:root{--ink-950: #03050e;--ink-900: #060a17;--ink-850: #080d1f;--ink-800: #0b1226;--ink-700: #121b36;--ink-600: #1c284a;--ink-500: #33406b;--ink-400: #64719c;--ink-300: #97a2c4;--ink-200: #c3cbe3;--ink-100: #e8edf9;--ink-50: #f4f7ff;--brand-300: #8ebdff;--brand-400: #5997ff;--brand-500: #2f72ff;--brand-600: #1657f0;--brand-700: #0f43cc;--aqua-300: #7ee7ff;--aqua-400: #38d0f5;--aqua-500: #12b6e6;color-scheme:light;--bg-main: #f4f7ff;--bg-mesh: radial-gradient(1100px 620px at 78% -8%, rgba(47, 114, 255, .1), transparent 60%), radial-gradient(900px 560px at 8% 12%, rgba(18, 182, 230, .1), transparent 55%), linear-gradient(180deg, #f6f9ff 0%, #eef3ff 55%, #eaf0ff 100%);--surface: rgba(255, 255, 255, .72);--surface-solid: #ffffff;--surface-soft: rgba(11, 18, 38, .03);--surface-hover: rgba(255, 255, 255, .92);--border: rgba(11, 18, 38, .09);--border-strong: rgba(11, 18, 38, .16);--border-brand: rgba(47, 114, 255, .42);--text-main: #0b1226;--text-sub: #33406b;--text-muted: #64719c;--primary: #1657f0;--primary-hover: #0f43cc;--primary-soft: rgba(47, 114, 255, .1);--primary-gradient: linear-gradient(135deg, #1657f0 0%, #2f72ff 48%, #38d0f5 100%);--primary-glow: rgba(47, 114, 255, .28);--accent: #12b6e6;--text-gradient: linear-gradient(100deg, #1657f0 0%, #2f72ff 45%, #12b6e6 100%);--easy: #059669;--easy-bg: rgba(16, 185, 129, .12);--easy-border: rgba(5, 150, 105, .3);--medium: #b45309;--medium-bg: rgba(245, 158, 11, .14);--medium-border: rgba(180, 83, 9, .28);--hard: #dc2626;--hard-bg: rgba(239, 68, 68, .12);--hard-border: rgba(220, 38, 38, .26);--header-bg: rgba(244, 247, 255, .72);--code-bg: #060a17;--code-text: #e8edf9;--overlay-bg: rgba(6, 10, 23, .55);--grid-line: rgba(11, 18, 38, .045);--shadow-sm: 0 10px 30px -22px rgba(11, 18, 38, .45);--shadow-card: 0 26px 60px -36px rgba(11, 18, 38, .42);--shadow-pop: 0 40px 100px -48px rgba(11, 18, 38, .55);--shadow-brand: 0 26px 70px -30px rgba(47, 114, 255, .75);--radius-sm: 10px;--radius-md: 14px;--radius-lg: 20px;--radius-xl: 26px;--radius-2xl: 32px;--font-sans: "Inter", ui-sans-serif, system-ui, -apple-system, sans-serif;--font-display: "Sora", "Inter", ui-sans-serif, system-ui, sans-serif;--font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, monospace;--safe-top: env(safe-area-inset-top, 0px);--safe-bottom: env(safe-area-inset-bottom, 0px);--safe-left: env(safe-area-inset-left, 0px);--safe-right: env(safe-area-inset-right, 0px);--learn-sticky-top: calc(56px + var(--safe-top))}[data-theme=dark]{color-scheme:dark;--bg-main: #03050e;--bg-mesh: radial-gradient(1100px 620px at 80% -10%, rgba(47, 114, 255, .22), transparent 60%), radial-gradient(900px 560px at 5% 10%, rgba(18, 182, 230, .16), transparent 55%), linear-gradient(180deg, #03050e 0%, #060a17 55%, #04070f 100%);--surface: rgba(11, 18, 38, .55);--surface-solid: #0b1226;--surface-soft: rgba(255, 255, 255, .03);--surface-hover: rgba(28, 40, 74, .55);--border: rgba(255, 255, 255, .08);--border-strong: rgba(255, 255, 255, .16);--border-brand: rgba(89, 151, 255, .45);--text-main: #e8edf9;--text-sub: #c3cbe3;--text-muted: #97a2c4;--primary: #5997ff;--primary-hover: #8ebdff;--primary-soft: rgba(47, 114, 255, .16);--primary-gradient: linear-gradient(135deg, #1657f0 0%, #2f72ff 48%, #38d0f5 100%);--primary-glow: rgba(47, 114, 255, .45);--accent: #38d0f5;--text-gradient: linear-gradient(100deg, #8ebdff 0%, #2f72ff 45%, #38d0f5 100%);--easy: #34d399;--easy-bg: rgba(16, 185, 129, .14);--easy-border: