:root {
  --bg: #fff8f0;
  --paper: #ffffff;
  --ink: #221b33;
  --ink-2: #5d5470;
  --line: rgba(34, 27, 51, 0.1);
  --coral: #ff6b4a;
  --coral-d: #e2502f;
  --sun: #ffc23d;
  --teal: #1fa595;
  --violet: #7b5cff;
  --pink: #ff7ab6;
  --radius: 26px;
  --shadow: 0 1px 2px rgba(34, 27, 51, 0.06), 0 12px 32px -12px rgba(34, 27, 51, 0.18);
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --head: "Rubik", "Heebo", system-ui, sans-serif;
  --body: "Heebo", "Rubik", system-ui, sans-serif;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 84px; }
body { margin: 0; background: var(--bg); color: var(--ink); font: 400 17px/1.7 var(--body); -webkit-font-smoothing: antialiased; overflow-x: hidden; }
img { max-width: 100%; display: block; }
a { color: inherit; }
h1, h2, h3 { font-family: var(--head); line-height: 1.1; margin: 0; letter-spacing: -0.02em; text-wrap: balance; }
p, li { text-wrap: pretty; }
h2 { font-size: clamp(30px, 4.4vw, 48px); font-weight: 800; letter-spacing: -0.025em; line-height: 1.08; }
h3 { font-size: 20px; font-weight: 700; letter-spacing: -0.01em; }
p { margin: 0 0 14px; }
.wrap { width: min(1160px, 100% - 32px); margin-inline: auto; }
.muted { color: var(--ink-2); }
.sr { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); }
.skip { position: absolute; top: -40px; right: 16px; background: var(--ink); color: #fff; padding: 8px 14px; border-radius: 10px; z-index: 100; }
.skip:focus { top: 10px; }
:focus-visible { outline: 3px solid var(--violet); outline-offset: 3px; border-radius: 8px; }

/* buttons */
.btn { position: relative; isolation: isolate; overflow: hidden; display: inline-flex; align-items: center; justify-content: center; gap: 8px; height: 52px; padding: 0 26px; border-radius: 999px; border: 0; font: 600 17px var(--head); letter-spacing: 0.005em; text-decoration: none; cursor: pointer; white-space: nowrap; }
/* 3D on hover (pointer only): the element tilts toward the pointer 1:1, lifts, and a soft sheen follows
   it; it settles back on a critically damped curve when the pointer leaves. Touch gets the press-scale. */
.tilt { transform: perspective(var(--persp, 900px)) translateY(var(--lift, 0px)) rotateX(var(--rx, 0deg)) rotateY(var(--ry, 0deg)) scale(var(--press, 1)); transition: transform 520ms var(--ease), box-shadow 520ms var(--ease), background 200ms; will-change: transform; }
.tilt::after { content: ""; position: absolute; inset: 0; z-index: 3; border-radius: inherit; pointer-events: none; background: radial-gradient(55% 55% at var(--mx, 50%) var(--my, 0%), rgba(255, 255, 255, 0.55), transparent 70%); mix-blend-mode: soft-light; opacity: 0; transition: opacity 400ms ease; }
@media (hover: hover) and (pointer: fine) {
  .tilt:hover { --lift: -4px; }
  .tilt:hover::after { opacity: 1; }
  .tilt.tracking { transition: transform 60ms linear, box-shadow 520ms var(--ease), background 200ms; }
  .btn.tilt:hover { --lift: -3px; }
  .btn-primary.tilt:hover { box-shadow: 0 2px 0 var(--coral-d), 0 18px 30px -12px rgba(255, 107, 74, 0.9); }
  .btn-ink.tilt:hover, .btn-ghost.tilt:hover { box-shadow: 0 16px 28px -14px rgba(34, 27, 51, 0.55), inset 0 0 0 2px var(--ink); }
}
.tilt:active { --press: 0.97; transition-duration: 90ms; }
.btn-primary { background: var(--coral); color: #fff; box-shadow: 0 10px 24px -10px rgba(255, 107, 74, 0.8); }
.btn-primary:hover { background: var(--coral-d); }
.btn-ghost { background: transparent; color: var(--ink); box-shadow: inset 0 0 0 2px var(--line); }
.btn-ghost:hover { box-shadow: inset 0 0 0 2px var(--ink); }
.btn-ghost.tilt, .btn-ink.tilt { --persp: 600px; }
.btn.tilt { --persp: 500px; }
.btn-ink { background: var(--ink); color: #fff; }
.btn-sm { height: 40px; padding: 0 18px; font-size: 15px; }

