@import url('https://fonts.googleapis.com/css2?family=DM+Mono:wght@400;500&family=Manrope:wght@400;500;600;700;800&display=swap');

:root {
	color-scheme: dark;
	--ink: #f4f7fb;
	--muted: #a4afbf;
	--base: #080d15;
	--panel: #111a28;
	--panel-raised: #172235;
	--line: #29364a;
	--lime: #4ade80;
	--coral: #22c55e;
	--cyan: #60a5fa;
	--violet: #94a3b8;
	--mono: 'DM Mono', 'Courier New', monospace;
	--sans: 'Manrope', 'Segoe UI', sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 85px; }
body { margin: 0; background: var(--base); color: var(--ink); font-family: var(--sans); font-size: 14px; }
button, textarea { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
a { color: inherit; text-decoration: none; }
button:focus-visible, a:focus-visible, textarea:focus-visible { outline: 2px solid var(--lime); outline-offset: 4px; }
.scroll-progress { position: fixed; z-index: 20; inset: 0 0 auto; height: 3px; background: transparent; pointer-events: none; }
.scroll-progress span { width: 0; height: 100%; display: block; background: linear-gradient(90deg, var(--cyan), #708aff 48%, var(--violet), var(--lime)); box-shadow: 0 0 13px rgba(98,233,226,.6); transition: width .08s linear; }

.topbar { height: 72px; padding: 0 max(6.5vw, calc((100vw - 1200px) / 2)); display: flex; align-items: center; justify-content: space-between; border-bottom: 1px solid rgba(240, 243, 233, .08); }
.brand { display: inline-flex; align-items: center; gap: 10px; font-size: 14px; font-weight: 800; letter-spacing: 0; }
.brand-mark { width: 31px; height: 31px; display: grid; place-items: center; background: var(--lime); color: #172012; font-family: var(--mono); font-size: 14px; font-weight: 500; transform: rotate(-5deg); }
.brand-dot { color: var(--coral); }
.main-nav { display: flex; align-items: center; gap: 32px; height: 100%; }
.nav-link { height: 100%; display: grid; align-items: center; position: relative; color: var(--muted); font-size: 12px; font-weight: 700; transition: color .2s ease; }
.nav-link:hover, .nav-link.active { color: var(--ink); }
.nav-link.active::after { position: absolute; content: ''; height: 2px; left: 0; right: 0; bottom: -1px; background: var(--lime); }
.theme-toggle, .motion-toggle { min-height: 34px; padding: 0 11px; display: inline-flex; align-items: center; gap: 7px; border: 1px solid var(--line); border-radius: 999px; background: linear-gradient(145deg, var(--panel-raised), var(--panel)); color: var(--ink); box-shadow: 0 3px 0 rgba(0,0,0,.2), 0 7px 14px rgba(0,0,0,.12); font-size: 10px; font-weight: 700; cursor: pointer; transition: transform .18s, box-shadow .18s, background .2s; }
.theme-toggle:hover, .motion-toggle:hover { transform: translateY(-2px); box-shadow: 0 5px 0 rgba(0,0,0,.16), 0 11px 18px rgba(0,0,0,.15); }
.theme-icon { color: var(--lime); font-size: 15px; line-height: 1; }
.motion-icon { color: var(--cyan); font-size: 15px; line-height: 1; }
.top-progress { display: flex; align-items: center; gap: 9px; color: #bdc5bb; font-family: var(--mono); font-size: 11px; }
.status-dot { flex: 0 0 auto; width: 7px; height: 7px; display: inline-block; border-radius: 50%; background: var(--lime); box-shadow: 0 0 11px rgba(196, 244, 107, .55); }
.brand-mark { border-radius: 7px; box-shadow: 0 4px 0 #70952f, 0 8px 18px rgba(196,244,107,.18); }
.topbar { position: relative; z-index: 5; background: color-mix(in srgb, var(--base) 91%, transparent); backdrop-filter: blur(16px); }
.theme-toggle { border-radius: 999px; }

.hero { position: relative; min-height: 490px; max-width: 1200px; margin: auto; padding: 78px 0 70px; display: grid; grid-template-columns: 1fr 1fr; align-items: center; gap: 44px; overflow: hidden; isolation: isolate; }
.hero::before, .hero::after { position: absolute; z-index: -1; content: ''; width: 320px; height: 320px; border-radius: 50%; filter: blur(70px); opacity: .16; pointer-events: none; }
.hero::before { top: 35px; right: 12%; background: var(--cyan); }
.hero::after { right: 1%; bottom: -180px; background: var(--violet); }
.hero-copy { position: relative; z-index: 1; padding-left: 8px; animation: rise-in .7s both; }
.eyebrow { margin: 0 0 22px; color: var(--lime); font-family: var(--mono); font-size: 10px; letter-spacing: 0; }
.eyebrow-line { display: inline-block; width: 22px; height: 1px; margin: 0 8px 3px 0; background: var(--lime); }
h1 { margin: 0; font-size: clamp(54px, 6.2vw, 78px); font-weight: 800; line-height: .98; letter-spacing: 0; }
h1 span { color: var(--cyan); background: linear-gradient(100deg, #76f4d0, #6fd8ff 48%, #b99bff); background-clip: text; -webkit-background-clip: text; -webkit-text-fill-color: transparent; filter: drop-shadow(0 0 23px rgba(98,233,226,.15)); }
.hero-description { max-width: 395px; margin: 22px 0 28px; color: #a7afa6; font-size: 14px; line-height: 1.8; }
.primary-button { width: fit-content; min-height: 45px; padding: 0 18px; display: inline-flex; align-items: center; gap: 22px; border-radius: 5px; background: linear-gradient(110deg, #78f3d9, #bff56c 70%); color: #13231b; box-shadow: 0 5px 0 #558843, 0 12px 24px rgba(98,233,226,.12); font-size: 12px; font-weight: 800; transition: transform .2s, background .2s, box-shadow .2s; }
.primary-button:hover { transform: translateY(-3px); background: linear-gradient(110deg, #a0ffeb, #d6ff88 70%); box-shadow: 0 8px 0 #558843, 0 17px 30px rgba(98,233,226,.18); }
.primary-button span { font-size: 16px; }
.hero-meta { margin-top: 29px; display: flex; align-items: center; gap: 12px; color: var(--muted); font-family: var(--mono); font-size: 10px; }
.meta-icon { width: 24px; height: 24px; display: grid; place-items: center; border: 1px solid #435041; color: var(--lime); }
.meta-divider { height: 13px; width: 1px; background: #414941; }

