:root{--bg: #020b18;--bg-soft: #061427;--surface: #ffffff;--surface-soft: #f5f7fb;--text: #0f172a;--muted: #5b6472;--white: #ffffff;--primary: #1e7bff;--primary-dark: #0f5fe0;--primary-soft: #eaf3ff;--gold: #1e7bff;--green: #1e7bff;--blue: #1e7bff;--border: rgba(15, 23, 42, .08);--dark-border: rgba(255, 255, 255, .08);--container: 1180px;--radius: 22px;--shadow: 0 24px 60px rgba(0, 0, 0, .18)}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;font-family:Inter,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;background:var(--surface-soft);color:var(--text)}a{color:inherit;text-decoration:none}p{line-height:1.7}.container{width:min(var(--container),calc(100% - 32px));margin:0 auto}.site-header{position:sticky;top:0;z-index:50;background:#020b18;backdrop-filter:blur(14px);border-bottom:1px solid rgba(255,255,255,.08)}.header-inner{min-height:74px;display:flex;align-items:center;justify-content:space-between;gap:24px}.logo{display:flex;align-items:center;gap:10px;color:var(--white);font-weight:850;letter-spacing:-.03em}.logo-icon{width:38px;height:38px;display:grid;place-items:center;border-radius:12px;background:linear-gradient(135deg,#fff,#dce8ff);color:#156df0;font-size:1.35rem}.nav{display:flex;gap:24px;color:#ffffffd1;font-size:.95rem;font-weight:650}.nav a{position:relative;padding:27px 0;transition:color .2s ease}.nav a:hover{color:var(--primary)}.nav a:after{content:"";position:absolute;left:0;bottom:18px;width:0;height:3px;border-radius:999px;background:var(--primary);transition:width .2s ease}.nav a:hover:after{width:100%}.hero,.opening-hero,.page-hero{background-color:#020b18;color:var(--white)}.hero{padding:92px 0;min-height:620px;display:flex;align-items:center;background-image:linear-gradient(90deg,#020b18f5,#020b18d6 36%,#020b1861 62%,#020b181f),url(/hero-aperturas-ajedrez-tablero-oscuro.webp);background-size:cover;background-position:center right;background-repeat:no-repeat}.hero-grid,.opening-hero-grid{display:grid;grid-template-columns:1.1fr .9fr;align-items:center;gap:48px}.hero-content{max-width:760px}.hero-content h1,.opening-hero h1,.page-hero h1{font-size:clamp(2.7rem,6vw,5.2rem);line-height:.98;letter-spacing:-.07em;margin:14px 0 22px;color:var(--white)}.hero-content h1:after{content:"";display:block;width:72px;height:4px;border-radius:999px;background:var(--primary);margin-top:24px}.hero-accent{color:var(--primary)}.hero-content p,.opening-hero p,.page-hero p{color:#ffffffd1;font-size:1.14rem;max-width:700px}.eyebrow{display:inline-flex;align-items:center;gap:8px;color:var(--primary);text-transform:uppercase;letter-spacing:.12em;font-size:.76rem;font-weight:850}.hero-actions{display:flex;gap:16px;flex-wrap:wrap;margin-top:34px}.btn{border:0;border-radius:8px;padding:15px 24px;font-weight:800;cursor:pointer;display:inline-flex;align-items:center;justify-content:center;transition:.2s ease;font-size:.98rem}.btn.primary{background:linear-gradient(135deg,#3391ff,#156df0);color:#fff;box-shadow:0 12px 24px #1e7bff47}.btn.primary:hover{transform:translateY(-2px);box-shadow:0 16px 32px #1e7bff57}.btn.ghost{background:transparent;color:var(--white);border:1px solid rgba(255,255,255,.35)}.btn.ghost:hover{background:#ffffff14}.btn:disabled{opacity:.45;cursor:not-allowed;transform:none}.hero-board-card,.opening-summary-card{background:#ffffff0f;border:1px solid rgba(255,255,255,.12);border-radius:var(--radius);padding:28px;box-shadow:var(--shadow)}.hero-board-card h2,.opening-summary-card h2{margin-bottom:8px;color:var(--white)}.hero-board-card p,.opening-summary-card p{color:#ffffffbd}.mini-board{width:100%;aspect-ratio:1;display:grid;grid-template-columns:repeat(4,1fr);border-radius:20px;overflow:hidden;margin-bottom:22px;border:8px solid rgba(255,255,255,.08)}.mini-board span{display:grid;place-items:center;font-size:clamp(2rem,5vw,4rem);min-height:80px}.mini-board span:nth-child(odd){background:#e8eef8;color:#020b18}.mini-board span:nth-child(2n){background:#123157;color:#fff}.features-strip{background:#fff;padding:42px 0;border-bottom:1px solid rgba(15,23,42,.08)}.features-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:0}.feature-item{text-align:center;padding:22px 28px;border-right:1px solid rgba(15,23,42,.08)}.feature-item:last-child{border-right:none}.feature-icon{color:var(--primary);font-size:2.4rem;line-height:1;margin-bottom:14px}.feature-item h3{margin:0 0 8px;font-size:1.08rem;color:var(--text)}.feature-item p{margin:0;color:var(--muted);font-size:.95rem;line-height:1.55}.dark-cta{background:#fff;padding:28px 0 10px}.dark-cta-inner{background:#020b18;color:#fff;border-radius:14px;padding:26px 34px;display:grid;grid-template-columns:auto 1fr auto;align-items:center;gap:24px;box-shadow:0 20px 44px #020b182e}.dark-cta-icon{color:var(--primary);font-size:3rem;line-height:1}.dark-cta-inner h2{margin:0 0 6px;font-size:1.35rem}.dark-cta-inner p{margin:0;color:#ffffffb8;line-height:1.5}.section,.trainer-section,.learning-block{padding:82px 