/* header */
.top { position: sticky; top: 0; z-index: 50; background: rgba(255, 248, 240, 0.72); backdrop-filter: saturate(180%) blur(18px); -webkit-backdrop-filter: saturate(180%) blur(18px); }
/* scroll edge: a soft fade where content slides under the bar, only once it does */
.top::after { content: ""; position: absolute; inset: 100% 0 auto; height: 18px; pointer-events: none; background: linear-gradient(rgba(34, 27, 51, 0.07), rgba(34, 27, 51, 0)); opacity: 0; transition: opacity 250ms; }
.top.scrolled::after { opacity: 1; }
.top-in { display: flex; align-items: center; gap: 24px; height: 72px; }
.brand { display: flex; align-items: center; gap: 12px; text-decoration: none; }
.brand-mark { position: relative; width: 38px; height: 38px; }
.brand-mark i { position: absolute; width: 22px; height: 22px; border-radius: 50%; mix-blend-mode: multiply; }
.brand-mark i:nth-child(1) { background: var(--coral); top: 0; right: 0; }
.brand-mark i:nth-child(2) { background: var(--sun); bottom: 0; right: 8px; }
.brand-mark i:nth-child(3) { background: var(--teal); top: 6px; left: 0; }
.brand-text { display: grid; line-height: 1.1; }
.brand-text b { font: 800 21px var(--head); letter-spacing: -0.01em; }
.brand-text small { font-size: 12.5px; color: var(--ink-2); font-weight: 500; }
.nav { display: flex; gap: 4px; margin-inline-start: auto; }
.nav a { padding: 8px 14px; border-radius: 999px; text-decoration: none; font: 500 16px var(--head); color: var(--ink-2); transition: color 150ms, background 150ms; }
.nav a:hover { color: var(--ink); background: rgba(34, 27, 51, 0.05); }
.menu-btn { display: none; width: 44px; height: 44px; border: 0; background: none; cursor: pointer; padding: 10px; }
.menu-btn span { display: block; height: 2.5px; background: var(--ink); border-radius: 2px; margin: 6px 0; transition: transform 250ms var(--ease); }
.menu-btn[aria-expanded="true"] span:first-child { transform: translateY(4.25px) rotate(45deg); }
.menu-btn[aria-expanded="true"] span:last-child { transform: translateY(-4.25px) rotate(-45deg); }