.hero-art { position: relative; height: 360px; display: grid; place-items: center; perspective: 900px; animation: rise-in .8s .12s both; }
.art-grid { position: absolute; inset: 14px 0; background-image: linear-gradient(rgba(196,244,107,.055) 1px, transparent 1px), linear-gradient(90deg, rgba(196,244,107,.055) 1px, transparent 1px); background-size: 35px 35px; mask-image: radial-gradient(ellipse at center, black 5%, transparent 72%); transform: rotate(-8deg) scale(1.05); }
.orbit { position: absolute; width: 285px; height: 112px; border: 1px solid rgba(196,244,107,.24); border-radius: 50%; transform: rotate(-31deg); }
.orbit-two { width: 320px; height: 150px; border-color: rgba(255,134,103,.18); transform: rotate(38deg); }
.data-cube { position: absolute; z-index: 1; width: 51px; height: 51px; display: grid; place-items: center; border: 1px solid rgba(255,255,255,.4); border-radius: 7px; background: linear-gradient(145deg, #a5e5e2, #48a9a2); color: #163634; box-shadow: inset -8px -8px 14px rgba(14,79,75,.22), 9px 13px 20px rgba(0,0,0,.24); font-family: var(--mono); font-size: 13px; font-weight: 500; transform: perspective(350px) rotateX(-20deg) rotateY(-27deg); animation: data-float 5s ease-in-out infinite; }
.data-cube-one { top: 72px; right: 16%; }
.data-cube-two { bottom: 76px; left: 12%; width: 43px; height: 43px; background: linear-gradient(145deg, #ffc395, #e77e67); color: #4b211c; animation-delay: -2.2s; }
.data-cube { border-radius: 3px; }
.data-cube-one { background: linear-gradient(145deg, #9cf7f0, #46bce0 55%, #5470de); color: #102739; box-shadow: inset -8px -8px 14px rgba(22,44,114,.2), 9px 13px 20px rgba(0,0,0,.24), 0 0 26px rgba(98,233,226,.2); }
.data-cube-two { background: linear-gradient(145deg, #ffd1a0, #fa806d 55%, #dc55b5); box-shadow: inset -8px -8px 14px rgba(119,28,66,.2), 9px 13px 20px rgba(0,0,0,.24), 0 0 24px rgba(255,134,103,.22); }
.data-card { position: absolute; z-index: 1; right: 10%; top: 119px; width: 104px; height: 73px; padding: 8px; border: 1px solid rgba(255,255,255,.2); border-radius: 5px; background: linear-gradient(145deg, rgba(38,51,43,.97), rgba(22,31,26,.97)); box-shadow: 8px 12px 22px rgba(0,0,0,.27); color: #aeb9aa; font-family: var(--mono); font-size: 7px; transform: perspective(500px) rotateY(-15deg) rotateX(7deg); }
.data-card { background: linear-gradient(145deg, rgba(31,47,63,.98), rgba(19,27,42,.98)); border-color: rgba(98,233,226,.35); box-shadow: 8px 12px 22px rgba(0,0,0,.27), 0 0 26px rgba(98,233,226,.12); }
.python-cube, .data-card { transition: translate .18s ease-out; }
.data-card i { width: 8px; margin-right: 5px; display: inline-block; vertical-align: bottom; border-radius: 2px 2px 0 0; background: linear-gradient(#c4f46b, #7dba42); box-shadow: 0 0 8px rgba(196,244,107,.24); }
.data-card i { background: linear-gradient(#62e9e2, #6b83ff); box-shadow: 0 0 9px rgba(98,233,226,.35); }
.data-card i:nth-of-type(1) { height: 16px; }
.data-card i:nth-of-type(2) { height: 25px; }
.data-card i:nth-of-type(3) { height: 20px; }
.data-card i:nth-of-type(4) { height: 34px; }
.data-card b { margin-top: 5px; display: block; color: var(--lime); font-size: 7px; font-weight: 400; }
.data-sparkline { width: 88px; height: 23px; margin: 1px 0 2px; overflow: visible; }
.data-sparkline path { fill: none; stroke: #62e9e2; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; filter: drop-shadow(0 0 3px rgba(98,233,226,.65)); stroke-dasharray: 150; stroke-dashoffset: 150; animation: draw-chart 2.4s .5s ease forwards; }
.data-sparkline circle { fill: #d3ff75; filter: drop-shadow(0 0 4px rgba(211,255,117,.75)); }
.python-cube { position: relative; width: 154px; height: 154px; transform-style: preserve-3d; transform: rotateX(-24deg) rotateY(-36deg); animation: cube-float 6s ease-in-out infinite; }
.cube-face { position: absolute; width: 154px; height: 154px; border: 1px solid rgba(255,255,255,.15); backface-visibility: visible; }
.cube-front { display: grid; place-items: center; background: linear-gradient(145deg, #d5ff81 0%, #a4d746 100%); color: #1c2813; transform: translateZ(77px); box-shadow: inset -12px -12px 30px rgba(34, 68, 11, .13); }
.cube-glyph { font-family: var(--mono); font-size: 53px; font-weight: 500; letter-spacing: 0; transform: translateY(-3px); }
.cube-spark { position: absolute; right: 18px; bottom: 17px; color: #577c26; font-size: 19px; }
.cube-back { background: #395a24; transform: rotateY(180deg) translateZ(77px); }
.cube-right { background: linear-gradient(140deg, #8cbf42, #628f2e); transform: rotateY(90deg) translateZ(77px); }
.cube-left { background: #547a2c; transform: rotateY(-90deg) translateZ(77px); }
.cube-top { background: #e2ffac; transform: rotateX(90deg) translateZ(77px); }
.cube-bottom { background: #658e32; transform: rotateX(-90deg) translateZ(77px); }
.float-label { position: absolute; z-index: 2; padding: 11px 13px; border: 1px solid #39433b; background: rgba(22, 30, 25, .92); color: #dbe3d7; box-shadow: 0 14px 35px rgba(0,0,0,.24); font-family: var(--mono); font-size: 10px; }
.label-top { top: 41px; left: 2%; transform: rotate(-4deg); }
.label-bottom { right: 0; bottom: 43px; display: flex; align-items: center; gap: 9px; transform: rotate(2deg); }
.label-bottom .status-dot { width: 6px; height: 6px; }
.art-index { position: absolute; right: 12px; top: 16px; color: #647064; font-family: var(--mono); font-size: 9px; }

.lesson-section { padding: 63px max(6.5vw, calc((100vw - 1200px) / 2)) 86px; background: linear-gradient(135deg, #151b17, #171c27 55%, #151b17); border-top: 1px solid #202921; border-bottom: 1px solid #202921; }
.section-heading { max-width: 1200px; margin: 0 auto 30px; display: flex; justify-content: space-between; align-items: end; }
.section-heading .eyebrow, .notebook-heading .eyebrow { margin-bottom: 11px; }
h2 { margin: 0; font-size: 27px; font-weight: 700; letter-spacing: 0; }
.heading-dash { padding: 0 7px; color: #697267; }
.section-note { margin: 0 0 4px; color: var(--muted); font-size: 11px; }
.lesson-layout { max-width: 1200px; margin: auto; display: grid; grid-template-columns: 255px minmax(0, 1fr); gap: 22px; align-items: stretch; }
.lesson-list { display: flex; flex-direction: column; border-top: 1px solid var(--line); }
.lesson-item { width: 100%; min-height: 59px; padding: 0 13px; display: grid; grid-template-columns: 36px 1fr 16px; gap: 7px; align-items: center; border: 0; border-bottom: 1px solid var(--line); background: transparent; color: #aeb7ad; text-align: left; cursor: pointer; transition: color .2s, background .2s, padding .2s; }
.lesson-item:hover { padding-left: 18px; color: var(--ink); background: rgba(255,255,255,.025); }
.lesson-item.selected { background: linear-gradient(110deg, #76f3d7, var(--lime)); color: #172012; font-weight: 800; box-shadow: 0 4px 0 #739e3e, 0 9px 16px rgba(98,233,226,.12); }
.lesson-number { font-family: var(--mono); font-size: 10px; opacity: .7; }
.lesson-name { font-size: 12px; }
.lesson-arrow { justify-self: end; font-size: 15px; }
.lesson-item.done:not(.selected) .lesson-arrow { color: var(--lime); }
.lesson-item.done.selected .lesson-arrow { color: #172012; }
.lesson-tip { margin-top: auto; padding: 20px 8px 0; display: flex; align-items: flex-start; gap: 11px; color: #909a90; font-size: 10px; line-height: 1.7; }
.tip-mark { width: 18px; height: 18px; display: grid; place-items: center; border: 1px solid #566050; border-radius: 50%; color: var(--lime); font-family: var(--mono); font-size: 10px; }
.lesson-panel { min-height: 358px; padding: 24px 28px 20px; border: 1px solid #303a31; border-radius: 8px; background: linear-gradient(145deg, var(--panel-raised), var(--panel)); box-shadow: 0 20px 36px rgba(0,0,0,.18), 0 5px 0 rgba(87,111,85,.12); animation: panel-in .25s ease both; }
.panel-topline { display: flex; justify-content: space-between; align-items: center; }
.panel-tag, .panel-time { color: var(--lime); font-family: var(--mono); font-size: 9px; }
.panel-time { color: #7e887d; }
.lesson-panel h3 { margin: 18px 0 8px; font-size: 20px; letter-spacing: 0; }
.lesson-description { max-width: 580px; margin: 0 0 17px; color: #a3ada3; font-size: 11px; line-height: 1.75; }
.code-window { border: 1px solid #303a32; background: #101512; }
.code-header { height: 35px; padding: 0 12px; display: flex; align-items: center; gap: 11px; border-bottom: 1px solid #29322b; color: #8e998e; font-family: var(--mono); font-size: 9px; }
.window-dots { display: flex; gap: 4px; }
.window-dots i { width: 6px; height: 6px; display: block; border-radius: 50%; background: #52604d; }
.window-dots i:first-child { background: var(--coral); }
.window-dots i:nth-child(2) { background: #d5c46b; }
.window-dots i:last-child { background: var(--lime); }
.copy-button { margin-left: auto; padding: 5px 7px; border: 0; background: transparent; color: #adb7ab; font-family: var(--mono); font-size: 9px; cursor: pointer; }
.copy-button:hover { color: var(--lime); }
.copy-button span { margin-left: 4px; }
.code-window pre { min-height: 98px; margin: 0; padding: 12px 15px; color: #d4ded2; font-family: var(--mono); font-size: 11px; line-height: 1.7; white-space: pre-wrap; }
.code-keyword { color: #d3a6ff; }
.code-string { color: var(--lime); }
.code-number { color: #ffac7b; }
.code-function { color: #80d8d0; }
.code-output { min-height: 29px; padding: 6px 12px; display: flex; align-items: center; gap: 8px; border-top: 1px solid #29322b; color: #c1ccc0; font-family: var(--mono); font-size: 10px; white-space: pre-line; }
.output-marker { color: var(--lime); }
.output-label { margin-left: auto; color: #667166; font-size: 8px; }
.panel-footer { margin-top: 16px; display: flex; justify-content: space-between; align-items: center; gap: 14px; }
.panel-footer > span { color: #849084; font-family: var(--mono); font-size: 9px; }
.complete-button { min-height: 34px; padding: 0 12px; display: inline-flex; align-items: center; gap: 12px; border: 1px solid #475343; background: transparent; color: var(--lime); font-size: 10px; font-weight: 700; cursor: pointer; transition: background .2s, color .2s; }
.complete-button:hover { background: var(--lime); color: #172012; }

