 1.1s ease-out .9s both; }
.hero-lead { font-size: 19px; color: #C9D3F5; max-width: 560px; }
.cta-row { display: flex; flex-wrap: wrap; gap: 12px; }
.checks { list-style: none; margin: 0; padding: 0; display: flex; flex-wrap: wrap; gap: 8px 24px; font-size: 15px; color: #DCE3FA; }
.checks li { display: flex; align-items: center; gap: 8px; }
.test-note { font-size: 14px; color: #C9D3F5; border-left: 3px solid var(--yellow); padding-left: 12px; }

/* report mock-up */
.report { flex: 1 1 420px; min-width: 0; margin: 0; background: #fff; border-radius: 20px; box-shadow: 0 24px 60px rgba(4,8,30,.45); padding: 28px; display: flex; flex-direction: column; gap: 18px; animation-delay: .25s; }
.report-head { display: flex; justify-content: space-between; align-items: flex-start; gap: 12px; flex-wrap: wrap; }
.eyebrow-mono { font-family: var(--mono); font-size: 12px; color: var(--muted); text-transform: uppercase; letter-spacing: .06em; display: block; }
.report-title { font-family: var(--display); font-weight: 700; font-size: 24px; color: var(--ink); }
.chip { font-size: 13px; color: #4A505C; background: #F2F4F8; border-radius: 999px; padding: 6px 12px; }
.report-rows { list-style: none; margin: 0; padding: 0; }
.report-rows li { display: flex; justify-content: space-between; align-items: center; gap: 12px; padding: 11px 0; border-top: 1px solid #EEF0F4; font-size: 15px; }
.report-rows li:last-child { border-bottom: 1px solid #EEF0F4; }
.pill { font-size: 13px; font-weight: 600; border-radius: 999px; padding: 5px 12px; white-space: nowrap; }
.pill--ok { color: var(--ok-fg); background: var(--ok-bg); } .pill--gap { color: var(--gap-fg); background: var(--gap-bg); } .pill--none { color: var(--plan-fg); background: var(--plan-bg); }
.pill--live { color: var(--ok-fg); background: var(--ok-bg); } .pill--test { color: var(--test-fg); background: var(--test-bg); } .pill--prep { color: var(--prep-fg); background: var(--prep-bg); } .pill--plan { color: var(--plan-fg); background: var(--plan-bg); }
.errbox { background-color: #F7F9FD; background-image: linear-gradient(#E9EEF7 1px, transparent 1px), linear-gradient(90deg, #E9EEF7 1px, transparent 1px); background-size: 16px 16px; border: 1px solid #E3E7EF; border-radius: 14px; padding: 16px 18px; display: flex; flex-direction: column; gap: 10px; font-size: 14px; color: #2E3440; }
.eq { display: flex; align-items: center; gap: 10px; font-size: 22px; color: var(--ink); flex-wrap: wrap; font-family: var(--math); }
.frac { display: inline-flex; flex-direction: column; align-items: center; vertical-align: middle; line-height: 1.05; font-family: var(--math); padding: 0 2px; }
.frac > span:last-child { border-top: 1.6px solid currentColor; padding-top: 2px; min-width: 100%; text-align: center; }
.strike { position: relative; display: inline-flex; color: var(--gap-fg); }
.strike::after { content: ''; position: absolute; left: -6px; right: -6px; top: 48%; height: 2.5px; border-radius: 2px; background: #D93A2B; transform: rotate(-14deg) scaleX(1); transform-origin: left center; animation: strike .45s ease-out 1.9s both; }
.fix { display: inline-block; font-family: 'Caveat', cursive; font-weight: 700; font-size: 30px; color: #D93A2B; transform: rotate(-6deg); animation: pop .5s cubic-bezier(.3,1.6,.5,1) 2.4s both; }
.report-foot { display: flex; flex-wrap: wrap; justify-content: space-between; align-items: center; gap: 12px; font-size: 13px; color: var(--muted); }