/* hero */
.hero { position: relative; padding: clamp(32px, 6vw, 72px) 0 clamp(40px, 6vw, 80px); overflow: hidden; }
.hero::before { content: ""; position: absolute; inset: -20% -10% auto auto; width: 70vw; height: 70vw; max-width: 900px; max-height: 900px; background: radial-gradient(closest-side, rgba(255, 194, 61, 0.35), transparent 70%); pointer-events: none; }
.hero::after { content: ""; position: absolute; inset: auto auto -30% -20%; width: 60vw; height: 60vw; max-width: 800px; max-height: 800px; background: radial-gradient(closest-side, rgba(31, 165, 149, 0.18), transparent 70%); pointer-events: none; }
.hero-in { position: relative; z-index: 1; display: grid; grid-template-columns: 1.05fr 1fr; gap: clamp(24px, 5vw, 64px); align-items: center; }
.eyebrow { display: inline-flex; align-items: center; gap: 10px; padding: 6px 14px; border-radius: 999px; background: var(--paper); box-shadow: var(--shadow); font: 500 14px var(--head); color: var(--ink-2); }
.eyebrow .dot { width: 8px; height: 8px; border-radius: 50%; background: var(--teal); box-shadow: 0 0 0 4px rgba(31, 165, 149, 0.18); }
.hero h1 { margin: 18px 0 18px; font-size: clamp(48px, 8vw, 96px); font-weight: 800; letter-spacing: -0.035em; line-height: 0.98; }
.hero h1 em { font-style: normal; background: linear-gradient(90deg, var(--coral), var(--violet)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.lead { font-size: clamp(18px, 1.6vw, 20px); color: var(--ink-2); max-width: 34em; }
.hero-cta { display: flex; gap: 12px; flex-wrap: wrap; margin: 26px 0 30px; }
.hero-stats { list-style: none; padding: 0; margin: 0; display: flex; gap: clamp(18px, 4vw, 40px); }
.hero-stats li { display: grid; }
.hero-stats b { font: 800 34px/1 var(--head); letter-spacing: -0.02em; }
.hero-stats span { font-size: 14px; color: var(--ink-2); }
.hero-art { position: relative; aspect-ratio: 1 / 1.02; max-width: 520px; justify-self: center; width: 100%; }
.blob { position: absolute; inset: 8% 10% 8% 6%; border-radius: 46% 54% 42% 58% / 52% 44% 56% 48%; overflow: hidden; box-shadow: 0 30px 60px -24px rgba(34, 27, 51, 0.4); background: var(--sun); translate: calc(var(--px, 0) * 6px) calc(var(--py, 0) * 6px); }
.blob img { width: 100%; height: 100%; object-fit: cover; }
.float { position: absolute; border-radius: 18px; overflow: hidden; background: var(--paper); box-shadow: 0 18px 40px -16px rgba(34, 27, 51, 0.45); border: 6px solid #fff; }
.float svg { width: 100%; height: 100%; display: block; }
.f1 { width: 38%; aspect-ratio: 4 / 3; top: 2%; left: -2%; rotate: -8deg; translate: calc(var(--px, 0) * -22px) calc(var(--py, 0) * -18px); }
.f2 { width: 34%; aspect-ratio: 4 / 3; bottom: 4%; left: 4%; rotate: 6deg; translate: calc(var(--px, 0) * -14px) calc(var(--py, 0) * -12px); }
.f3 { width: 30%; aspect-ratio: 4 / 3; bottom: 16%; right: -4%; rotate: -4deg; translate: calc(var(--px, 0) * -30px) calc(var(--py, 0) * -24px); }
.splash { position: absolute; border-radius: 50%; mix-blend-mode: multiply; }
.s1 { width: 70px; height: 70px; background: var(--coral); top: 4%; right: 8%; opacity: 0.85; translate: calc(var(--px, 0) * 34px) calc(var(--py, 0) * 28px); }
.s2 { width: 34px; height: 34px; background: var(--teal); top: 30%; right: 0; translate: calc(var(--px, 0) * 44px) calc(var(--py, 0) * 36px); }
.s3 { width: 22px; height: 22px; background: var(--violet); bottom: 6%; right: 36%; }

/* sections */
.section { padding: clamp(56px, 8vw, 104px) 0; }
.head { max-width: 640px; margin-bottom: 36px; }
.kicker { font: 600 15px var(--head); color: var(--coral); margin-bottom: 10px; letter-spacing: 0.015em; }
.ticks { list-style: none; padding: 0; margin: 18px 0 26px; display: grid; gap: 10px; }
.ticks li { position: relative; padding-inline-start: 34px; }
.ticks li::before { content: ""; position: absolute; right: 0; top: 4px; width: 22px; height: 22px; border-radius: 50%; background: rgba(31, 165, 149, 0.15) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M6 12.5l4 4 8-9' fill='none' stroke='%231fa595' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E") center / 14px no-repeat; }