.notebook-section { max-width: 1200px; margin: auto; padding: 74px 0 82px; }
.notebook-heading { margin-bottom: 25px; display: flex; justify-content: space-between; align-items: center; }
.notebook-workspace { display: grid; grid-template-columns: 230px minmax(0, 1fr); gap: 20px; align-items: start; perspective: 1300px; }
.notes-library { position: relative; padding: 15px 12px 12px; border: 1px solid var(--line); border-radius: 9px; background: linear-gradient(145deg, var(--panel-raised), var(--panel)); box-shadow: 0 15px 28px rgba(0,0,0,.18), 0 4px 0 rgba(98,233,226,.11); }
.library-heading, .library-heading > div { display: flex; align-items: center; }
.library-heading { justify-content: space-between; gap: 8px; padding-bottom: 13px; border-bottom: 1px solid var(--line); }
.library-heading > div { gap: 9px; }
.library-icon { width: 32px; height: 32px; display: grid; place-items: center; border: 1px solid rgba(98,233,226,.3); border-radius: 8px; background: linear-gradient(145deg, #243e48, #222b49); color: var(--cyan); box-shadow: 0 4px 0 rgba(0,0,0,.18); font-size: 17px; }
.library-heading strong, .library-heading small { display: block; }
.library-heading strong { color: var(--ink); font-size: 11px; }
.library-heading small { margin-top: 3px; color: var(--muted); font-family: var(--mono); font-size: 8px; }
.add-note-button { width: 31px; height: 31px; border: 1px solid rgba(98,233,226,.35); border-radius: 7px; background: linear-gradient(145deg, #51e4dd, #7ba1ff); color: #102529; box-shadow: 0 4px 0 #287f94, 0 7px 15px rgba(98,233,226,.2); font-size: 21px; line-height: 1; cursor: pointer; transition: transform .18s, box-shadow .18s; }
.add-note-button:hover { transform: translateY(-2px); box-shadow: 0 6px 0 #287f94, 0 10px 18px rgba(98,233,226,.23); }
.notes-list { max-height: 330px; padding-top: 9px; overflow-y: auto; }
.saved-note { display: flex; align-items: center; gap: 3px; margin: 4px 0; border: 1px solid transparent; border-radius: 6px; transition: background .2s, border-color .2s, transform .2s; }
.saved-note:hover { transform: translateX(2px); background: rgba(98,233,226,.06); }
.saved-note.active { border-color: rgba(98,233,226,.3); background: linear-gradient(120deg, rgba(98,233,226,.12), rgba(170,134,255,.08)); box-shadow: inset 3px 0 var(--cyan); }
.saved-note-open { min-width: 0; flex: 1; padding: 9px 8px; overflow: hidden; border: 0; background: transparent; color: var(--ink); text-align: left; cursor: pointer; }
.saved-note-open strong, .saved-note-open span { display: block; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.saved-note-open strong { font-size: 10px; }
.saved-note-open span { margin-top: 4px; color: var(--muted); font-size: 8px; }
.saved-note-delete { width: 25px; height: 25px; border: 0; border-radius: 5px; background: transparent; color: var(--muted); font-size: 16px; cursor: pointer; }
.saved-note-delete:hover { background: rgba(255,134,103,.13); color: var(--coral); }
.backup-actions { margin-top: 9px; display: grid; grid-template-columns: 1fr 1fr; gap: 6px; }
.backup-action { min-height: 28px; padding: 6px 5px; display: inline-flex; align-items: center; justify-content: center; border: 1px solid rgba(98,233,226,.2); border-radius: 5px; background: rgba(98,233,226,.045); color: var(--muted); font-size: 8px; cursor: pointer; transition: background .18s, border-color .18s, transform .18s; }
.backup-action:hover { transform: translateY(-1px); border-color: rgba(98,233,226,.5); background: rgba(98,233,226,.11); color: var(--ink); }
.backup-action input { position: absolute; width: 1px; height: 1px; overflow: hidden; opacity: 0; pointer-events: none; }
.library-hint { margin: 11px 2px 0; color: var(--muted); font-size: 8px; line-height: 1.6; }
.note-title-input { width: 100%; padding: 12px 17px; border: 0; border-bottom: 1px solid #303a31; outline: 0; background: rgba(98,233,226,.035); color: var(--ink); font-size: 14px; font-weight: 800; }
.note-title-input::placeholder { color: #778477; font-weight: 600; }
.notebook-heading h2 { font-size: 25px; }
.notebook-subtitle { margin: 8px 0 0; color: var(--muted); font-size: 11px; }
.notebook-stamp { padding: 9px 11px; border: 1px solid #596447; color: var(--lime); font-family: var(--mono); font-size: 8px; line-height: 1.7; text-align: center; transform: rotate(4deg); }
.notebook-editor { position: relative; z-index: 0; border: 1px solid #303a31; background: #151b17; box-shadow: 0 25px 55px rgba(0,0,0,.24), 0 8px 16px rgba(0,0,0,.2); transform-style: preserve-3d; transition: transform .3s ease, box-shadow .3s ease; }
.notebook-editor::before, .notebook-editor::after { position: absolute; z-index: -1; content: ''; border: 1px solid #37443a; pointer-events: none; }
.notebook-editor::before { inset: 7px -7px -7px 7px; background: #222c25; transform: translateZ(-8px) rotate(.6deg); }
.notebook-editor::after { inset: 13px -13px -13px 13px; background: #1b241e; transform: translateZ(-16px) rotate(1.2deg); }
.notebook-editor:hover { transform: perspective(1100px) rotateX(.6deg) rotateY(-.35deg) translateY(-2px); box-shadow: 0 32px 65px rgba(0,0,0,.3), 0 12px 20px rgba(0,0,0,.22); }
.editor-toolbar { min-height: 38px; padding: 0 14px; display: flex; justify-content: space-between; align-items: center; gap: 8px; border-bottom: 1px solid #303a31; color: #899488; font-family: var(--mono); font-size: 9px; }
.editor-toolbar > span:first-child { display: flex; align-items: center; gap: 8px; color: #b7c1b4; }
.editor-toolbar .status-dot { width: 6px; height: 6px; }
.editor-toolbar #save-status { color: #879287; }
.format-toolbar { min-height: 48px; padding: 8px 12px; display: flex; flex-wrap: wrap; align-items: center; gap: 10px 20px; border-bottom: 1px solid #303a31; background: linear-gradient(110deg, #1a221c, #202a23 55%, #19211c); }
.format-group { display: flex; flex-wrap: wrap; align-items: center; gap: 5px; }
.format-button { min-width: 29px; height: 27px; padding: 0 7px; border: 1px solid transparent; border-radius: 4px; background: transparent; color: #b9c3b6; font-family: var(--mono); font-size: 10px; cursor: pointer; transition: background .15s, color .15s, transform .15s; }
.format-button:hover, .format-button:focus-visible { border-color: #465448; background: #2a362c; color: var(--lime); transform: translateY(-1px); }
.italic-button { font-family: Georgia, serif; font-size: 13px; }
.underline-button { font-family: Georgia, serif; font-size: 12px; }
.list-button { font-size: 9px; }
.toolbar-divider { width: 1px; height: 19px; margin: 0 3px; background: #39443b; }
.font-size-control { display: flex; align-items: center; gap: 6px; color: #8f9b8e; font-size: 9px; }
.font-size-control select { max-width: 96px; padding: 5px 19px 5px 7px; border: 1px solid #39443b; border-radius: 4px; background: #151b17; color: #c4cec0; font: inherit; cursor: pointer; }
.palette-label { margin: 0 3px 0 1px; color: #7f8a7e; font-family: var(--mono); font-size: 8px; letter-spacing: .04em; }
.color-swatch, .paper-swatch { position: relative; width: 19px; height: 19px; padding: 0; border: 2px solid #303a31; border-radius: 50%; background: var(--swatch); cursor: pointer; transition: transform .15s, border-color .15s; }
.color-swatch:hover, .paper-swatch:hover { transform: translateY(-2px) scale(1.08); }
.color-swatch.selected, .paper-swatch.selected { border-color: var(--lime); box-shadow: 0 0 0 2px rgba(196,244,107,.13); }
.ink-swatch { --swatch: #243128; }
.color-swatch[data-ink="#2878c8"] { --swatch: #2878c8; }
.color-swatch[data-ink="#d84f55"] { --swatch: #d84f55; }
.color-swatch[data-ink="#874db3"] { --swatch: #874db3; }
.paper-swatch { width: 23px; height: 23px; display: grid; place-items: center; border-color: #445046; background: #29332b; }
.paper-swatch span { width: 12px; height: 15px; border-radius: 1px; background: var(--paper-swatch); box-shadow: 1px 2px 2px rgba(0,0,0,.25); }
.paper-swatch[data-paper="cream"] { --paper-swatch: #f0e9ce; }
.paper-swatch[data-paper="blue"] { --paper-swatch: #d9e8f4; }
.paper-swatch[data-paper="pink"] { --paper-swatch: #f3dfe0; }
.paper-swatch[data-paper="green"] { --paper-swatch: #dce9d5; }
.notes-page { width: 100%; min-height: 235px; padding: 22px 24px; overflow-wrap: anywhere; outline: 0; resize: vertical; color: #243128; font-family: var(--mono); font-size: 12px; line-height: 1.9; box-shadow: inset 0 1px 4px rgba(0,0,0,.08); transition: background-color .2s ease; }
.notes-page:focus { box-shadow: inset 0 1px 4px rgba(0,0,0,.08), inset 3px 0 #c4f46b; }
.notes-page:empty::before { content: attr(data-placeholder); color: #778174; pointer-events: none; white-space: pre-wrap; }
.notes-page.paper-cream { background-color: #f0e9ce; background-image: repeating-linear-gradient(transparent 0 29px, rgba(102,119,91,.12) 29px 30px); }
.notes-page.paper-blue { background-color: #d9e8f4; background-image: repeating-linear-gradient(transparent 0 29px, rgba(79,119,157,.15) 29px 30px); }
.notes-page.paper-pink { background-color: #f3dfe0; background-image: repeating-linear-gradient(transparent 0 29px, rgba(164,96,103,.13) 29px 30px); }
.notes-page.paper-green { background-color: #dce9d5; background-image: repeating-linear-gradient(transparent 0 29px, rgba(88,125,83,.14) 29px 30px); }
.notes-page ul, .notes-page ol { padding-left: 24px; }
.notes-page li { padding-left: 3px; }
.editor-footer { min-height: 39px; padding: 7px 14px; display: flex; justify-content: space-between; align-items: center; gap: 12px; border-top: 1px solid #303a31; color: #778277; font-size: 9px; }
.footer-divider { padding: 0 4px; color: #566256; }
.clear-button { padding: 6px 0 6px 8px; border: 0; background: transparent; color: var(--coral); font-size: 9px; cursor: pointer; }
.clear-button:hover { color: #ffad95; }
.site-footer { min-height: 70px; padding: 0 max(6.5vw, calc((100vw - 1200px) / 2)); display: flex; align-items: center; justify-content: space-between; border-top: 1px solid #252e27; color: #7d877c; font-size: 9px; }
.footer-brand { color: var(--ink); font-size: 11px; }
.footer-brand .brand-mark { width: 25px; height: 25px; font-size: 11px; }
.back-top { color: #abb5a9; font-family: var(--mono); font-size: 9px; transition: color .2s; }
.back-top:hover { color: var(--lime); }