rgba(52, 211, 153, .32);--medium: #fbbf24;--medium-bg: rgba(245, 158, 11, .14);--medium-border: rgba(251, 191, 36, .32);--hard: #f87171;--hard-bg: rgba(239, 68, 68, .14);--hard-border: rgba(248, 113, 113, .32);--header-bg: rgba(3, 5, 14, .72);--code-bg: #03050e;--code-text: #e8edf9;--overlay-bg: rgba(3, 5, 14, .78);--grid-line: rgba(255, 255, 255, .05);--shadow-sm: 0 10px 30px -20px rgba(0, 0, 0, .9);--shadow-card: 0 30px 80px -40px rgba(0, 0, 0, 1);--shadow-pop: 0 40px 110px -46px rgba(0, 0, 0, 1);--shadow-brand: 0 30px 80px -30px rgba(47, 114, 255, .85)}*{margin:0;padding:0;box-sizing:border-box}html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:calc(4.5rem + var(--safe-top))}html.cap-native{--safe-top: max(env(safe-area-inset-top, 0px), 28px);--learn-sticky-top: calc(56px + var(--safe-top))}html.cap-native .detail-top-bar{padding-top:var(--safe-top)}body{font-family:var(--font-sans);background-color:var(--bg-main);background-image:var(--bg-mesh);background-attachment:fixed;color:var(--text-main);line-height:1.65;min-height:100vh;overflow-x:hidden;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility;transition:background-color .4s ease,color .4s ease}h1,h2,h3,h4,h5{font-family:var(--font-display);letter-spacing:-.02em;line-height:1.15}a{color:inherit}img,video{display:block;max-width:100%}button{font-family:inherit}::selection{background:color-mix(in oklab,var(--brand-500) 40%,transparent);color:#fff}::-webkit-scrollbar{width:10px;height:10px}::-webkit-scrollbar-track{background:transparent}::-webkit-scrollbar-thumb{background:linear-gradient(var(--brand-600),var(--aqua-500));border-radius:999px;border:2px solid var(--bg-main)}.aurora-backdrop{position:fixed;top:0;right:0;bottom:0;left:0;z-index:0;overflow:hidden;pointer-events:none}.aurora-grid{position:absolute;top:0;right:0;bottom:0;left:0;background-image:linear-gradient(to right,var(--grid-line) 1px,transparent 1px),linear-gradient(to bottom,var(--grid-line) 1px,transparent 1px);background-size:62px 62px;-webkit-mask-image:linear-gradient(to bottom,#000 42%,transparent 85%);mask-image:linear-gradient(to bottom,#000 42%,transparent 85%)}.aurora-blob{position:absolute;border-radius:50%;filter:blur(130px);opacity:.55}.blob-1{width:40rem;height:40rem;top:-14rem;left:-12rem;background:#2f72ff47;animation:drift 26s ease-in-out infinite alternate}.blob-2{width:34rem;height:34rem;top:4rem;right:-12rem;background:#12b6e638;animation:drift 30s ease-in-out infinite alternate;animation-delay:-9s}.blob-3{width:30rem;height:30rem;bottom:-8rem;left:30%;background:#5997ff29;animation:drift 34s ease-in-out infinite alternate;animation-delay:-16s}.aurora-vignette{position:absolute;top:0;right:0;bottom:0;left:0;background:radial-gradient(ellipse at 50% -10%,transparent 30%,var(--bg-main) 92%);opacity:.85}.container{max-width:1240px;margin:0 auto;padding:0 24px;position:relative;z-index:1}.text-gradient{background-image:var(--text-gradient);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;color:transparent}.glass{background:var(--surface);backdrop-filter:blur(16px) saturate(130%);-webkit-backdrop-filter:blur(16px) saturate(130%);border:1px solid var(--border)}.glass-strong{background:var(--surface);backdrop-filter:blur(22px) saturate(150%);-webkit-backdrop-filter:blur(22px) saturate(150%);border:1px solid var(--border);box-shadow:var(--shadow-card)}[data-theme=dark] .glass-strong{background:color-mix(in oklab,var(--ink-800) 