/* save */
.save { padding-top: 0; }
.save-end { padding-top: 0; }
.save-card { display: grid; grid-template-columns: 1.2fr 1fr; gap: clamp(24px, 4vw, 56px); padding: clamp(26px, 4vw, 52px); border-radius: 34px; background: var(--ink); color: #fff; position: relative; overflow: hidden; }
.save-card::after { content: ""; position: absolute; width: 380px; height: 380px; left: -120px; bottom: -180px; border-radius: 50%; background: radial-gradient(closest-side, rgba(123, 92, 255, 0.55), transparent); pointer-events: none; }
.save-card .muted { color: rgba(255, 255, 255, 0.72); }
.save-card .kicker { color: var(--sun); }
.save-card .ticks li::before { background-color: rgba(255, 194, 61, 0.18); background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M6 12.5l4 4 8-9' fill='none' stroke='%23ffc23d' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E"); }
.weekly { position: relative; z-index: 1; display: grid; gap: 14px; align-content: start; padding: 26px; border-radius: 24px; background: rgba(255, 255, 255, 0.08); border: 1px solid rgba(255, 255, 255, 0.14); }
.weekly h3 { margin-bottom: 4px; }
label { display: grid; gap: 6px; font: 500 14px var(--head); }
input, textarea { width: 100%; font: 400 17px var(--body); padding: 13px 16px; border-radius: 14px; border: 1.5px solid var(--line); background: var(--paper); color: var(--ink); transition: border-color 150ms, box-shadow 150ms; }
input:focus, textarea:focus { outline: none; border-color: var(--violet); box-shadow: 0 0 0 4px rgba(123, 92, 255, 0.16); }
.weekly input { background: rgba(255, 255, 255, 0.95); border-color: transparent; }
.form-msg { min-height: 1.4em; margin: 0; font-size: 15px; }
.form-msg.ok { color: var(--teal); }
.weekly .form-msg.ok { color: var(--sun); }
.form-msg.err { color: var(--coral-d); }

/* kits */
.kits { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.kit { position: relative; isolation: isolate; display: grid; grid-template-rows: auto 1fr; border-radius: var(--radius); background: var(--paper); box-shadow: var(--shadow); overflow: hidden; text-align: start; border: 0; padding: 0; font: inherit; color: inherit; cursor: pointer; --persp: 1100px; }
@media (hover: hover) and (pointer: fine) { .kit:hover, .lesson:hover, .values li:hover { box-shadow: 0 2px 6px rgba(34, 27, 51, 0.05), 0 26px 50px -16px rgba(34, 27, 51, 0.32); } .kit:hover .kit-art :is(svg, img), .lesson:hover .lesson-art :is(svg, img) { transform: scale(1.05); } }
.kit-art :is(svg, img), .lesson-art :is(svg, img) { transition: transform 700ms var(--ease); }
.kit-art { aspect-ratio: 4 / 3; position: relative; }
.kit-art svg { width: 100%; height: 100%; display: block; }
.kit-badge { position: absolute; top: 14px; right: 14px; padding: 4px 12px; border-radius: 999px; background: rgba(255, 255, 255, 0.92); font: 600 13px var(--head); backdrop-filter: blur(6px); }
.kit-body { padding: 18px 20px 20px; display: grid; gap: 6px; align-content: start; }
.kit-body p { margin: 0; color: var(--ink-2); font-size: 15px; }
.kit-meta { display: flex; gap: 6px; flex-wrap: wrap; margin-top: 8px; }
.chip { display: inline-flex; align-items: center; height: 28px; padding: 0 11px; border-radius: 999px; background: #f4efe8; font: 500 13px var(--head); letter-spacing: 0.01em; color: var(--ink-2); }
.kit-go { margin-top: 10px; font: 600 15px var(--head); color: var(--coral); }

/* approach */
.approach { background: linear-gradient(180deg, transparent, rgba(255, 194, 61, 0.12) 30%, rgba(255, 194, 61, 0.12) 70%, transparent); }
.approach-in { display: grid; grid-template-columns: 1.1fr 1fr; gap: clamp(28px, 5vw, 72px); align-items: center; }
.approach p { color: var(--ink-2); max-width: 36em; }
.approach h2 { margin-bottom: 18px; }
.values { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.values li { position: relative; isolation: isolate; display: grid; gap: 2px; padding: 22px; border-radius: 22px; background: var(--paper); box-shadow: var(--shadow); --persp: 700px; }
.values b { font: 700 19px var(--head); }
.values small { color: var(--ink-2); font-size: 14.5px; }
.v-ico { width: 44px; height: 44px; display: grid; place-items: center; border-radius: 14px; font-size: 22px; margin-bottom: 10px; }
.values li:nth-child(1) .v-ico { background: rgba(255, 107, 74, 0.14); color: var(--coral); }
.values li:nth-child(2) .v-ico { background: rgba(31, 165, 149, 0.14); color: var(--teal); }
.values li:nth-child(3) .v-ico { background: rgba(123, 92, 255, 0.14); color: var(--violet); }
.values li:nth-child(4) .v-ico { background: rgba(255, 194, 61, 0.24); color: #b07a00; }