.flashcards-section { position: relative; padding: 77px max(6.5vw, calc((100vw - 1200px) / 2)) 88px; overflow: hidden; background: radial-gradient(ellipse at 82% 34%, rgba(87,112,255,.12), transparent 34%), linear-gradient(135deg, #111720, #171322 55%, #10171c); border-top: 1px solid rgba(98,233,226,.14); }
.flashcards-heading { max-width: 1200px; margin: 0 auto 30px; display: flex; align-items: center; justify-content: space-between; }
.flashcards-heading .eyebrow { margin-bottom: 12px; }
.flashcards-heading h2 { font-size: 30px; }
.flashcards-heading p:not(.eyebrow) { margin: 8px 0 0; color: #a1aabc; font-size: 11px; }
.flashcards-stamp { padding: 12px; border: 1px solid rgba(170,134,255,.5); border-radius: 7px; color: #c8b3ff; font-family: var(--mono); font-size: 8px; line-height: 1.8; text-align: center; transform: rotate(5deg); box-shadow: 0 7px 0 rgba(94,71,151,.2); }
.flashcards-layout { max-width: 1200px; margin: auto; display: grid; grid-template-columns: minmax(230px, .75fr) minmax(0, 1.25fr); gap: 25px; align-items: stretch; }
.flashcard-form, .flashcard-study { position: relative; padding: 20px; border: 1px solid rgba(143,157,199,.2); border-radius: 10px; background: linear-gradient(145deg, #1d2730, #181a2b 62%, #1b1926); box-shadow: 0 22px 40px rgba(0,0,0,.25), 0 6px 0 rgba(82,102,168,.14); }
.form-step, .study-topline { display: flex; align-items: center; justify-content: space-between; color: #b8c5dd; font-family: var(--mono); font-size: 9px; letter-spacing: .04em; }
.form-step b { color: var(--cyan); font-size: 16px; }
.flashcard-form label { margin: 17px 0 6px; display: block; color: #dce5f2; font-size: 10px; font-weight: 700; }
.flashcard-form textarea { width: 100%; min-height: 54px; padding: 10px; resize: vertical; border: 1px solid rgba(163,180,216,.2); border-radius: 6px; outline: 0; background: rgba(8,13,22,.55); color: #edf2ff; font-family: var(--mono); font-size: 10px; line-height: 1.65; }
.flashcard-form textarea:focus { border-color: var(--cyan); box-shadow: 0 0 0 3px rgba(98,233,226,.1); }
.flashcard-form textarea::placeholder { color: #76839b; }
.flashcard-add { width: 100%; margin-top: 15px; justify-content: space-between; border: 0; border-radius: 6px; background: linear-gradient(115deg, #74ece1, #a0ed72 58%, #d2f66d); box-shadow: 0 5px 0 #477d69, 0 12px 20px rgba(98,233,226,.13); }
.flashcard-add:hover { background: linear-gradient(115deg, #91fff2, #b5fb84 58%, #e1ff8a); }
.flashcard-save-hint { margin: 13px 0 0; color: #8692a4; font-size: 8px; }
.flashcard-study { display: flex; flex-direction: column; min-height: 330px; padding: 20px 23px 15px; border-color: rgba(98,233,226,.24); background: radial-gradient(ellipse at 50% 45%, rgba(98,233,226,.1), transparent 48%), linear-gradient(145deg, #172b31, #1d1b32 66%, #212039); }
.study-topline { color: #c1ccdc; }
.study-topline > span:first-child { display: flex; align-items: center; gap: 8px; }
.study-topline .status-dot { background: var(--cyan); box-shadow: 0 0 12px rgba(98,233,226,.6); }
.flashcard-count { color: #aab4c8; }
.flashcard-card { position: relative; width: calc(100% - 16px); min-height: 224px; flex: 1; margin: 16px 8px 13px; padding: 0; display: block; perspective: 1000px; border: 0; border-radius: 10px; background: transparent; color: #17212b; text-align: left; cursor: pointer; }
.flashcard-card:disabled { cursor: default; }
.flashcard-face { position: absolute; inset: 0; padding: 20px 23px; display: flex; flex-direction: column; justify-content: space-between; overflow: hidden; border: 1px solid rgba(255,255,255,.65); border-radius: 10px; background: linear-gradient(145deg, #f8fcff, #dce9ff 58%, #d1e2fa); box-shadow: 0 15px 0 #829dc9, 0 27px 38px rgba(0,0,0,.35), inset 0 1px 0 #fff; backface-visibility: hidden; transition: transform .55s cubic-bezier(.2,.8,.2,1); }
.flashcard-face::after { position: absolute; content: ''; width: 190px; height: 190px; right: -80px; bottom: -100px; border: 1px solid rgba(96,128,187,.25); border-radius: 50%; box-shadow: 0 0 0 14px rgba(96,128,187,.05), 0 0 0 30px rgba(96,128,187,.04); pointer-events: none; }
.flashcard-front { transform: rotateY(0); }
.flashcard-back { background: linear-gradient(145deg, #e6fff6, #c8f3e7 56%, #d5f3ed); transform: rotateY(180deg); }
.flashcard-card.flipped .flashcard-front { transform: rotateY(-180deg); }
.flashcard-card.flipped .flashcard-back { transform: rotateY(0); }
.flashcard-face-label { display: flex; justify-content: space-between; color: #61758f; font-family: var(--mono); font-size: 9px; letter-spacing: .08em; }
.flashcard-face-label b { color: #6a85b1; font-weight: 400; }
.flashcard-content { position: relative; z-index: 1; max-width: 580px; color: #18293c; font-size: clamp(17px, 2.2vw, 23px); font-weight: 800; line-height: 1.45; }
.flashcard-back .flashcard-content { color: #1a4437; }
.flip-hint { display: flex; align-items: center; justify-content: flex-end; gap: 7px; color: #637a9b; font-family: var(--mono); font-size: 9px; }
.flip-hint span { font-size: 15px; }
.flashcard-controls { display: flex; align-items: center; justify-content: center; gap: 15px; color: #d1d9e9; font-family: var(--mono); font-size: 10px; }
.flashcard-nav, .flashcard-delete { min-height: 31px; padding: 0 10px; border: 1px solid rgba(177,196,226,.25); border-radius: 5px; background: rgba(255,255,255,.04); color: #d1d9e9; font-size: 9px; cursor: pointer; transition: background .2s, transform .2s; }
.flashcard-nav:hover:not(:disabled), .flashcard-delete:hover:not(:disabled) { transform: translateY(-2px); background: rgba(98,233,226,.12); }
.flashcard-nav:disabled, .flashcard-delete:disabled { opacity: .4; cursor: not-allowed; }
.flashcard-delete { width: 29px; padding: 0; color: #ff9a87; font-size: 17px; }
.ai-tutor { max-width: 1200px; margin: 24px auto 0; padding: 19px 21px; display: grid; grid-template-columns: minmax(220px, .75fr) minmax(0, 1.25fr); gap: 12px 25px; align-items: center; border: 1px solid rgba(98,233,226,.25); border-radius: 9px; background: linear-gradient(120deg, rgba(98,233,226,.08), rgba(170,134,255,.1) 60%, rgba(255,134,103,.06)), #171b28; box-shadow: 0 17px 30px rgba(0,0,0,.2), 0 5px 0 rgba(98,233,226,.1); }
.ai-tutor-copy { display: flex; align-items: center; gap: 14px; }
.ai-orbit { width: 42px; height: 42px; flex: 0 0 auto; display: grid; place-items: center; border: 1px solid rgba(98,233,226,.5); border-radius: 50%; background: radial-gradient(circle at 35% 30%, #66efdf, #5965c9 70%); color: #fff; box-shadow: 0 0 0 5px rgba(98,233,226,.07), 0 0 24px rgba(98,233,226,.22); animation: ai-orbit 6s ease-in-out infinite; }
.ai-kicker { color: var(--cyan); font-family: var(--mono); font-size: 8px; letter-spacing: .06em; }
.ai-tutor h3 { margin: 5px 0 3px; color: var(--ink); font-size: 15px; }
.ai-tutor-copy p { margin: 0; color: #9da9bb; font-size: 9px; line-height: 1.6; }
.ai-tutor-input { display: flex; align-items: stretch; gap: 9px; }
.ai-tutor-input textarea { min-width: 0; min-height: 53px; flex: 1; padding: 10px 12px; resize: vertical; border: 1px solid rgba(163,180,216,.22); border-radius: 6px; outline: 0; background: rgba(8,13,22,.55); color: #edf2ff; font-family: var(--mono); font-size: 10px; line-height: 1.6; }
.ai-tutor-input textarea:focus { border-color: var(--cyan); box-shadow: 0 0 0 3px rgba(98,233,226,.1); }
.ai-tutor-input textarea::placeholder { color: #75839b; }
.ai-ask-button { min-width: 103px; padding: 0 12px; display: inline-flex; align-items: center; justify-content: space-between; gap: 8px; border: 0; border-radius: 6px; background: linear-gradient(120deg, #6ae5d8, #91b4ff 65%, #b395ff); color: #13202e; box-shadow: 0 4px 0 #5369a4, 0 9px 16px rgba(112,153,255,.16); font-size: 10px; font-weight: 800; cursor: pointer; transition: transform .18s, box-shadow .18s; }
.ai-ask-button:hover:not(:disabled) { transform: translateY(-2px); box-shadow: 0 6px 0 #5369a4, 0 12px 20px rgba(112,153,255,.2); }
.ai-ask-button:disabled { opacity: .65; cursor: wait; }
.ai-response { grid-column: 2; min-height: 0; margin: 0; color: #bfcbe0; font-size: 10px; line-height: 1.75; white-space: pre-wrap; overflow-wrap: anywhere; }
.ai-response.has-error { color: #ffab99; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0; }
.scroll-reveal { opacity: 0; translate: 0 24px; transition: opacity .65s ease, translate .65s cubic-bezier(.2,.75,.2,1); }
.scroll-reveal.is-visible { opacity: 1; translate: 0 0; }