72%,transparent)}.ring-glow{box-shadow:0 0 0 1px var(--border-brand),var(--shadow-brand)}.section{padding:72px 0}.reveal{opacity:0;transform:translateY(28px);transition:opacity .7s cubic-bezier(.22,1,.36,1),transform .7s cubic-bezier(.22,1,.36,1);will-change:opacity,transform}.reveal.is-visible{opacity:1;transform:none}.spotlight{position:relative;overflow:hidden}.spotlight:before{content:"";position:absolute;top:0;right:0;bottom:0;left:0;pointer-events:none;opacity:0;transition:opacity .35s ease;background:radial-gradient(340px circle at var(--mx, 50%) var(--my, 0%),var(--primary-soft),transparent 68%)}.spotlight:hover:before{opacity:1}.icon{display:inline-flex;align-items:center;justify-content:center;flex:none}.icon-svg{width:1.15em;height:1.15em;display:block}.promo-banner{position:relative;z-index:101;padding:9px 0;font-size:.86rem;color:#eaf0ff;background:linear-gradient(100deg,#0b1226eb,#0f43cc8c 45%,#12b6e659),#0b1226;border-bottom:1px solid rgba(255,255,255,.1);overflow:hidden}.promo-banner:after{content:"";position:absolute;top:0;right:0;bottom:0;left:0;background:linear-gradient(100deg,transparent 30%,rgba(255,255,255,.1) 50%,transparent 70%);background-size:220% 100%;animation:shimmer 4.5s linear infinite;pointer-events:none}.promo-content{display:flex;align-items:center;justify-content:center;gap:14px;flex-wrap:wrap;text-align:center}.promo-badge{font-size:.68rem;font-weight:800;letter-spacing:.02em;padding:3px 11px;border-radius:999px;color:#fff;background:linear-gradient(135deg,var(--brand-600),var(--brand-400));box-shadow:0 8px 22px -10px #2f72ffe6;white-space:nowrap}.free-badge-promo{font-size:.68rem;font-weight:800;letter-spacing:.02em;padding:3px 11px;border-radius:999px;color:#fff;background:linear-gradient(135deg,#059669,#10b981);box-shadow:0 8px 22px -12px #10b981e6;white-space:nowrap}.promo-text{color:#eaf0ffd1;font-weight:500}.promo-cta{color:var(--aqua-300);font-weight:700;text-decoration:none;font-size:.84rem;white-space:nowrap;transition:color .2s ease,transform .2s ease}.promo-cta:hover{color:#fff;transform:translate(2px)}header{position:sticky;top:0;z-index:100;padding:calc(12px + var(--safe-top)) 0 12px;background:var(--header-bg);backdrop-filter:blur(20px) saturate(140%);-webkit-backdrop-filter:blur(20px) saturate(140%);border-bottom:1px solid var(--border);transition:background .3s ease,border-color .3s ease,padding .3s ease}header.scrolled{padding:calc(8px + var(--safe-top)) 0 8px;box-shadow:var(--shadow-sm)}.scroll-progress{position:absolute;left:0;top:0;height:2px;width:0%;background:linear-gradient(90deg,var(--brand-500),var(--brand-300),var(--aqua-400));box-shadow:0 0 16px #2f72ffb3;transition:width .1s linear}.header-content{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:18px}.brand{display:flex;align-items:center;gap:14px;text-decoration:none}.logo-icon,.brand-logo-img{width:50px;height:50px;object-fit:cover;border-radius:14px;border:1px solid rgba(255,255,255,.25);box-shadow:0 14px 34px -16px #2f72ffe6;transition:transform .25s ease,box-shadow .25s ease}.brand-logo-img:hover{transform:scale(1.06) rotate(-2deg);box-shadow:0 18px 42px -16px #2f72ff}.brand-text h1{font-size:22px;font-weight:800;color:var(--text-main)}.brand-text p{font-size:12.5px;color:var(--text-muted);font-weight:500}.brand-title-row{display:flex;align-items:center;gap:10px}.visual-tag{font-size:.66rem;font-weight:700;letter-spacing:.03em;padding:3px 