/* book */
.book-in { display: grid; grid-template-columns: 1fr 1.1fr; gap: clamp(28px, 6vw, 88px); align-items: center; }
.book-visual { display: grid; place-items: center; perspective: 1400px; padding: 20px; }
.book3d { position: relative; width: min(320px, 70vw); aspect-ratio: 3 / 4; transform: rotateY(-24deg) rotateX(6deg); transform-style: preserve-3d; transition: transform 700ms var(--ease); }
.book-visual:hover .book3d { transform: rotateY(-10deg) rotateX(3deg); }
.cover { position: absolute; inset: 0; border-radius: 6px 16px 16px 6px; overflow: hidden; box-shadow: 24px 30px 50px -20px rgba(34, 27, 51, 0.55), inset 6px 0 10px rgba(0, 0, 0, 0.15); transform: translateZ(14px); background: var(--paper); }
.cover svg { position: absolute; inset: 0; width: 100%; height: 100%; }
.cover-title { position: absolute; inset: auto 0 0; padding: 26px 24px; background: linear-gradient(0deg, rgba(34, 27, 51, 0.88), rgba(34, 27, 51, 0)); color: #fff; display: grid; gap: 2px; }
.cover-title small { font: 600 14px var(--head); opacity: 0.85; }
.cover-title b { font: 800 44px/0.95 var(--head); letter-spacing: -0.02em; }
.cover-title span { margin-top: 8px; font: 500 15px var(--head); opacity: 0.85; }
.pages { position: absolute; inset: 3px 0 3px auto; width: 28px; transform: rotateY(90deg) translateZ(-14px) translateX(14px); transform-origin: right; background: repeating-linear-gradient(90deg, #fff 0 2px, #ece6dc 2px 3px); border-radius: 2px; }

/* about */
.about-in { display: grid; grid-template-columns: 0.9fr 1.1fr; gap: clamp(28px, 6vw, 80px); align-items: center; }
.about-photo { position: relative; max-width: 420px; justify-self: center; width: 100%; }
.about-photo img { width: 100%; aspect-ratio: 1; object-fit: cover; border-radius: 36px; box-shadow: var(--shadow); }
.about-art { position: absolute; width: 46%; aspect-ratio: 4 / 3; left: -8%; bottom: -8%; border-radius: 18px; overflow: hidden; border: 6px solid #fff; box-shadow: 0 18px 40px -16px rgba(34, 27, 51, 0.45); rotate: -6deg; }
.about-art svg { width: 100%; height: 100%; display: block; }
.about p { color: var(--ink-2); max-width: 36em; }
.about h2 { margin-bottom: 16px; }

/* lessons */
.lesson-tools { display: flex; gap: 14px; align-items: center; justify-content: space-between; flex-wrap: wrap; margin-bottom: 24px; }
.grade-tabs { position: relative; display: inline-flex; gap: 4px; padding: 5px; border-radius: 999px; background: #f1ebe2; }
.grade-tabs .thumb { position: absolute; top: 5px; bottom: 5px; left: 0; width: 0; border-radius: 999px; background: var(--paper); box-shadow: 0 2px 8px rgba(34, 27, 51, 0.12); pointer-events: none; }
.grade-tabs button { position: relative; z-index: 1; min-width: 52px; height: 40px; padding: 0 14px; border: 0; border-radius: 999px; background: transparent; font: 600 16px var(--head); color: var(--ink-2); cursor: pointer; transition: color 200ms; }
.grade-tabs button[aria-selected="true"] { color: var(--ink); }
.grade-tabs button:active { scale: 0.96; }
.search { flex: 1; max-width: 340px; min-width: 220px; }
.search input { border-radius: 999px; padding-inline-start: 44px; background: var(--paper) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%235d5470' stroke-width='2.2' stroke-linecap='round'%3E%3Ccircle cx='11' cy='11' r='7'/%3E%3Cpath d='M20 20l-4-4'/%3E%3C/svg%3E") right 16px center / 18px no-repeat; }
.lessons { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }
.lesson { position: relative; isolation: isolate; display: grid; grid-template-rows: auto 1fr; border: 0; padding: 0; background: var(--paper); border-radius: 22px; overflow: hidden; box-shadow: var(--shadow); text-align: start; font: inherit; color: inherit; cursor: pointer; animation: rise 380ms var(--ease) both; --persp: 900px; }
.lesson-art { aspect-ratio: 4 / 3; }
.lesson-art svg { width: 100%; height: 100%; display: block; }
.lesson-body { padding: 14px 16px 16px; display: grid; gap: 4px; align-content: start; }
.lesson-body b { font: 700 17px/1.25 var(--head); }
.lesson-body small { color: var(--ink-2); font-size: 14px; }
.lesson-grade { justify-self: start; margin-bottom: 4px; }
@keyframes rise { from { opacity: 0; translate: 0 8px; } }
.more-row { display: flex; justify-content: center; margin-top: 28px; }
.more-row[hidden] { display: none; }
.empty { grid-column: 1 / -1; text-align: center; color: var(--ink-2); padding: 40px 0; }