body[data-theme="light"] .flashcards-section { background: radial-gradient(ellipse at 82% 34%, rgba(102,126,255,.16), transparent 34%), linear-gradient(135deg, #e5eff2, #ede8f8 55%, #e2edf0); border-color: #d4dfeb; }
body[data-theme="light"] .flashcards-heading p:not(.eyebrow) { color: #52657a; }
body[data-theme="light"] .flashcards-stamp { border-color: #a590da; color: #6d4bb0; }
body[data-theme="light"] .flashcard-form { border-color: #ced5e4; background: linear-gradient(145deg, #f6f9ff, #eeeefa 62%, #f8f2ff); box-shadow: 0 22px 40px rgba(42,53,87,.14), 0 6px 0 rgba(82,102,168,.14); }
body[data-theme="light"] .form-step, body[data-theme="light"] .study-topline { color: #45566f; }
body[data-theme="light"] .flashcard-form label { color: #36455a; }
body[data-theme="light"] .flashcard-form textarea { border-color: #cbd4e4; background: rgba(255,255,255,.85); color: #23344b; }
body[data-theme="light"] .flashcard-form textarea::placeholder { color: #7d8ba1; }
body[data-theme="light"] .flashcard-save-hint { color: #637187; }
body[data-theme="light"] .flashcard-study { border-color: #c5d5df; background: radial-gradient(ellipse at 50% 45%, rgba(98,190,200,.14), transparent 48%), linear-gradient(145deg, #e6f4f3, #ebe9f7 66%, #f1e9f2); }
body[data-theme="light"] .flashcard-controls { color: #43536b; }
body[data-theme="light"] .flashcard-nav, body[data-theme="light"] .flashcard-delete { border-color: #c2ccda; background: rgba(255,255,255,.55); color: #40506a; }
body[data-theme="light"] .flashcard-delete { color: #b34e4c; }
body[data-theme="light"] .ai-tutor { border-color: #ccd4ec; background: linear-gradient(120deg, rgba(81,205,193,.12), rgba(150,129,231,.12) 60%, rgba(245,138,117,.08)), #f7f8ff; box-shadow: 0 17px 30px rgba(58,66,103,.12), 0 5px 0 rgba(98,145,185,.1); }
body[data-theme="light"] .ai-kicker { color: #3a8790; }
body[data-theme="light"] .ai-tutor h3 { color: #25334a; }
body[data-theme="light"] .ai-tutor-copy p { color: #58677d; }
body[data-theme="light"] .ai-tutor-input textarea { border-color: #c9d2e3; background: rgba(255,255,255,.88); color: #26364c; }
body[data-theme="light"] .ai-tutor-input textarea::placeholder { color: #77869b; }
body[data-theme="light"] .ai-response { color: #43536b; }
body[data-theme="light"] .ai-response.has-error { color: #a03d37; }
body[data-theme="light"] .notes-library { border-color: #cbd8ca; }
body[data-theme="light"] .saved-note.active { background: linear-gradient(120deg, rgba(58,168,173,.14), rgba(139,103,216,.1)); }
body[data-theme="light"] .note-title-input { border-color: #d7dfd4; background: rgba(98,180,170,.08); }
body[data-theme="light"] .flashcard-face { box-shadow: 0 15px 0 #a4b7d2, 0 27px 38px rgba(53,66,100,.22), inset 0 1px 0 #fff; }
body[data-theme="light"] .flashcard-back { box-shadow: 0 15px 0 #9cc9bb, 0 27px 38px rgba(53,66,100,.2), inset 0 1px 0 #fff; }
body[data-theme="light"] .hero::before, body[data-theme="light"] .hero::after { opacity: .2; }
body[data-theme="light"] .data-cube-one { box-shadow: inset -8px -8px 14px rgba(22,44,114,.18), 9px 13px 20px rgba(38,60,95,.18), 0 0 26px rgba(40,166,200,.22); }
body[data-theme="light"] .data-cube-two { box-shadow: inset -8px -8px 14px rgba(119,28,66,.16), 9px 13px 20px rgba(73,45,77,.18), 0 0 24px rgba(220,85,181,.2); }
body[data-theme="light"] .lesson-section { background: linear-gradient(135deg, #e9eee6, #e9e9f4 55%, #e8f0ee); }

