header{flex-wrap:wrap;gap:16px}header #nav{flex-wrap:wrap;justify-content:center;gap:15px}.hb-language{position:relative;flex-shrink:0;font:600 13px Arial,sans-serif;z-index:50}.hb-language summary{cursor:pointer;list-style:none;background:#101925;color:white;border-radius:24px;padding:12px 15px;white-space:nowrap}.hb-language-options{position:absolute;right:0;top:100%;min-width:155px;background:#fff;color:#17202b;border:1px solid #dce1e7;box-shadow:0 8px 25px #0002;padding:8px;border-radius:7px}.hb-language-options a{display:block;padding:10px}.hb-language-options a:hover,.hb-language-options a[aria-current]{background:#f0f3f7;color:#c60025}[lang=ar] body{font-family:Tahoma,Arial,sans-serif}[lang=ar] h1,[lang=ar] h2,[lang=ar] h3,[lang=ru] h1,[lang=ru] h2,[lang=ru] h3{font-family:Arial,sans-serif;letter-spacing:0;line-height:1.35}[dir=rtl] nav{margin-left:0;margin-right:auto}[dir=rtl] .safety,[dir=rtl] .metric,[dir=rtl] .note{border-left:0;border-right:4px solid #e6002c}[dir=rtl] .hero-gauge{right:auto;left:7%}[dir=rtl] .diagram,[dir=rtl] input[type=number]{direction:ltr}[dir=rtl] .hero-bottom a{margin-left:0;margin-right:auto}.diagram svg{direction:ltr}nav a{white-space:normal;text-align:center}.problem h2,.lesson-card h3{overflow-wrap:anywhere}@media(max-width:800px){header .brand{margin-right:auto}[dir=rtl] header .brand{margin-right:0;margin-left:auto}header img{width:135px}#menu{order:2}.hb-language{order:1}header #nav{order:3;align-items:flex-start;text-align:start}nav a{text-align:start}.hb-language summary{font-size:12px;padding:10px}.hero-bottom a{margin-inline:0!important}}