/* ---------- sections ---------- */
.section { padding-block: 96px; }
.section--tight-bottom { padding-bottom: 40px; }
.section--tight-top { padding-top: 40px; }
.section-head { display: flex; flex-direction: column; gap: 14px; max-width: 760px; margin-bottom: 40px; }
.kicker { font-family: var(--mono); font-size: 14px; color: var(--blue); }
.section h2 { font-family: var(--display); font-weight: 800; font-size: clamp(2rem, 3.6vw, 3rem); line-height: 1.08; letter-spacing: -.022em; color: var(--ink); }
.section-lead { font-size: 18px; color: var(--text); }
.grid { display: grid; gap: 22px; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }

.card { background: #fff; border: 1.5px solid var(--line); border-radius: 20px; overflow: hidden; display: flex; flex-direction: column; transition: transform .25s ease, box-shadow .25s ease; }
.card:hover { transform: translateY(-5px); box-shadow: 0 18px 40px rgba(15,27,77,.12); }
.card--accent { border: 2px solid var(--blue); }
.card-illo { background-color: #F7F9FD; background-image: linear-gradient(#E6EBF5 1px, transparent 1px), linear-gradient(90deg, #E6EBF5 1px, transparent 1px); background-size: 20px 20px; border-bottom: 1px solid #E3E7EF; padding: 16px; }
.card-illo svg { width: 100%; height: 140px; display: block; }
.card-body { padding: 24px 28px 28px; display: flex; flex-direction: column; gap: 14px; flex: 1; }
.card-meta { display: flex; justify-content: space-between; align-items: center; gap: 12px; flex-wrap: wrap; font-family: var(--mono); font-size: 13px; color: var(--muted); }
.card-meta .pill { font-family: var(--body); }
.card h3 { font-family: var(--display); font-weight: 700; font-size: 28px; line-height: 1.15; color: var(--ink); }
.card p { font-size: 16px; color: var(--text); }
.card-link { margin-top: auto; font-weight: 600; text-decoration: none; color: var(--blue); min-height: 44px; display: inline-flex; align-items: center; }
.card-soon { margin-top: auto; font-size: 14px; color: var(--muted); min-height: 44px; display: inline-flex; align-items: center; }

.classes-head { display: flex; flex-wrap: wrap; justify-content: space-between; align-items: flex-end; gap: 16px; margin-bottom: 28px; }
.classes-head h2 { font-size: 30px; font-weight: 700; }
.legend { list-style: none; margin: 0; padding: 0; display: flex; flex-wrap: wrap; gap: 8px; }
.school { background-color: #fff; background-image: linear-gradient(#EEF1F7 1px, transparent 1px), linear-gradient(90deg, #EEF1F7 1px, transparent 1px); background-size: 24px 24px; border: 1px solid var(--line); border-radius: 20px; padding: 24px; display: flex; flex-direction: column; gap: 16px; margin-bottom: 28px; }
.school-head { display: flex; flex-wrap: wrap; justify-content: space-between; align-items: baseline; gap: 8px; }
.school-head h3 { font-size: 18px; font-weight: 600; color: var(--ink); }
.set { font-family: var(--math); font-style: italic; font-size: 17px; color: var(--muted); }
.tiles { display: grid; grid-template-columns: repeat(auto-fill, minmax(124px, 1fr)); gap: 12px; }
.tile { display: flex; flex-direction: column; gap: 8px; padding: 16px; border-radius: 16px; min-height: 160px; background: #fff; border: 1px solid var(--line); color: inherit; text-decoration: none; transition: transform .2s ease, box-shadow .2s ease; }
a.tile:hover { transform: translateY(-4px); box-shadow: 0 12px 26px rgba(15,27,77,.12); color: inherit; }
.tile--key { background: #FAFBFF; border: 2px solid var(--blue); }
.tile-top { display: flex; justify-content: space-between; align-items: flex-start; gap: 8px; font-size: 13px; color: var(--muted); }
.tile-sym { font-family: var(--math); font-style: italic; font-size: 20px; line-height: 1; color: #7C88A8; }
.tile-num { font-family: var(--display); font-weight: 800; font-size: 44px; line-height: 1; color: var(--ink); }
.tile .pill { align-self: flex-start; font-size: 12px; padding: 4px 10px; }
.tile-tag { font-size: 12px; font-weight: 600; color: var(--blue); }

