/* Bead Brain — loose-leaf paper + colored pencil look */
@import url('https://fonts.googleapis.com/css2?family=Patrick+Hand&family=Nunito:wght@400;600;700;800&display=swap');

:root {
  --paper: #fffdf7;
  --line: rgba(120, 160, 210, 0.28);
  --margin: rgba(230, 110, 110, 0.35);
  --ink: #2f3440;
  --ink-soft: #5b6270;
  --graphite: #3b3f4a;
  --red: #e4572e;
  --orange: #f3a712;
  --yellow: #f7d154;
  --green: #6fb351;
  --teal: #29a19c;
  --blue: #4f86c6;
  --purple: #8e5ea2;
  --pink: #e86f9e;
  --brown: #8b5e34;
  --card: rgba(255, 255, 255, 0.72);
  --shadow: 0 2px 0 rgba(60, 50, 30, 0.08), 0 10px 24px -14px rgba(60, 50, 30, 0.25);
  --font-hand: 'Patrick Hand', 'Comic Sans MS', cursive;
  --font-body: 'Nunito', system-ui, -apple-system, sans-serif;
  --wobble: 255px 15px 225px 15px / 15px 225px 15px 255px;
  --wobble2: 15px 255px 15px 225px / 225px 15px 255px 15px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--ink);
  background-color: var(--paper);
  background-image:
    linear-gradient(to right, transparent 0, transparent 68px, var(--margin) 68px, var(--margin) 70px, transparent 70px),
    repeating-linear-gradient(to bottom, transparent 0, transparent 31px, var(--line) 31px, var(--line) 32px);
  background-attachment: fixed;
  line-height: 1.55;
  font-size: 17px;
}
@media (max-width: 720px) {
  body { background-image: repeating-linear-gradient(to bottom, transparent 0, transparent 31px, var(--line) 31px, var(--line) 32px); }
}

/* hole punches */
.holes { position: fixed; left: 18px; top: 0; bottom: 0; width: 26px; pointer-events: none; z-index: 0; }
.holes span { position: absolute; left: 0; width: 22px; height: 22px; border-radius: 50%; background: #efe9dc; box-shadow: inset 0 1px 3px rgba(0,0,0,0.25); }
.holes span:nth-child(1) { top: 12%; } .holes span:nth-child(2) { top: 50%; } .holes span:nth-child(3) { top: 88%; }
@media (max-width: 720px) { .holes { display: none; } }

a { color: var(--blue); }
h1, h2, h3, h4 { font-family: var(--font-hand); font-weight: 400; line-height: 1.15; color: var(--graphite); margin: 0.2em 0 0.4em; letter-spacing: 0.01em; }
h1 { font-size: 2.6rem; } h2 { font-size: 2rem; } h3 { font-size: 1.5rem; } h4 { font-size: 1.2rem; }
p { margin: 0.5em 0 0.9em; }
.hand { font-family: var(--font-hand); }
.muted { color: var(--ink-soft); }
.small { font-size: 0.9rem; }
.center { text-align: center; }
.c-red { color: var(--red); } .c-orange { color: var(--orange); } .c-green { color: var(--green); } .c-teal { color: var(--teal); } .c-blue { color: var(--blue); } .c-purple { color: var(--purple); } .c-pink { color: var(--pink); }

.wrap { max-width: 1020px; margin: 0 auto; padding: 18px 20px 80px 96px; position: relative; z-index: 1; }
@media (max-width: 720px) { .wrap { padding: 14px 16px 70px 16px; } }

/* top bar */
.topbar { display: flex; align-items: center; justify-content: space-between; gap: 14px; flex-wrap: wrap; margin-bottom: 14px; }
.topbar .logo { display: flex; align-items: center; gap: 10px; text-decoration: none; color: inherit; }
.topbar .logo svg { height: 54px; width: auto; }
.nav { display: flex; gap: 6px; flex-wrap: wrap; }
.nav a { font-family: var(--font-hand); font-size: 1.15rem; text-decoration: none; color: var(--graphite); padding: 6px 12px; border-radius: var(--wobble); border: 2px solid transparent; }
.nav a:hover, .nav a.active { border-color: var(--graphite); background: rgba(255,255,255,0.6); }

/* hand-drawn cards & buttons */
.card {
  background: var(--card);
  border: 2.5px solid var(--graphite);
  border-radius: var(--wobble);
  padding: 18px 22px;
  box-shadow: var(--shadow);
  margin: 14px 0;
  position: relative;
}
.card.alt { border-radius: var(--wobble2); }
.card.tint-teal { border-color: var(--teal); } .card.tint-orange { border-color: var(--orange); } .card.tint-blue { border-color: var(--blue); } .card.tint-purple { border-color: var(--purple); } .card.tint-green { border-color: var(--green); } .card.tint-red { border-color: var(--red); }
.card h2:first-child, .card h3:first-child { margin-top: 0; }