0}.section-heading,.trainer-heading{max-width:760px;margin-bottom:32px}.section-heading h2,.trainer-heading h2,.learning-grid h2{font-size:clamp(2rem,4vw,3.3rem);line-height:1;letter-spacing:-.05em;margin:12px 0 14px}.section-heading p,.trainer-heading p{color:var(--muted)}.cards-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}.opening-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:24px;box-shadow:0 14px 34px #0f172a14;transition:.2s ease}.opening-card:hover{transform:translateY(-5px);box-shadow:0 20px 48px #0f172a21}.opening-badge{display:inline-flex;background:#1e7bff1f;color:var(--primary);font-weight:850;font-size:.75rem;border-radius:999px;padding:7px 10px}.opening-card h3{font-size:1.45rem;margin:18px 0 8px}.opening-moves{color:var(--primary);font-weight:850}.opening-card p{color:var(--muted)}.opening-link{display:inline-block;margin-top:10px;color:var(--primary);font-weight:850}.learning-block{background:#fff}.learning-grid{display:grid;grid-template-columns:.8fr 1.2fr;gap:40px}.learning-points{display:grid;gap:18px}.learning-points article{background:#fff;border-radius:var(--radius);padding:22px;border:1px solid rgba(15,23,42,.08);box-shadow:0 12px 30px #0f172a0f}.learning-points article h3{margin-top:0}.learning-points article p{color:var(--muted)}.page-hero{padding:78px 0;background:linear-gradient(90deg,#020b18fa,#020b18e6 45%,#020b18c2),radial-gradient(circle at center right,rgba(30,123,255,.18),transparent 38%),#020b18}.opening-hero{padding:80px 0 60px;background:linear-gradient(90deg,#020b18fa,#020b18e6 45%,#020b18c2),radial-gradient(circle at center right,rgba(30,123,255,.18),transparent 38%),#020b18}.opening-meta{display:flex;flex-wrap:wrap;gap:10px;margin-top:26px}.opening-meta span{background:#ffffff1a;border:1px solid rgba(255,255,255,.14);border-radius:999px;padding:9px 13px;color:#ffffffd1;font-weight:750}.trainer{display:grid;grid-template-columns:.95fr 1.05fr;gap:28px;align-items:start}.board-panel,.commentary-panel,.content-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);box-shadow:0 18px 48px #0f172a1a}.board-panel{padding:22px}.board{display:grid;grid-template-columns:repeat(8,1fr);aspect-ratio:1;border-radius:18px;overflow:hidden;border:10px solid #020b18;background:#020b18}.square{position:relative;display:grid;place-items:center;font-size:clamp(1.8rem,5vw,3.35rem);line-height:1}.square.light{background:#e8eef8}.square.dark{background:#123157}.square.highlight{outline:4px solid rgba(30,123,255,.9);outline-offset:-4px}.coord{position:absolute;left:5px;bottom:4px;font-size:.62rem;font-weight:800;color:#0f172a6b}.square.dark .coord{color:#ffffff73}.trainer-controls{display:flex;gap:12px;justify-content:center;margin-top:18px;flex-wrap:wrap}.trainer-controls .btn.ghost{color:var(--text);background:#f3f7ff;border-color:#d7e7ff}.commentary-panel{padding:26px}.move-topline{display:flex;justify-content:space-between;gap:14px;align-items:center;margin-bottom:20px;border-bottom:1px solid var(--border);padding-bottom:18px}.move-topline span{background:#eef5ff;color:var(--primary-dark);border-radius:999px;padding:8px 12px;font-weight:850;font-size:.82rem}.move-topline strong{font-size:1.8rem;letter-spacing:-.04em}.info-box{background:var(--surface-soft);border:1px solid var(--border);border-radius:18px;padding:18px;margin-bottom:14px}.info-box h3{margin:0 0 6px;font-size:1rem}.info-box p{margin:0;color:var(--muted)}.moves-strip{display:flex;flex-wrap:wrap;gap:10px;margin-top:22px}.move-pill{border:1px solid var(--border);background:var(--surface);border-radius:999px;padding:10px 14px;cursor:pointer;font-weight:800;color:var(--text)}.move-pill.active{background:var(--primary);color:#fff;border-color:var(--primary)}.content-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}.content-card{padding:24px}.content-card h2{margin-top:0;letter-spacing:-.04em}.content-card li{margin-bottom:10px;color:var(--muted);line-height:1.6}.site-footer{background:#020b18;color:var(--white);padding:54px 0}.footer-grid{display:grid;grid-template-columns:1.4fr .6fr;gap:30px}.site-footer h3,.site-footer h4{color:#fff}.site-footer p,.site-footer a{display:block;color:#ffffffad;margin:8px 0}.site-footer a:hover{color:var(--primary)}@media(max-width:920px){.hero-grid,.opening-hero-grid,.trainer,.learning-grid,.content-grid,.footer-grid{grid-template-columns:1fr}.cards-grid{grid-template-columns:1fr 1fr}.features-grid{grid-template-columns:repeat(2,1fr)}.feature-item{border-right:none;border-bottom:1px solid rgba(15,23,42,.08)}.dark-cta-inner{grid-template-columns:1fr;text-align:center}.dark-cta-inner .btn{width:100%}.nav{display:none}.hero{min-height:auto}}@media(max-width:620px){.cards-grid,.features-grid{grid-template-columns:1fr}.hero,.opening-hero,.page-hero,.section,.trainer-section,.learning-block{padding:58px 0}.board-panel,.commentary-panel{padding:14px}.square{font-size:1.8rem}.coord{display:none}.move-topline{align-items:flex-start;flex-direction:column}.hero-actions{flex-direction:column}.btn{width:100%}}