html[data-theme="light"] {
	color-scheme: light;
	--ink: #17243a;
	--muted: #5d6b7e;
	--base: #f4f7fb;
	--panel: #ffffff;
	--panel-raised: #f8fafc;
	--line: #d6deea;
	--lime: #16a34a;
	--coral: #15803d;
	--cyan: #2563eb;
	--violet: #64748b;
}
body[data-theme="light"] { background: #f3f5ef; color: #1d2b22; }
html[data-theme="light"] .topbar { border-color: #dce3d8; }
html[data-theme="light"] .brand { color: #1d2b22; }
html[data-theme="light"] .brand-mark { color: #fff; background: #527d29; }
html[data-theme="light"] .top-progress { color: #526055; }
html[data-theme="light"] .hero-description { color: #526055; }
html[data-theme="light"] .meta-icon { border-color: #c4d2bb; }
html[data-theme="light"] .meta-divider { background: #c9d2c7; }
html[data-theme="light"] .art-grid { background-image: linear-gradient(rgba(99,145,54,.11) 1px, transparent 1px), linear-gradient(90deg, rgba(99,145,54,.11) 1px, transparent 1px); }
html[data-theme="light"] .float-label { border-color: #d5dfd3; background: rgba(255,255,255,.94); color: #304337; box-shadow: 0 14px 35px rgba(35,54,34,.16); }
html[data-theme="light"] .art-index { color: #647967; }
html[data-theme="light"] .lesson-section { background: #e9eee6; border-color: #d8e0d5; }
html[data-theme="light"] .lesson-item { color: #526055; }
html[data-theme="light"] .lesson-item.selected { color: #1d2b22; }
html[data-theme="light"] .lesson-item:hover { color: #1d2b22; background: rgba(30,55,34,.05); }
html[data-theme="light"] .lesson-tip { color: #627064; }
html[data-theme="light"] .tip-mark { border-color: #bdcbb7; color: #5e8e2d; }
html[data-theme="light"] .lesson-panel { border-color: #d2dbd0; box-shadow: 0 14px 30px rgba(40,61,40,.08); }
html[data-theme="light"] .panel-tag { color: #638e36; }
html[data-theme="light"] .panel-time, html[data-theme="light"] .lesson-description { color: #627064; }
html[data-theme="light"] .panel-footer > span { color: #657365; }
html[data-theme="light"] .complete-button { border-color: #bac9b4; color: #557e2e; }
html[data-theme="light"] .complete-button:hover { color: #fff; }
html[data-theme="light"] .notebook-stamp { border-color: #91a87e; color: #547a35; }
html[data-theme="light"] .notebook-editor { border-color: #cdd8ca; background: #fff; box-shadow: 0 25px 55px rgba(43,64,43,.15), 0 8px 16px rgba(43,64,43,.11); }
html[data-theme="light"] .notebook-editor::before { border-color: #cad7c7; background: #e1e9dd; }
html[data-theme="light"] .notebook-editor::after { border-color: #d0dacd; background: #edf1e9; }
html[data-theme="light"] .editor-toolbar { border-color: #d7dfd4; color: #637064; }
html[data-theme="light"] .editor-toolbar > span:first-child { color: #425346; }
html[data-theme="light"] .editor-toolbar #save-status { color: #637064; }
html[data-theme="light"] .format-toolbar { border-color: #d7dfd4; background: linear-gradient(110deg, #f1f5ed, #e6eee2 55%, #f5f7f1); }
html[data-theme="light"] .format-button { color: #435448; }
html[data-theme="light"] .format-button:hover, html[data-theme="light"] .format-button:focus-visible { border-color: #b7c8ad; background: #e4eddd; color: #436e25; }
html[data-theme="light"] .toolbar-divider { background: #cbd6c7; }
html[data-theme="light"] .font-size-control, html[data-theme="light"] .palette-label { color: #637064; }
html[data-theme="light"] .font-size-control select { border-color: #cbd6c7; background: #fff; color: #344538; }
html[data-theme="light"] .paper-swatch { border-color: #bbc8b7; background: #e8eee4; }
html[data-theme="light"] .editor-footer { border-color: #d7dfd4; color: #667366; }
html[data-theme="light"] .footer-divider { color: #9aa899; }
html[data-theme="light"] .site-footer { border-color: #dce3d8; color: #627064; }
html[data-theme="light"] .back-top { color: #506253; }
html[data-theme="light"] .back-top:hover { color: #5f8e32; }