/* contact */
.contact-in { display: grid; grid-template-columns: 1fr 1.2fr; gap: clamp(24px, 5vw, 64px); padding: clamp(26px, 4vw, 52px); border-radius: 34px; background: var(--paper); box-shadow: var(--shadow); }
.contact-form { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.contact-form .wide, .contact-form .form-msg { grid-column: 1 / -1; }
.contact-form .btn { justify-self: start; }

/* footer */
.foot { padding: 30px 0 calc(30px + env(safe-area-inset-bottom)); color: var(--ink-2); font-size: 14px; }
.foot-in { display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap; border-top: 1px solid var(--line); padding-top: 22px; }
.foot a { text-decoration: none; }

/* sheet (lesson and kit details) */
.sheet { width: min(980px, 100% - 24px); max-height: min(90vh, 900px); padding: 0; border: 0; border-radius: 28px; background: var(--paper); color: var(--ink); box-shadow: 0 40px 100px -30px rgba(34, 27, 51, 0.6); overflow: auto; }
.sheet { transform-origin: 50% 50%; will-change: transform, opacity; overscroll-behavior: contain; }
.sheet::backdrop { background: rgba(34, 27, 51, 0.42); backdrop-filter: blur(6px); -webkit-backdrop-filter: blur(6px); opacity: var(--p, 1); }
.grab { display: none; }
.lead-sm { font-size: 17px; }
.pl-wait { height: 120px; border-radius: 16px; margin-top: 16px; background: linear-gradient(90deg, #f6f1ea, #fbf8f4, #f6f1ea); background-size: 200% 100%; animation: shimmer 1.2s linear infinite; }
@keyframes shimmer { to { background-position: -200% 0; } }
#sheetBody.swap { animation: swapIn 260ms var(--ease); }
@keyframes swapIn { from { opacity: 0; translate: 0 6px; } }
.sheet-x { position: sticky; top: 12px; display: block; margin: 12px auto -50px 12px; z-index: 2; width: 38px; height: 38px; border: 0; border-radius: 50%; background: rgba(255, 255, 255, 0.92); box-shadow: 0 2px 10px rgba(0, 0, 0, 0.15); font-size: 16px; cursor: pointer; }
.sheet-art { aspect-ratio: 16 / 9; }
.sheet-art svg { width: 100%; height: 100%; display: block; }
.sheet-body { padding: 22px clamp(20px, 4vw, 32px) 28px; }
.sheet-body h3 { font-size: 28px; margin: 6px 0 10px; }
.sheet-body p { color: var(--ink-2); }
.sheet-body h4 { margin: 18px 0 8px; font: 600 15px var(--head); }
.gear { display: flex; flex-wrap: wrap; gap: 8px; list-style: none; padding: 0; margin: 0; }
.sheet-actions { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 22px; }
.kit-list { display: grid; gap: 14px; margin-top: 10px; }
.kit-grade { display: grid; gap: 6px; }
.kit-grade > b { font: 600 15px var(--head); color: var(--ink-2); }
.kit-grade div { display: flex; flex-wrap: wrap; gap: 8px; }
.kit-grade button { height: 34px; padding: 0 14px; border-radius: 999px; border: 1.5px solid var(--line); background: var(--paper); font: 500 14px var(--head); color: var(--ink); cursor: pointer; transition: border-color 150ms, background 150ms; }
.kit-grade button:hover { border-color: var(--coral); background: #fff4f0; }