10px;border-radius:999px;color:var(--primary);background:var(--primary-soft);border:1px solid var(--border-brand);white-space:nowrap}.header-toolbar{display:flex;align-items:center;gap:8px;margin-left:auto}.header-actions{display:flex;align-items:center;gap:10px}.page-nav{display:flex;align-items:center;gap:4px}.page-nav a{display:inline-flex;align-items:center;gap:6px;padding:8px 16px;font-size:13.5px;font-weight:600;color:var(--text-muted);text-decoration:none;border:1px solid transparent;border-radius:999px;transition:color .2s ease,background .2s ease,border-color .2s ease}.page-nav a .icon-svg{width:18px;height:18px}.page-nav a:hover{color:var(--text-main);background:var(--surface-soft)}.page-nav a.active{color:var(--primary);background:var(--primary-soft);border-color:var(--border-brand)}.theme-toggle-btn{display:inline-flex;align-items:center;gap:8px;padding:10px 18px;font-size:13px;font-weight:700;color:var(--text-main);background:var(--surface);border:1px solid var(--border);border-radius:999px;cursor:pointer;-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);transition:transform .25s ease,border-color .25s ease,box-shadow .25s ease}.theme-toggle-btn:hover{transform:translateY(-1px);border-color:var(--border-brand);box-shadow:var(--shadow-brand)}.playlist-btn{display:inline-flex;align-items:center;gap:9px;padding:10px 20px;font-size:13.5px;font-weight:700;color:#fff;text-decoration:none;border-radius:999px;background:linear-gradient(135deg,#ef4444,#dc2626);box-shadow:0 16px 40px -18px #ef4444f2;transition:transform .25s ease,box-shadow .25s ease}.playlist-btn:hover{transform:translateY(-2px);box-shadow:0 22px 50px -18px #ef4444}.yt-play-icon{font-size:11px}.hero-section{padding:56px 0 24px;text-align:center}.hero-content{max-width:1040px;margin:0 auto;display:flex;flex-direction:column;align-items:center}.hero-tag{display:inline-flex;align-items:center;gap:9px;padding:7px 18px;font-size:.72rem;font-weight:700;letter-spacing:.04em;color:var(--brand-400);background:var(--surface);border:1px solid var(--border-brand);border-radius:999px;-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);margin-bottom:22px}.hero-tag:before{content:"";width:7px;height:7px;border-radius:50%;background:var(--aqua-400);box-shadow:0 0 12px 2px var(--aqua-400);animation:pulse 2.4s ease-in-out infinite}.hero-title{font-size:clamp(2.3rem,5vw,4.1rem);font-weight:800;color:var(--text-main);margin-bottom:20px}.hero-gradient-text{background-image:var(--text-gradient);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}.hero-subtitle{font-size:1.1rem;max-width:720px;color:var(--text-muted);line-height:1.7;font-weight:450;margin-bottom:28px}.hero-subtitle strong{color:var(--text-sub);font-weight:700}.hero-cta-group{display:flex;align-items:center;justify-content:center;gap:14px;flex-wrap:wrap;margin-bottom:30px}.hero-main-cta{display:inline-flex;align-items:center;gap:9px;padding:14px 30px;font-size:.96rem;font-weight:700;color:#fff;text-decoration:none;border-radius:18px;background:var(--primary-gradient);box-shadow:var(--shadow-brand);transition:transform .25s ease,box-shadow .25s ease}.hero-main-cta:hover{transform:translateY(-2px) scale(1.01);box-shadow:0 32px 80px -26px #2f72ff}.hero-secondary-cta{display:inline-flex;align-items:center;gap:9px;padding:14px 24px;font-size:.92rem;font-weight:600;color:var(--text-main);text-decoration:none;border-radius:18px;background:var(--surface);border:1px solid