@keyframes rise-in { from { opacity: 0; transform: translateY(14px); } to { opacity: 1; transform: translateY(0); } }
@keyframes panel-in { from { opacity: .45; transform: translateY(4px); } to { opacity: 1; transform: translateY(0); } }
@keyframes cube-float { 0%, 100% { transform: translateY(0) rotateX(-24deg) rotateY(-36deg); } 50% { transform: translateY(-11px) rotateX(-20deg) rotateY(-30deg); } }
@keyframes data-float { 0%, 100% { translate: 0 0; } 50% { translate: 0 -9px; } }
@keyframes draw-chart { to { stroke-dashoffset: 0; } }
@keyframes ai-orbit { 0%, 100% { transform: rotate(0) translateY(0); } 50% { transform: rotate(9deg) translateY(-4px); } }
@keyframes glow-pulse { 0%, 100% { opacity: .72; } 50% { opacity: 1; } }

@media (min-width: 1350px) { .hero { padding-left: 0; padding-right: 0; } }
@media (min-width: 801px) { h1 span { white-space: nowrap; } }
@media (max-width: 1280px) { .hero, .notebook-section { margin-left: 6.5vw; margin-right: 6.5vw; } }
@media (max-width: 800px) {
	.topbar { height: 62px; padding: 0 5vw; }
	.main-nav { gap: 19px; }
	.theme-toggle, .motion-toggle { padding: 0 9px; }
	.hero { min-height: unset; margin: 0; padding: 64px 7vw 45px; grid-template-columns: 1fr .85fr; gap: 5px; }
	h1 { font-size: clamp(54px, 9vw, 74px); }
	.hero-art { height: 290px; transform: scale(.85); transform-origin: center; }
	.lesson-section { padding: 52px 7vw 66px; }
	.lesson-layout { grid-template-columns: 190px minmax(0, 1fr); gap: 15px; }
	.lesson-panel { padding: 20px; }
	.notebook-section { margin: 0 7vw; padding: 60px 0; }
	.notebook-workspace { grid-template-columns: minmax(155px, .72fr) minmax(0, 1.28fr); gap: 12px; }
	.flashcards-section { padding: 60px 7vw 68px; }
	.flashcards-layout { gap: 16px; }
	.site-footer { padding: 0 7vw; }
}
@media (max-width: 600px) {
	.topbar { padding: 0 14px; gap: 9px; }
	.brand { gap: 8px; font-size: 12px; }
	.brand-mark { width: 28px; height: 28px; }
	.main-nav { gap: 10px; }
	.nav-link { font-size: 9px; }
	.theme-toggle, .motion-toggle { width: 32px; min-height: 32px; padding: 0; justify-content: center; }
	.theme-label, .motion-label { display: none; }
	.top-progress { gap: 5px; font-size: 8px; }
	.top-progress #progress-label { display: none; }
	.top-progress .status-dot { width: 6px; height: 6px; }
	.hero { padding: 54px 22px 34px; grid-template-columns: 1fr; gap: 1px; }
	.hero-copy { padding-left: 0; }
	.eyebrow { font-size: 9px; }
	h1 { font-size: clamp(48px, 13vw, 63px); }
	.hero-description { max-width: 340px; margin: 16px 0 21px; font-size: 13px; }
	.hero-meta { margin-top: 20px; }
	.hero-art { height: 255px; margin-top: 8px; transform: scale(.82); }
	.data-cube-one { right: 8%; top: 58px; }
	.data-cube-two { left: 7%; bottom: 60px; }
	.data-card { right: 4%; top: 111px; transform: scale(.86) perspective(500px) rotateY(-15deg) rotateX(7deg); }
	.label-top { left: 0; top: 25px; }
	.label-bottom { right: 0; bottom: 27px; }
	.lesson-section { padding: 45px 20px 55px; }
	.section-heading { align-items: start; gap: 12px; flex-direction: column; margin-bottom: 20px; }
	h2 { font-size: 23px; }
	.section-note { margin: 0; }
	.lesson-layout { grid-template-columns: 1fr; gap: 17px; }
	.lesson-list { display: grid; grid-template-columns: 1fr 1fr; border-top: 0; gap: 6px; }
	.lesson-item { min-height: 47px; grid-template-columns: 25px 1fr 12px; padding: 0 9px; border: 1px solid var(--line); }
	.lesson-item:hover { padding-left: 12px; }
	.lesson-name { font-size: 10px; }
	.lesson-number { font-size: 9px; }
	.lesson-tip { grid-column: 1 / -1; margin: 3px 0 0; padding: 7px 2px 0; }
	.lesson-panel { min-height: unset; padding: 19px 15px 15px; }
	.lesson-panel h3 { margin-top: 15px; font-size: 18px; }
	.lesson-description { font-size: 10px; }
	.code-window pre { font-size: 10px; }
	.panel-footer { align-items: flex-start; flex-direction: column; }
	.complete-button { align-self: flex-end; }
	.notebook-section { margin: 0 20px; padding: 50px 0; }
	.notebook-workspace { grid-template-columns: 1fr; gap: 13px; }
	.notes-library { padding: 11px; }
	.notes-list { max-height: 165px; }
	.flashcards-section { padding: 53px 20px 60px; }
	.flashcards-heading { align-items: flex-start; gap: 12px; }
	.flashcards-heading h2 { font-size: 24px; }
	.flashcards-heading > div { min-width: 0; }
	.flashcards-stamp { flex: 0 0 auto; margin-top: 10px; padding: 8px; font-size: 7px; }
	.flashcards-layout { grid-template-columns: 1fr; gap: 15px; }
	.ai-tutor { grid-template-columns: 1fr; gap: 13px; padding: 15px; }
	.ai-response { grid-column: 1; }
	.flashcard-form, .flashcard-study { padding: 15px; }
	.flashcard-study { min-height: 310px; }
	.flashcard-card { min-height: 212px; margin: 14px 5px 12px; }
	.flashcard-face { padding: 17px; }
	.flashcard-controls { gap: 8px; }
	.flashcard-nav { padding: 0 8px; }
	.notebook-heading { align-items: flex-start; gap: 10px; }
	.notebook-heading h2 { max-width: 230px; font-size: 22px; }
	.notebook-subtitle { max-width: 260px; line-height: 1.7; }
	.notebook-stamp { flex: 0 0 auto; margin-top: 18px; font-size: 7px; }
	.editor-toolbar { padding: 0 10px; font-size: 8px; }
	.notebook-editor::before { inset: 5px -5px -5px 5px; }
	.notebook-editor::after { inset: 9px -9px -9px 9px; }
	.format-toolbar { gap: 9px; padding: 9px; }
	.format-group { gap: 3px; }
	.font-size-control { font-size: 8px; }
	.font-size-control select { max-width: 83px; }
	.color-options, .paper-options { gap: 6px; }
	.notes-page { min-height: 205px; padding: 17px 13px; font-size: 11px; }
	.editor-footer { align-items: flex-start; font-size: 8px; }
	.site-footer { min-height: 64px; padding: 0 18px; gap: 12px; }
	.site-footer > span { display: none; }
	.back-top { font-size: 8px; }
}

