.buch-hero{background:var(--color-brand-800);color:#fff;padding:3.5rem 0 3rem;position:relative;overflow:hidden}@media(min-width:768px){.buch-hero{padding:5rem 0 4.5rem}}.buch-hero:before{content:"";position:absolute;inset:0;background:radial-gradient(ellipse at 85% 20%,rgba(54,176,254,.22),transparent 55%),radial-gradient(ellipse at 10% 90%,rgba(54,176,254,.1),transparent 50%);pointer-events:none}.buch-hero .container-site{position:relative}.buch-hero__grid{display:grid;gap:2.5rem;align-items:center}@media(min-width:768px){.buch-hero__grid{grid-template-columns:1.1fr .9fr;gap:3.5rem}}.buch-hero__eyebrow{color:var(--color-brand-300);font-size:.8125rem;letter-spacing:.14em;text-transform:uppercase;margin:0 0 1rem;font-weight:700}.buch-hero__text h1{color:#fff;margin:0 0 1.25rem;font-size:clamp(1.75rem,4.5vw,3.25rem);line-height:1.15}.buch-hero__text h1 em{font-style:italic;color:var(--color-brand-300)}.buch-hero__lede{color:#ffffffd9;font-size:clamp(1rem,2vw,1.125rem);line-height:1.55;max-width:46ch;margin:0 0 1.75rem}.buch-hero__actions{display:flex;flex-wrap:wrap;gap:.75rem}.buch-hero__ghost{color:#fff;border-color:#ffffff59}.buch-hero__ghost:hover{background:#ffffff1a;border-color:#ffffff8c}.buch-hero__cover{display:flex;justify-content:center}.buch-hero__cover img{width:100%;max-width:360px;border-radius:14px;box-shadow:0 20px 40px #00000059,0 8px 16px #00000038;transform:perspective(900px) rotateY(-6deg);transition:transform .3s ease}@media(min-width:768px){.buch-hero__cover img{max-width:420px}.buch-hero__cover img:hover{transform:perspective(900px) rotateY(-3deg) translateY(-4px)}}.buch-nav{position:sticky;top:72px;z-index:20;background:var(--color-surface);border-bottom:1px solid var(--color-hairline);box-shadow:0 2px 6px #0026550a}.buch-nav__list{display:flex;gap:.375rem;overflow-x:auto;padding:.6rem 0;margin:0;list-style:none;scrollbar-width:none;-ms-overflow-style:none;-webkit-overflow-scrolling:touch}.buch-nav__list::-webkit-scrollbar{display:none}.buch-nav__list li{flex-shrink:0}.buch-nav__list a{display:inline-block;padding:.35rem .75rem;border:1px solid var(--color-hairline);border-radius:999px;background:var(--color-canvas);color:var(--color-body);font-size:.8125rem;text-decoration:none;white-space:nowrap;transition:color .15s ease,border-color .15s ease,background-color .15s ease}.buch-nav__list a:hover,.buch-nav__list a.is-active{color:var(--color-brand-700);border-color:var(--color-brand-500);background:var(--color-brand-50)}.buch-main{padding:3rem 0 5rem;background:var(--color-canvas)}@media(min-width:768px){.buch-main{padding:4rem 0 6rem}}.buch-content{color:var(--color-body);font-size:1rem;line-height:1.7}.buch-content>*+h2{margin-top:3.5rem}.buch-content h2{counter-increment:buch-chapter;position:relative;margin:0 0 1.5rem;padding:1.1rem 1.25rem 1.1rem 4rem;background:#fff;border:1px solid var(--color-hairline);border-left:4px solid var(--color-brand-500);border-radius:10px;font-size:clamp(1.125rem,2vw,1.375rem);color:var(--color-ink);line-height:1.3;scroll-margin-top:9rem;box-shadow:0 1px 3px #0026550a}.buch-content h2:before{content:counter(buch-chapter,decimal-leading-zero);position:absolute;left:1.1rem;top:50%;transform:translateY(-50%);color:var(--color-brand-500);font-weight:800;font-size:1.25rem;font-variant-numeric:tabular-nums;letter-spacing:.02em}.buch-content{counter-reset:buch-chapter}.buch-content h3{margin:2rem 0 .75rem;font-size:1.125rem;color:var(--color-brand-700);font-weight:700}.buch-content p{margin:.65rem 0}.buch-content a{color:var(--color-brand-600);text-decoration:underline;text-decoration-color:var(--color-brand-200);text-underline-offset:2px;word-break:break-word}.buch-content a:hover{color:var(--color-brand-700);text-decoration-color:var(--color-brand-500)}.buch-content strong{color:var(--color-ink)}.buch-content ul{margin:1rem 0 1rem 1.25rem;list-style:disc}.buch-content li{margin:.4rem 0}.buch-content li>p{margin:.25rem 0}.buch-content hr{border:0;border-top:1px solid var(--color-hairline);margin:3rem 0}.buch-content em{color:var(--color-body)}.buch-content pre{background:#0d1117;color:#e6edf3;padding:1rem 1.1rem;border-radius:10px;overflow-x:auto;margin:1rem 0;font-size:.9em;line-height:1.5}.buch-content code{background:var(--color-brand-50);color:var(--color-brand-700);padding:.15em .4em;border-radius:4px;font-size:.95em}.buch-content pre code{background:transparent;color:inherit;padding:0}