var(--border-strong);-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);transition:transform .25s ease,border-color .25s ease,background .25s ease}.hero-secondary-cta:hover{transform:translateY(-2px);border-color:var(--border-brand);background:var(--surface-hover)}.hero-companies{width:100%;max-width:860px;margin:0 auto 40px;padding:14px 0;border-top:1px solid var(--border);border-bottom:1px solid var(--border)}.companies-label{display:block;font-size:.7rem;font-weight:700;letter-spacing:.08em;color:var(--text-muted);margin-bottom:14px}.marquee{display:flex;overflow:hidden;-webkit-mask-image:linear-gradient(to right,transparent,#000 10%,#000 90%,transparent);mask-image:linear-gradient(to right,transparent,#000 10%,#000 90%,transparent)}.marquee-track{display:flex;flex-shrink:0;align-items:center;gap:12px;padding-right:12px;animation:marquee 34s linear infinite}.marquee:hover .marquee-track{animation-play-state:paused}.company-badge{display:inline-flex;align-items:center;gap:7px;padding:7px 16px;font-size:.84rem;font-weight:600;white-space:nowrap;color:var(--text-sub);background:var(--surface-soft);border:1px solid var(--border);border-radius:999px}.hero-visual-showcase{width:100%;max-width:940px;margin:0 auto 46px;padding:22px;text-align:left;border-radius:var(--radius-2xl)}.showcase-header{display:flex;align-items:center;justify-content:space-between;gap:12px;flex-wrap:wrap;margin-bottom:16px}.showcase-badge{display:inline-block;font-size:.66rem;font-weight:800;letter-spacing:.02em;padding:4px 11px;border-radius:999px;color:#fff;background:linear-gradient(135deg,var(--brand-600),var(--brand-400));box-shadow:0 10px 26px -12px #2f72fff2;margin-bottom:6px}.showcase-title-group h3{font-size:1.15rem;font-weight:700;color:var(--text-main)}.showcase-tag{padding:5px 14px;font-size:.78rem;font-weight:700;color:var(--primary);background:var(--primary-soft);border:1px solid var(--border-brand);border-radius:999px}.showcase-video-wrapper{position:relative;width:100%;padding-bottom:56.25%;border-radius:var(--radius-lg);overflow:hidden;background:#000;box-shadow:var(--shadow-pop)}.showcase-video-wrapper video{position:absolute;top:0;right:0;bottom:0;left:0;width:100%;height:100%;object-fit:cover;border:0}.showcase-footer{margin-top:16px;padding:12px 16px;font-size:.88rem;color:var(--text-muted);background:var(--surface-soft);border:1px solid var(--border);border-radius:var(--radius-md)}.showcase-footer strong{color:var(--text-sub)}.learn-hero{padding:52px 0 6px;text-align:center}.learn-hero .hero-tag{margin-bottom:18px}.learn-hero .hero-subtitle{margin-left:auto;margin-right:auto;margin-bottom:0}.learn-title{font-size:clamp(2rem,4vw,3.2rem);font-weight:800;color:var(--text-main);margin-bottom:18px}.cta-band{margin:40px auto 4px;padding:48px 32px;text-align:center;border-radius:var(--radius-2xl);display:flex;flex-direction:column;align-items:center}.cta-band .hero-tag{margin-bottom:18px}.cta-band h2{font-size:clamp(1.7rem,3.4vw,2.6rem);font-weight:800;color:var(--text-main);margin-bottom:14px}.cta-band p{max-width:620px;color:var(--text-muted);font-size:1.02rem;line-height:1.7;margin-bottom:26px}.feature-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:18px;width:100%}.feature-card{padding:26px 24px;text-align:left;border-radius:var(--radius-xl);background:var(--surface-soft);border:1px solid var(--border);-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);transition:transform .3s