.btn {
  display: inline-flex; align-items: center; gap: 8px;
  font-family: var(--font-hand); font-size: 1.25rem; line-height: 1;
  padding: 11px 20px; border-radius: var(--wobble);
  border: 2.5px solid var(--graphite); background: #fff; color: var(--graphite);
  cursor: pointer; text-decoration: none; user-select: none;
  box-shadow: 2px 3px 0 rgba(47,52,64,0.9);
  transition: transform 80ms, box-shadow 80ms;
  position: relative; overflow: hidden;
}
.btn::after { content: ''; position: absolute; inset: 0; background: repeating-linear-gradient(35deg, rgba(255,255,255,0.35) 0 2px, transparent 2px 6px); pointer-events: none; }
.btn:hover { transform: translate(-1px, -1px); box-shadow: 3px 4px 0 rgba(47,52,64,0.9); }
.btn:active { transform: translate(2px, 3px); box-shadow: 0 0 0 rgba(0,0,0,0); }
.btn.primary { background: var(--teal); color: #fff; }
.btn.orange { background: var(--orange); color: #fff; }
.btn.red { background: var(--red); color: #fff; }
.btn.blue { background: var(--blue); color: #fff; }
.btn.purple { background: var(--purple); color: #fff; }
.btn.green { background: var(--green); color: #fff; }
.btn.ghost { background: transparent; box-shadow: none; }
.btn.sm { font-size: 1.05rem; padding: 7px 14px; }
.btn.big { font-size: 1.5rem; padding: 14px 28px; }
.btn[disabled] { opacity: 0.45; cursor: not-allowed; }
.btn-row { display: flex; gap: 10px; flex-wrap: wrap; align-items: center; margin: 12px 0; }

/* pencil underline highlight */
.hi { background: linear-gradient(transparent 55%, rgba(247, 209, 84, 0.65) 55%, rgba(247, 209, 84, 0.65) 92%, transparent 92%); padding: 0 3px; }
.hi-teal { background: linear-gradient(transparent 55%, rgba(41,161,156,0.3) 55%, rgba(41,161,156,0.3) 92%, transparent 92%); padding: 0 3px; }
.hi-pink { background: linear-gradient(transparent 55%, rgba(232,111,158,0.3) 55%, rgba(232,111,158,0.3) 92%, transparent 92%); padding: 0 3px; }

/* abacus */
.abacus-wrap { display: flex; flex-direction: column; align-items: center; gap: 8px; margin: 10px 0; }
.abacus { width: 100%; max-width: 560px; height: auto; display: block; touch-action: manipulation; }
.abacus .bead path:first-child { transition: filter 150ms; }
.abacus .bead:hover path:first-child { filter: brightness(1.12); }
.abacus-value { font-family: var(--font-hand); font-size: 2.2rem; color: var(--graphite); min-height: 1.2em; }
.abacus-caption { font-family: var(--font-body); font-size: 1.05rem; min-height: 1.6em; text-align: center; color: var(--ink); padding: 4px 12px; border-radius: 10px; }
.abacus-caption.big { font-family: var(--font-hand); font-size: 2rem; }
.abacus-caption.direct { background: rgba(111,179,81,0.18); }
.abacus-caption.small { background: rgba(243,167,18,0.2); }
.abacus-caption.big { background: rgba(79,134,198,0.18); }
.abacus-caption.combo { background: rgba(142,94,162,0.2); }
.col-hl { fill: rgba(247,209,84,0.35); stroke: var(--orange); stroke-width: 2; stroke-dasharray: 6 4; }
.col-hl.direct { fill: rgba(111,179,81,0.2); stroke: var(--green); }
.col-hl.small { fill: rgba(243,167,18,0.22); stroke: var(--orange); }
.col-hl.big { fill: rgba(79,134,198,0.2); stroke: var(--blue); }
.col-hl.combo { fill: rgba(142,94,162,0.22); stroke: var(--purple); }
.place-label { font-family: var(--font-hand); font-size: 12px; fill: var(--ink-soft); }
.abacus-sm .abacus { max-width: 360px; }