.white { background: #fff; border-block: 1px solid #E3E7EF; }
.steps { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); row-gap: 48px; }
.steps li { position: relative; border-top: 2px solid var(--ink); padding: 0 32px 0 0; display: flex; flex-direction: column; gap: 12px; }
.steps li:last-child::after { content: ''; position: absolute; right: 0; top: -8px; border-left: 12px solid var(--ink); border-top: 7px solid transparent; border-bottom: 7px solid transparent; }
.step-num { font-family: var(--mono); font-size: 16px; color: #fff; background: var(--blue); border-radius: 999px; width: 40px; height: 40px; margin-top: -21px; display: inline-flex; align-items: center; justify-content: center; box-shadow: 0 0 0 6px #fff; }
.steps h3 { font-size: 19px; font-weight: 600; color: var(--ink); }
.steps p { font-size: 16px; color: var(--text); }

.trust .section h2, .trust h2 { color: #fff; }
.trust-kicker { font-family: var(--math); font-style: italic; font-size: 20px; color: var(--yellow); }
.trust-card { border: 1px solid rgba(255,255,255,.16); background: rgba(255,255,255,.04); border-radius: 18px; padding: 24px; display: flex; flex-direction: column; gap: 12px; transition: transform .25s ease; }
.trust-card:hover { transform: translateY(-4px); }
.trust-card h3 { font-size: 19px; font-weight: 600; color: #fff; }
.trust-card p { font-size: 16px; color: #C9D3F5; }
.grid--4 { grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 20px; }

.soft { background: #F3F5FA; border-bottom: 1px solid #E3E7EF; }
.person { background: #fff; border: 1px solid var(--line); border-radius: 20px; padding: 28px; display: flex; flex-wrap: wrap; gap: 24px; align-items: flex-start; }
.photo { width: 116px; height: 116px; border-radius: 18px; background-color: #E6EAF2; background-image: linear-gradient(#D7DDEA 1px, transparent 1px), linear-gradient(90deg, #D7DDEA 1px, transparent 1px); background-size: 14px 14px; display: flex; align-items: center; justify-content: center; font-size: 13px; color: #4A505C; flex: none; }
.person-body { flex: 1 1 200px; min-width: 0; display: flex; flex-direction: column; gap: 8px; }
.person h3 { font-family: var(--display); font-weight: 700; font-size: 24px; color: var(--ink); }
.person-role { font-size: 15px; font-weight: 500; color: var(--blue); }
.person p { font-size: 16px; color: var(--text); }
.tags { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 4px; }
.tag { font-size: 13px; color: #2E3440; background: #F2F4F8; border-radius: 999px; padding: 6px 12px; }

.offer { background: #fff; border: 1px solid var(--line); border-radius: 20px; padding: 28px; display: flex; flex-direction: column; gap: 12px; transition: transform .25s ease, box-shadow .25s ease; }
.offer:hover { transform: translateY(-5px); box-shadow: 0 18px 40px rgba(15,27,77,.12); }
.offer-sym { font-family: var(--math); font-style: italic; font-size: 30px; color: var(--blue); }
.offer h3 { font-size: 20px; font-weight: 600; color: var(--ink); }
.offer p { font-size: 16px; color: var(--text); }
.price { margin-top: auto; font-family: var(--display); font-weight: 700; font-size: 22px; color: var(--ink); }
.price small { font-family: var(--body); font-weight: 400; font-size: 15px; color: var(--muted); }
.where { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 24px; }
.where-item { display: flex; align-items: center; gap: 10px; background: #fff; border: 1px solid var(--line); border-radius: 14px; padding: 12px 16px; font-size: 15px; }
.where-item strong { color: var(--ink); }

.cta { position: relative; overflow: hidden; background-color: var(--blue); background-image: linear-gradient(rgba(255,255,255,.08) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,.08) 1px, transparent 1px); background-size: 24px 24px; border-radius: 26px; padding: 60px 44px; display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 28px; }
.cta-text { position: relative; flex: 1 1 420px; min-width: 0; display: flex; flex-direction: column; gap: 12px; }
.cta h2 { font-family: var(--display); font-weight: 800; font-size: clamp(1.9rem, 3.4vw, 2.8rem); line-height: 1.08; letter-spacing: -.02em; color: #fff; }
.cta p { font-size: 18px; color: #fff; }
.cta .btn { position: relative; }