ease,border-color .3s ease,box-shadow .3s ease,background .3s ease}.feature-card:hover{transform:translateY(-5px);border-color:var(--border-brand);background:var(--surface);box-shadow:var(--shadow-card)}.feature-icon{display:grid;place-items:center;width:50px;height:50px;color:var(--primary);margin-bottom:16px;border-radius:16px;border:1px solid var(--border);background:linear-gradient(135deg,var(--primary-soft),rgba(18,182,230,.12))}.feature-icon .icon-svg{width:26px;height:26px}.feature-card h3{font-size:1.03rem;font-weight:700;color:var(--text-main);margin-bottom:8px}.feature-card p{font-size:.86rem;color:var(--text-muted);line-height:1.6}.progress-bar-container{margin-top:22px;padding:16px 20px;display:flex;flex-direction:column;align-items:stretch;gap:12px;border-radius:var(--radius-lg)}.progress-header{display:flex;align-items:center;justify-content:space-between;gap:12px}.progress-label{margin:0;font-size:.875rem;font-weight:600;color:var(--text-sub);letter-spacing:.01em}.progress-pct{margin:0;font-family:var(--font-display);font-size:clamp(1.35rem,4vw,1.65rem);font-weight:800;line-height:1;color:var(--primary);font-variant-numeric:tabular-nums;flex-shrink:0}.progress-meta{display:flex;align-items:center;justify-content:space-between;gap:10px;flex-wrap:nowrap;min-width:0}.readiness-pill{display:inline-flex;align-items:center;gap:5px;flex-shrink:0;max-width:58%;font-size:.72rem;font-weight:700;letter-spacing:.02em;padding:4px 10px;border-radius:999px;color:var(--medium);background:var(--medium-bg);border:1px solid var(--medium-border);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.readiness-pill .icon-svg{width:12px;height:12px;flex-shrink:0}.readiness-pill.ready-master{color:var(--easy);background:var(--easy-bg);border-color:var(--easy-border)}.progress-stat{min-width:0;font-family:var(--font-sans);font-size:.8125rem;font-weight:600;color:var(--text-muted);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.progress-track{width:100%;min-width:0;height:8px;border-radius:999px;background:color-mix(in oklab,var(--text-muted) 24%,transparent);border:1px solid color-mix(in oklab,var(--border-strong) 65%,transparent);overflow:hidden}.progress-fill{height:100%;width:0%;border-radius:999px;background:linear-gradient(90deg,var(--brand-600),var(--brand-400),var(--aqua-400));box-shadow:0 0 18px #2f72ff99;transition:width .6s cubic-bezier(.22,1,.36,1)}.controls-section{padding:32px 0 24px}.search-bar{margin-bottom:18px}.search-field{position:relative;width:100%}.search-input{width:100%;padding:17px 22px 17px 54px;font-size:15.5px;color:var(--text-main);background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-lg);outline:none;-webkit-backdrop-filter:blur(14px);backdrop-filter:blur(14px);transition:border-color .25s ease,box-shadow .25s ease,background .25s ease}.search-input::placeholder{color:var(--text-muted)}.search-input:focus{border-color:var(--border-brand);box-shadow:0 0 0 4px var(--primary-soft),var(--shadow-brand);background:var(--surface-hover)}.search-icon{position:absolute;left:16px;top:50%;z-index:1;display:inline-flex;align-items:center;justify-content:center;font-size:17px;line-height:0;opacity:.75;pointer-events:none;transform:translateY(-50%)}.search-icon .icon-svg{width:18px;height:18px}.filters-row{display:flex;gap:14px;flex-wrap:wrap;align-items:center;margin-bottom:18px}body.page-learn{--learn-gutter-left: 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