/* responsive */
@media (max-width: 1000px) {
  .lessons { grid-template-columns: repeat(3, 1fr); }
  .kits { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 860px) {
  .nav { position: fixed; inset: 72px 0 auto; flex-direction: column; gap: 0; padding: 8px 16px 18px; background: rgba(255, 248, 240, 0.97); backdrop-filter: blur(16px); border-bottom: 1px solid var(--line); transform: translateY(-8px); opacity: 0; visibility: hidden; transition: opacity 200ms, transform 250ms var(--ease), visibility 0s 250ms; }
  .nav.open { transform: none; opacity: 1; visibility: visible; transition: opacity 200ms, transform 250ms var(--ease); }
  .nav a { padding: 14px 6px; font-size: 18px; border-radius: 0; border-bottom: 1px solid var(--line); }
  .menu-btn { display: block; }
  .top-cta { margin-inline-start: auto; }
  .hero-in, .save-card, .approach-in, .book-in, .about-in, .contact-in { grid-template-columns: 1fr; }
  .hero-art { max-width: 420px; }
  .book-visual { order: -1; }
  .lessons { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 640px) {
  .sheet { width: 100%; max-width: 100%; max-height: 92vh; margin: auto 0 0; border-radius: 28px 28px 0 0; padding-bottom: env(safe-area-inset-bottom); }
  .grab { display: block; position: sticky; top: 0; z-index: 3; height: 22px; margin-bottom: -22px; }
  .grab::before { content: ""; position: absolute; top: 8px; left: 50%; width: 40px; height: 5px; margin-left: -20px; border-radius: 3px; background: rgba(255, 255, 255, 0.85); box-shadow: 0 1px 4px rgba(0, 0, 0, 0.25); }
  .sheet-x { display: none; }
}
@media (max-width: 560px) {
  body { font-size: 16px; }
  .top-cta { display: none; }
  .menu-btn { margin-inline-start: auto; }
  .kits { grid-template-columns: 1fr; }
  .lessons { grid-template-columns: 1fr 1fr; gap: 12px; }
  .lesson-body { padding: 12px; }
  .lesson-body b { font-size: 15px; }
  .contact-form { grid-template-columns: 1fr; }
  .hero-cta .btn { flex: 1; }
  .grade-tabs { width: 100%; justify-content: space-between; }
  .grade-tabs button { min-width: 0; flex: 1; padding: 0; }
  .search { max-width: none; }
  .values { grid-template-columns: 1fr 1fr; }
  .values li { padding: 16px; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition-duration: 1ms !important; }
  html { scroll-behavior: auto; }
}

@media (prefers-reduced-transparency: reduce) {
  .top { background: var(--bg); backdrop-filter: none; -webkit-backdrop-filter: none; }
  .sheet::backdrop { background: rgba(34, 27, 51, 0.7); backdrop-filter: none; }
  .kit-badge { background: #fff; backdrop-filter: none; }
}
@media (prefers-contrast: more) {
  :root { --ink-2: #3a3350; --line: rgba(34, 27, 51, 0.45); }
  .kit, .lesson, .values li, .contact-in, .weekly { box-shadow: none; outline: 1.5px solid var(--line); }
  .btn-ghost { box-shadow: inset 0 0 0 2px var(--ink); }
}
.field-hint { min-height: 0; color: var(--coral-d); font: 500 13px var(--head); }
.weekly .field-hint { color: var(--sun); }
input[aria-invalid="true"] { border-color: var(--coral); }

