.tut-hero{position:relative;overflow:hidden;border-radius:20px;padding:30px 32px;background:radial-gradient(900px 300px at 85% -20%,rgba(79,70,229,.18),transparent 60%),radial-gradient(700px 260px at -10% 110%,rgba(14,165,233,.16),transparent 60%),linear-gradient(135deg,#ffffff,#f5f6ff);border:1px solid var(--border);box-shadow:var(--shadow)}.tut-hero h1{margin:8px 0 6px;font-size:28px;letter-spacing:-.02em}.tut-hero .tut-tagline{margin:0 0 14px;color:var(--text-secondary);font-size:15px}.tut-badges{display:flex;flex-wrap:wrap;gap:8px}.tut-badge{display:inline-flex;align-items:center;gap:6px;font-size:12.5px;font-weight:700;padding:4px 11px;border-radius:999px;background:var(--primary-soft);color:var(--primary)}.tut-badge.neutral{background:var(--bg-soft);color:var(--text-secondary)}.tut-badge.green{background:var(--success-soft);color:var(--success)}.tut-back{display:inline-flex;align-items:center;gap:6px;font-size:13.5px;font-weight:600;color:var(--text-secondary)}.tut-back:hover{color:var(--primary)}.tut-progress-wrap{position:-webkit-sticky;position:sticky;top:62px;z-index:15;background:rgba(246,247,251,.92);-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);padding:10px 0;margin:18px 0 0}.tut-progress-bar{height:6px;border-radius:99px;background:var(--bg-soft);overflow:hidden}.tut-progress-fill{height:100%;border-radius:99px;background:linear-gradient(90deg,var(--primary),var(--accent));transition:width .4s ease}.tut-progress-label{display:flex;justify-content:space-between;font-size:12px;color:var(--text-muted);margin-bottom:6px}.tut-layout{display:grid;grid-template-columns:240px minmax(0,1fr);grid-gap:26px;gap:26px;align-items:start;margin-top:8px}.tut-sidebar{position:-webkit-sticky;position:sticky;top:140px;background:var(--surface);border:1px solid var(--border);border-radius:16px;padding:12px;box-shadow:var(--shadow-sm)}.tut-sidebar-title{font-size:12px;font-weight:800;letter-spacing:.08em;text-transform:uppercase;color:var(--text-muted);padding:4px 8px 10px}.tut-nav-item{display:flex;align-items:center;gap:10px;width:100%;text-align:left;border:0;background:transparent;color:var(--text-secondary);font-size:13px;font-weight:600;padding:9px 10px;border-radius:10px;cursor:pointer;transition:background .15s ease,color .15s ease}.tut-nav-item:hover{background:var(--bg-soft)}.tut-nav-item.active{background:var(--primary-soft);color:var(--primary)}.tut-nav-num{flex:0 0 22px;height:22px;display:inline-flex;align-items:center;justify-content:center;border-radius:7px;font-size:11.5px;font-weight:800;background:var(--bg-soft);color:var(--text-muted)}.tut-nav-item.active .tut-nav-num{background:var(--primary);color:#fff}.tut-nav-item.done .tut-nav-num{background:var(--success);color:#fff}.tut-steps{display:flex;flex-direction:column;gap:22px}.tut-step,.tut-steps{scroll-margin-top:130px}.tut-step{background:var(--surface);border:1px solid var(--border);border-radius:18px;padding:24px;box-shadow:var(--shadow-sm)}.tut-step-head{display:flex;align-items:center;gap:12px;margin-bottom:10px}.tut-step-num{flex:0 0 34px;height:34px;display:inline-flex;align-items:center;justify-content:center;border-radius:11px;background:linear-gradient(135deg,var(--primary),var(--accent));color:#fff;font-size:15px;font-weight:800;box-shadow:0 4px 12px rgba(79,70,229,.25)}.tut-step h2{margin:0;font-size:17px}.tut-step .tut-step-desc{margin:0 0 16px;color:var(--text-secondary);font-size:14.5px;line-height:1.7}.tut-links{display:flex;flex-wrap:wrap;gap:10px;margin:0 0 16px}.tut-media{margin:0 0 6px}.tut-media img,.tut-media video{width:100%;max-height:520px;object-fit:contain;border-radius:14px;background:#0d1120;border:1px solid var(--border);cursor:zoom-in}.tut-media video{cursor:default;max-height:560px}.tut-media-caption{font-size:12.5px;color:var(--text-muted);text-align:center;margin-top:6px}.tut-callout{border-radius:12px;padding:13px 15px;margin-top:16px;font-size:13.5px;line-height:1.65}.tut-callout strong{display:block;margin-bottom:3px;font-size:13px}.tut-callout.info{background:var(--primary-soft);color:#3f3a99}.tut-callout.warning{background:var(--warning-soft);color:#96590a}.tut-callout.success{background:var(--success-soft);color:#12683a}.tut-callout img{max-width:220px;border-radius:10px;border:1px solid rgba(0,0,0,.08);margin-top:8px;cursor:zoom-in}.tut-step-nav{display:flex;justify-content:space-between;gap:12px;margin-top:6px}.tut-info-card{background:var(--surface);border:1px solid var(--border);border-radius:18px;padding:20px 24px;box-shadow:var(--shadow-sm)}.tut-info-card h3{margin:0 0 12px;font-size:15px}.tut-info-card ul{margin:0;padding-left:20px;color:var(--text-secondary);font-size:14px;line-height:1.9}.tut-lightbox{position:fixed;inset:0;z-index:100;background:rgba(8,10,22,.82);display:flex;align-items:center;justify-content:center;padding:28px;cursor:zoom-out;animation:tut-fade .18s ease}.tut-lightbox img{max-width:min(92vw,760px);max-height:88vh;border-radius:14px;box-shadow:0 20px 60px rgba(0,0,0,.4)}@keyframes tut-fade{0%{opacity:0}to{opacity:1}}.tut-card-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));grid-gap:20px;gap:20px;margin-top:20px}.tut-card{display:flex;flex-direction:column;background:var(--surface);border:1px solid var(--border);border-radius:18px;overflow:hidden;box-shadow:var(--shadow-sm);transition:transform .18s ease,box-shadow .18s ease,border-color .18s ease}.tut-card:hover{transform:translateY(-3px);box-shadow:var(--shadow-lg);border-color:var(--border-strong)}.tut-card-cover{aspect-ratio:4/3;object-fit:cover;background:#0d1120;width:100%}.tut-card-body{padding:16px 18px 18px;display:flex;flex-direction:column;gap:8px;flex:1 1}.tut-card-body h3{margin:0;font-size:16px}.tut-card-body p{margin:0;font-size:13px;color:var(--text-secondary);line-height:1.6;flex:1 1}.tut-card-foot{display:flex;align-items:center;justify-content:space-between;margin-top:4px}@media (max-width:860px){.tut-layout{grid-template-columns:1fr}.tut-sidebar{display:none}.tut-hero{padding:24px 20px}.tut-hero h1{font-size:22px}}