.footer { border-top: 1px solid #E3E7EF; background: #fff; }
.footer-in { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 24px; padding-block: 40px; font-size: 14px; color: #4A505C; }
.footer-brand { font-family: var(--display); font-weight: 700; font-size: 18px; color: var(--ink); }
.footer nav { display: flex; flex-wrap: wrap; gap: 8px 24px; align-items: flex-start; }
.footer nav a { color: #2E3440; }

@media (max-width: 640px) {
  .section { padding-block: 64px; }
  .hero { padding-block: 32px 64px; gap: 36px; }
  .report { padding: 20px; }
  .cta { padding: 40px 24px; }
  .steps li { padding-right: 0; }
}

/* ---------- 1.1.0: interactive demonstrations (JSXGraph) ---------- */
.demo-grid { display: grid; gap: 22px; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }
.demo { background: #fff; border: 1px solid var(--line); border-radius: 20px; padding: 22px; display: flex; flex-direction: column; gap: 10px; min-width: 0; }
.demo-tag { font-family: var(--mono); font-size: 12px; letter-spacing: .04em; color: var(--blue); text-transform: uppercase; }
.demo h3 { font-family: var(--display); font-weight: 700; font-size: 22px; color: var(--ink); }
.demo-board { width: 100%; aspect-ratio: 1 / 1; border-radius: 14px; background: #F7F9FD; border: 1px solid #E3E7EF; overflow: hidden; position: relative; touch-action: pan-y; }
.demo-board--short { aspect-ratio: 2 / 1; }
.demo-board .JXGtext { font-family: var(--body); color: var(--ink); }
.demo-fallback { position: absolute; inset: 0; display: grid; place-items: center; font-family: var(--math); font-size: 28px; color: #8A93A6; }
.demo-controls { display: grid; gap: 8px; }
.demo-controls label { display: grid; grid-template-columns: 5.5rem 1fr 3rem; align-items: center; gap: 10px; font-size: 15px; color: var(--text); }
.demo-controls label span { font-family: var(--math); font-style: italic; font-size: 17px; }
.demo-controls output { font-family: var(--mono); font-size: 15px; text-align: right; color: var(--ink); }
.demo-controls input[type=range] { width: 100%; accent-color: var(--blue); height: 32px; }
.demo-readout { font-family: var(--math); font-size: 17px; color: var(--ink); background: #FFF8D6; border-radius: 10px; padding: 10px 12px; min-height: 3.2em; }
.demo-note { margin-top: 16px; color: var(--muted); }

/* ---------- 1.1.0: team from tutor profiles ---------- */
.grid--team { grid-template-columns: repeat(auto-fill, minmax(min(100%, 420px), 1fr)); }
.person { flex-direction: column; gap: 18px; }
.person-head { display: flex; align-items: center; gap: 16px; }
.person-avatar { width: 72px; height: 72px; border-radius: 18px; flex: none; display: grid; place-items: center; background: var(--navy); color: var(--yellow); font-family: var(--display); font-weight: 800; font-size: 26px; letter-spacing: .02em; }
.person-body { gap: 12px; flex: 1 1 auto; width: 100%; }
.person-facts { margin: 4px 0 0; display: grid; gap: 8px; }
.person-facts div { display: grid; grid-template-columns: 8.5rem 1fr; gap: 8px; font-size: 15px; }
.person-facts dt { color: var(--muted); }
.person-facts dd { margin: 0; color: var(--ink); }
ul.tags { list-style: none; padding: 0; margin: 4px 0 0; }
.tag--mode { background: var(--ok-bg); color: var(--ok-fg); }
@media (max-width: 480px) {
  .grid--team, .demo-grid { grid-template-columns: 1fr; }
  .person-facts div { grid-template-columns: 1fr; gap: 0; }
  .demo-controls label { grid-template-columns: 4.8rem 1fr 2.6rem; }
}