/* trail map */
.trail { display: grid; grid-template-columns: repeat(auto-fill, minmax(170px, 1fr)); gap: 14px; margin: 18px 0; }
.stage-node { text-decoration: none; color: inherit; display: flex; flex-direction: column; align-items: center; text-align: center; padding: 14px 10px 12px; border: 2.5px solid var(--graphite); border-radius: var(--wobble); background: rgba(255,255,255,0.7); box-shadow: var(--shadow); transition: transform 120ms; position: relative; }
.stage-node:nth-child(even) { border-radius: var(--wobble2); }
.stage-node:hover { transform: translateY(-3px) rotate(-0.5deg); }
.stage-node svg { width: 74px; height: 74px; }
.stage-node .name { font-family: var(--font-hand); font-size: 1.45rem; margin-top: 6px; }
.stage-node .sub { font-size: 0.85rem; color: var(--ink-soft); line-height: 1.3; }
.stage-node.locked { opacity: 0.55; filter: grayscale(0.6); }
.stage-node.done { border-color: var(--green); }
.stage-node .num { position: absolute; top: -12px; left: -8px; background: var(--yellow); border: 2px solid var(--graphite); border-radius: 50%; width: 30px; height: 30px; display: grid; place-items: center; font-family: var(--font-hand); font-size: 1.1rem; }
.stage-node .check { position: absolute; top: -10px; right: -8px; font-size: 1.4rem; }

/* progress bars, chips */
.bar { height: 14px; background: rgba(0,0,0,0.07); border: 2px solid var(--graphite); border-radius: 10px; overflow: hidden; }
.bar > i { display: block; height: 100%; background: repeating-linear-gradient(35deg, var(--teal) 0 4px, #35b5af 4px 8px); transition: width 300ms; }
.bar.orange > i { background: repeating-linear-gradient(35deg, var(--orange) 0 4px, #f8b833 4px 8px); }
.chip { display: inline-block; font-family: var(--font-hand); font-size: 1rem; padding: 2px 10px; border: 2px solid var(--graphite); border-radius: var(--wobble); background: #fff; margin: 2px; }
.chip.direct { border-color: var(--green); color: var(--green); } .chip.small { border-color: var(--orange); color: #b57a00; } .chip.big { border-color: var(--blue); color: var(--blue); } .chip.combo { border-color: var(--purple); color: var(--purple); }
.stat-row { display: flex; gap: 14px; flex-wrap: wrap; }
.stat { flex: 1 1 140px; text-align: center; padding: 10px; }
.stat b { display: block; font-family: var(--font-hand); font-size: 2.1rem; line-height: 1; }
.stat span { font-size: 0.85rem; color: var(--ink-soft); }

/* lessons */
.lesson-list { list-style: none; padding: 0; margin: 0; }
.lesson-list li { display: flex; align-items: center; gap: 12px; padding: 10px 6px; border-bottom: 1.5px dashed rgba(60,60,80,0.25); }
.lesson-list li:last-child { border-bottom: 0; }
.lesson-list .ix { width: 34px; height: 34px; border-radius: 50%; border: 2px solid var(--graphite); display: grid; place-items: center; font-family: var(--font-hand); font-size: 1.15rem; background: #fff; flex: none; }
.lesson-list li.done .ix { background: var(--green); color: #fff; border-color: var(--green); }
.lesson-list a { text-decoration: none; color: inherit; font-weight: 700; }
.lesson-list .meta { font-size: 0.85rem; color: var(--ink-soft); }

.formula-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(190px, 1fr)); gap: 8px; }
.formula { padding: 8px 12px; border: 2px solid var(--graphite); border-radius: var(--wobble); background: #fff; font-family: var(--font-hand); font-size: 1.25rem; text-align: center; }
.formula small { display: block; font-family: var(--font-body); font-size: 0.78rem; color: var(--ink-soft); }
.formula.small { border-color: var(--orange); } .formula.big { border-color: var(--blue); } .formula.combo { border-color: var(--purple); }

/* drill */
.drill { text-align: center; }
.drill .problem { font-family: var(--font-hand); font-size: 2.6rem; line-height: 1.2; margin: 10px 0; color: var(--graphite); }
.drill .problem.stack { display: inline-block; text-align: right; }
.drill .problem.stack div { padding: 0 6px; }
.drill .problem.stack div:last-child { border-top: 3px solid var(--graphite); }
.drill input[type=number], .drill input[type=text] { font-family: var(--font-hand); font-size: 2.2rem; width: 220px; max-width: 80vw; text-align: center; padding: 6px 10px; border: 2.5px solid var(--graphite); border-radius: var(--wobble2); background: #fff; outline: none; }
.drill input:focus { border-color: var(--teal); }
.feedback { font-family: var(--font-hand); font-size: 1.6rem; min-height: 1.8em; margin: 8px 0; }
.feedback.good { color: var(--green); } .feedback.bad { color: var(--red); }
.drill .hud { display: flex; justify-content: center; gap: 18px; flex-wrap: wrap; font-family: var(--font-hand); font-size: 1.2rem; color: var(--ink-soft); }
.drill .hud b { color: var(--graphite); font-size: 1.5rem; }
.timer { font-family: var(--font-hand); font-size: 1.5rem; }