/* real photos (when they exist) take the illustrations' places */
.photo { width: 100%; height: 100%; object-fit: cover; display: block; }
.photo-slot { border-radius: 22px; overflow: hidden; aspect-ratio: 4 / 3; box-shadow: var(--shadow); }
.photo-slot[hidden] { display: none; }
.weekly .photo-slot { aspect-ratio: 16 / 9; border-radius: 16px; box-shadow: none; }
.contact .photo-slot { margin-top: 18px; max-width: 420px; }
.wide-slot { aspect-ratio: 21 / 9; margin-bottom: 20px; }
.approach .wide-slot { grid-column: 1 / -1; order: -1; }
.book-visual { position: relative; }
/* with a real photo of the printed book, the photo takes the drawn book's place */
.book-photo { width: 100%; max-width: 520px; aspect-ratio: 4 / 3; rotate: -2deg; border: 8px solid #fff; box-shadow: 0 30px 60px -24px rgba(34, 27, 51, 0.45); }
.book-photo:not([hidden]) + .book3d { display: none; }
@media (max-width: 860px) { .approach .wide-slot { order: 0; } }
/* the section right after the hero doesn't need its full top padding: the hero already leaves room */
.hero { padding-bottom: clamp(24px, 3vw, 40px); }
.hero + .section { padding-top: clamp(16px, 2.5vw, 32px); }

/* contact form, Apple-style: soft filled fields of one height, the label above, a quiet focus ring */
.contact-in { align-items: center; }
.contact-form { gap: 18px 16px; align-content: center; }
.contact-form label { position: relative; display: grid; grid-template-rows: auto auto; gap: 8px; align-content: start; font: 500 14px var(--head); color: var(--ink-2); letter-spacing: 0.01em; }
.contact-form input, .contact-form textarea { height: 52px; padding: 0 16px; border: 0; border-radius: 14px; background: #f4f1ec; font: 400 17px var(--body); color: var(--ink); box-shadow: inset 0 0 0 1px rgba(34, 27, 51, 0.04); transition: background 200ms, box-shadow 200ms; }
.contact-form textarea { height: auto; min-height: 140px; padding: 14px 16px; resize: vertical; line-height: 1.6; }
.contact-form input:hover, .contact-form textarea:hover { background: #efebe5; }
.contact-form input:focus, .contact-form textarea:focus { background: #fff; box-shadow: 0 0 0 1.5px var(--violet), 0 0 0 5px rgba(123, 92, 255, 0.14); }
.contact-form .field-hint { position: absolute; top: calc(100% + 4px); inset-inline-start: 4px; font-size: 12.5px; }
.contact-form .btn { justify-self: stretch; height: 54px; }
.contact-form .form-msg { text-align: center; min-height: 1.2em; }
@media (min-width: 861px) { .contact-form .btn { justify-self: start; min-width: 200px; } }

/* the detail sheet uses the extra room on wide screens: the plan in two columns */
@media (min-width: 900px) {
  .sheet .pl-body { column-count: 2; column-gap: 40px; }
  .sheet .pl-body > .pl-meta { column-span: all; }
  .sheet .pl-sec { break-inside: avoid; margin-top: 0; padding-top: 16px; }
  .sheet-art { aspect-ratio: 21 / 8; }
}
.crumbs a { text-decoration: none; } .crumbs a:hover { text-decoration: underline; }

/* holidays on the home page */
.holiday-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(180px, 1fr)); gap: 16px; }
.holiday { position: relative; isolation: isolate; display: grid; grid-template-rows: auto 1fr; border-radius: 22px; overflow: hidden; background: var(--paper); box-shadow: var(--shadow); text-decoration: none; color: inherit; --persp: 800px; }
.holiday-art { aspect-ratio: 1; overflow: hidden; }
.holiday-art :is(svg, img) { width: 100%; height: 100%; display: block; object-fit: cover; transition: transform 700ms var(--ease); }
.holiday-body { display: grid; gap: 2px; padding: 12px 14px 14px; }
.holiday-body small { color: var(--coral); font: 600 12.5px var(--head); letter-spacing: 0.02em; }
.holiday-body b { font: 700 18px var(--head); }
.holiday-body span { color: var(--ink-2); font-size: 13.5px; }
@media (hover: hover) and (pointer: fine) { .holiday:hover .holiday-art :is(svg, img) { transform: scale(1.06); } .holiday:hover { box-shadow: 0 2px 6px rgba(34, 27, 51, 0.05), 0 26px 50px -16px rgba(34, 27, 51, 0.32); } }
@media (max-width: 560px) { .holiday-grid { grid-template-columns: 1fr 1fr; gap: 12px; } }