@media (prefers-reduced-motion: reduce) {
	html:not([data-motion="on"]), html:not([data-motion="on"]) *, html:not([data-motion="on"]) *::before, html:not([data-motion="on"]) *::after { scroll-behavior: auto !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
	html:not([data-motion="on"]) .scroll-reveal { opacity: 1; translate: none; }
}

.scroll-progress span { background: linear-gradient(90deg, #2563eb, #60a5fa 52%, #4ade80); }
.brand-dot, .theme-icon, .motion-icon, .eyebrow, .eyebrow-line, .nav-link.active::after { color: var(--lime); }
.hero::before { background: var(--cyan); }
.hero::after { background: var(--violet); }
h1 span { background-image: linear-gradient(100deg, #60a5fa, #4ade80); filter: drop-shadow(0 0 23px rgba(96,165,250,.15)); }
.primary-button { background: linear-gradient(110deg, #4ade80, #bbf7d0); box-shadow: 0 5px 0 #15803d, 0 12px 24px rgba(74,222,128,.12); }
.primary-button:hover { background: linear-gradient(110deg, #86efac, #dcfce7); box-shadow: 0 8px 0 #15803d, 0 17px 30px rgba(74,222,128,.18); }
.art-grid { background-image: linear-gradient(rgba(96,165,250,.08) 1px, transparent 1px), linear-gradient(90deg, rgba(96,165,250,.08) 1px, transparent 1px); }
.orbit { border-color: rgba(96,165,250,.26); }
.orbit-two { border-color: rgba(74,222,128,.2); }
.data-cube-two { background: linear-gradient(145deg, #86efac, #16a34a 65%, #166534); color: #052e16; box-shadow: inset -8px -8px 14px rgba(4,70,30,.2), 9px 13px 20px rgba(0,0,0,.24), 0 0 24px rgba(74,222,128,.18); }
.data-card { border-color: rgba(96,165,250,.28); background: linear-gradient(145deg, rgba(30,48,74,.98), rgba(17,26,40,.98)); }
.data-sparkline path { stroke: #4ade80; }
.data-sparkline circle { fill: #60a5fa; }
.cube-front { background: linear-gradient(145deg, #93c5fd, #2563eb 72%); color: #eff6ff; box-shadow: inset -12px -12px 30px rgba(10,32,86,.2); }
.cube-spark { color: #bbf7d0; }
.cube-back { background: #173b70; }
.cube-right { background: linear-gradient(140deg, #4ade80, #15803d); }
.cube-left { background: #166534; }
.cube-top { background: #bfdbfe; }
.cube-bottom { background: #102748; }
.lesson-section { background: linear-gradient(135deg, #0d1522, #111a28 55%, #0c1420); border-color: #29364a; }
.code-keyword { color: #93c5fd; }
.code-function { color: #4ade80; }
.color-swatch[data-ink="#2563eb"] { --swatch: #2563eb; }
.color-swatch[data-ink="#16a34a"] { --swatch: #16a34a; }
.color-swatch[data-ink="#64748b"] { --swatch: #64748b; }
.color-swatch[data-ink="#152238"] { --swatch: #152238; }
.notes-page.paper-cream { background-color: #fff; background-image: repeating-linear-gradient(transparent 0 29px, rgba(100,116,139,.14) 29px 30px); }
.notes-page.paper-blue { background-color: #e8f1ff; background-image: repeating-linear-gradient(transparent 0 29px, rgba(37,99,235,.14) 29px 30px); }
.notes-page.paper-pink { background-color: #e9edf3; background-image: repeating-linear-gradient(transparent 0 29px, rgba(100,116,139,.14) 29px 30px); }
.notes-page.paper-green { background-color: #e8f5ec; background-image: repeating-linear-gradient(transparent 0 29px, rgba(22,163,74,.14) 29px 30px); }
.paper-swatch[data-paper="cream"] { --paper-swatch: #fff; }
.paper-swatch[data-paper="blue"] { --paper-swatch: #bfdbfe; }
.paper-swatch[data-paper="pink"] { --paper-swatch: #cbd5e1; }
.paper-swatch[data-paper="green"] { --paper-swatch: #bbf7d0; }
.ai-tutor { border-color: rgba(96,165,250,.3); background: linear-gradient(120deg, rgba(96,165,250,.1), rgba(74,222,128,.08) 60%), #111a28; box-shadow: 0 17px 30px rgba(0,0,0,.2), 0 5px 0 rgba(96,165,250,.1); }
.ai-orbit { border-color: rgba(96,165,250,.6); background: radial-gradient(circle at 35% 30%, #4ade80, #2563eb 76%); box-shadow: 0 0 0 5px rgba(96,165,250,.08), 0 0 24px rgba(96,165,250,.2); }
.ai-tutor-input { display: grid; grid-template-columns: minmax(0, .8fr) minmax(0, 1.3fr) auto; align-items: stretch; }
.ai-tutor-input input, .ai-tutor-input textarea { width: 100%; min-width: 0; min-height: 53px; padding: 10px 12px; border: 1px solid rgba(148,163,184,.3); border-radius: 6px; outline: 0; background: rgba(8,13,22,.55); color: #edf2ff; font-family: var(--mono); font-size: 10px; line-height: 1.6; }
.ai-tutor-input input:focus, .ai-tutor-input textarea:focus { border-color: var(--cyan); box-shadow: 0 0 0 3px rgba(96,165,250,.1); }
.ai-tutor-input input::placeholder, .ai-tutor-input textarea::placeholder { color: #8795a9; }
.ai-captcha { grid-column: 2; }
.ai-captcha[hidden] { display: none; }
.ai-ask-button { background: linear-gradient(120deg, #4ade80, #bbf7d0); color: #10251a; box-shadow: 0 4px 0 #15803d, 0 9px 16px rgba(74,222,128,.15); }
.ai-ask-button:hover:not(:disabled) { box-shadow: 0 6px 0 #15803d, 0 12px 20px rgba(74,222,128,.2); }

html[data-theme="light"] .hero::before, html[data-theme="light"] .hero::after { opacity: .14; }
html[data-theme="light"] .art-grid { background-image: linear-gradient(rgba(37,99,235,.1) 1px, transparent 1px), linear-gradient(90deg, rgba(37,99,235,.1) 1px, transparent 1px); }
html[data-theme="light"] .float-label { border-color: #d6deea; color: #334155; }
html[data-theme="light"] .lesson-section { background: linear-gradient(135deg, #eaf1fb, #f3f6fa 56%, #eaf4ee); border-color: #d6deea; }
html[data-theme="light"] .ai-tutor { border-color: #d1dceb; background: linear-gradient(120deg, rgba(37,99,235,.08), rgba(22,163,74,.07) 60%), #fff; }
html[data-theme="light"] .ai-tutor-input input { border-color: #cbd5e1; background: #fff; color: #17243a; }
html[data-theme="light"] .ai-tutor-input input::placeholder { color: #64748b; }

@media (max-width: 700px) {
	.ai-tutor-input { grid-template-columns: 1fr; }
	.ai-ask-button { min-height: 42px; }
	.ai-captcha { grid-column: 1; }
}