/* flash */
.flash-stage { height: 220px; display: grid; place-items: center; border: 2.5px dashed var(--graphite); border-radius: var(--wobble); background: #fff; margin: 10px 0; }
.flash-stage .num { font-family: var(--font-hand); font-size: 6rem; color: var(--graphite); }
.flash-stage .num.neg { color: var(--red); }
.flash-stage .ready { font-family: var(--font-hand); font-size: 2rem; color: var(--ink-soft); }

/* ranking chart */
.rank-chart { width: 100%; height: auto; }
.rank-chart text { font-family: var(--font-body); font-size: 12px; fill: var(--ink-soft); }
.rank-chart .hand { font-family: var(--font-hand); font-size: 15px; fill: var(--graphite); }
.table { width: 100%; border-collapse: collapse; font-size: 0.95rem; }
.table th, .table td { text-align: left; padding: 8px 10px; border-bottom: 1.5px dashed rgba(60,60,80,0.25); vertical-align: top; }
.table th { font-family: var(--font-hand); font-size: 1.15rem; font-weight: 400; }
.table tr.me { background: rgba(247,209,84,0.35); }

/* misc */
.two-col { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
@media (max-width: 760px) { .two-col { grid-template-columns: 1fr; } }
.callout { border-left: 5px solid var(--orange); background: rgba(243,167,18,0.12); padding: 10px 14px; border-radius: 0 12px 12px 0; margin: 12px 0; }
.callout.science { border-color: var(--purple); background: rgba(142,94,162,0.1); }
.callout.parent { border-color: var(--teal); background: rgba(41,161,156,0.1); }
.callout.warn { border-color: var(--red); background: rgba(228,87,46,0.1); }
.callout b.lbl { font-family: var(--font-hand); font-size: 1.15rem; display: block; margin-bottom: 2px; }
details { margin: 8px 0; }
summary { cursor: pointer; font-family: var(--font-hand); font-size: 1.2rem; }
.badge-xp { display: inline-flex; align-items: center; gap: 6px; font-family: var(--font-hand); font-size: 1.1rem; padding: 3px 10px; border-radius: 20px; background: var(--yellow); border: 2px solid var(--graphite); }
.sticker { position: absolute; top: -14px; right: 16px; transform: rotate(6deg); background: var(--pink); color: #fff; font-family: var(--font-hand); padding: 2px 12px; border-radius: var(--wobble); border: 2px solid var(--graphite); }
.profile-row { display: flex; gap: 8px; flex-wrap: wrap; align-items: center; }
.profile-row select, .profile-row input { font-family: var(--font-hand); font-size: 1.1rem; padding: 6px 10px; border: 2px solid var(--graphite); border-radius: var(--wobble); background: #fff; }
.kbd { font-family: var(--font-body); font-size: 0.8rem; border: 1.5px solid var(--graphite); border-bottom-width: 3px; border-radius: 6px; padding: 0 6px; background: #fff; }
.toast { position: fixed; left: 50%; bottom: 24px; transform: translateX(-50%); background: var(--graphite); color: #fff; font-family: var(--font-hand); font-size: 1.3rem; padding: 10px 20px; border-radius: var(--wobble); z-index: 50; animation: pop 200ms ease-out; box-shadow: var(--shadow); }
@keyframes pop { from { transform: translateX(-50%) scale(0.8); opacity: 0; } to { transform: translateX(-50%) scale(1); opacity: 1; } }
.confetti { position: fixed; inset: 0; pointer-events: none; z-index: 60; }
.hero { display: grid; grid-template-columns: 1.2fr 1fr; gap: 22px; align-items: center; }
@media (max-width: 760px) { .hero { grid-template-columns: 1fr; } }
.hero h1 { font-size: 3rem; }
.hero h1 .line { display: block; }
.steps-row { display: grid; grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); gap: 12px; }
.steps-row .card { margin: 0; }
.steps-row .n { font-family: var(--font-hand); font-size: 2rem; color: var(--orange); line-height: 1; }
.footer { margin-top: 40px; color: var(--ink-soft); font-size: 0.85rem; text-align: center; }
.print-only { display: none; }
@media print { .nav, .topbar .btn, .holes, .btn-row { display: none !important; } body { background: #fff; } .wrap { padding: 0; } .card { break-inside: avoid; } .print-only { display: block; } }