.header{position:fixed;top:0;left:0;right:0;z-index:1000;background-color:var(--color-bg)}.header__content{display:grid;grid-template-columns:repeat(2,minmax(300px,1fr));justify-content:center;gap:var(--spacing-sm);height:80px;position:relative}.header__nav{display:flex;gap:var(--spacing-xl);align-items:center;justify-content:flex-start}.header__list{display:flex;list-style:none;margin:0;padding:0;gap:5rem}.nav-link{font-size:14px;font-weight:500;color:var(--color-black);text-decoration:none;padding:6px 0;letter-spacing:.04em;transition:color .3s;border-bottom:1px solid transparent;padding:0}.nav-link:hover{color:var(--color-blue)}.nav-link--active{border-bottom-color:var(--color-gray);color:var(--color-black)}.burger{display:none;flex-direction:column;justify-content:space-between;width:30px;height:24px;background:0 0;border:none;cursor:pointer;padding:0;gap:4px}.burger-line{display:block;width:100%;height:3px;background-color:#333;border-radius:2px;transition:transform .3s ease,opacity .3s ease}.burger.active .burger-line:nth-child(2){transform:rotate(45deg) translateY(14px);transform-origin:center}.burger.active .burger-line:nth-child(3){opacity:0}.burger.active .burger-line:nth-child(4){transform:rotate(-45deg) translateY(-14px);transform-origin:center}.header__logo{display:flex;justify-content:space-between;align-items:center}.header__logo>a{display:flex;align-items:center;line-height:0}.logo{width:184px;display:block}.logo__text{display:flex;align-items:center;gap:1px;padding-bottom:4px}.logo__text--portal{font-family:var(--font-secondary);font-size:30px;font-weight:600;color:var(--color-blue);letter-spacing:.033em}.logo__text--gpt{font-family:var(--font-secondary);font-size:30px;font-weight:600;color:var(--color-black)}.models-block{position:absolute;bottom:-60px;font-size:14px;font-weight:600;text-transform:uppercase;letter-spacing:1px;background:var(--color-gray-back);width:calc(var(--container-max-width) - var(--container-padding) - var(--container-padding));padding:var(--spacing-sm) var(--spacing-lg);border-radius:0;box-shadow:0 4px 12px rgba(0,0,0,.05);z-index:9;opacity:0;visibility:hidden;transform:translateY(-10px);transition:all .3s cubic-bezier(.4, 0, .2, 1)}.models-block.visible{opacity:1;visibility:visible;transform:translateY(0)}.models-list{display:flex;gap:var(--spacing-sm);justify-content:space-between;list-style:none}.model-item{text-decoration:none;color:var(--color-black);transition:color .2s,text-decoration .2s;margin:0}.model-item:hover{color:var(--color-blue)}.model-item:active,.model-item:focus{color:var(--color-blue)}@media (max-width:1919px){.models-block{width:100%;left:0}}@media (max-width:1379px){.logo{width:160px}.header__list{gap:2rem}}@media (max-width:1115px){.header .header__content{position:relative}.header__content{display:flex;align-items:center}.header__logo{width:100%;height:100%}.burger{display:flex}.header__nav{position:absolute;top:100%;left:-40px;background-color:rgba(246,248,255,.92);backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);width:340px;align-items:flex-start;z-index:1001;opacity:0;visibility:hidden;transform:translateX(-10px);transition:all .3s cubic-bezier(.4, 0, .2, 1)}.header__nav.active{opacity:1;visibility:visible;transform:translateX(0)}.header__list{width:100%;flex-direction:column;gap:0}.header__item{padding:28px 40px;border-bottom:1px solid var(--color-gray)}.header__item:first-child{border-top:1px solid var(--color-gray)}.nav-link{font-size:18px;font-weight:600;text-transform:uppercase}.models-block{display:none!important;visibility:hidden;height:0;opacity:0;pointer-events:none}.neuro-submenu{display:flex;flex-direction:column;gap:var(--spacing-sm);list-style:none;padding-top:var(--spacing-sm)}.neuro-submenu__item{font-size:14px;font-weight:600;text-transform:uppercase;text-decoration:none;color:var(--color-black)}.neuro-submenu__item:hover{color:var(--color-blue)}}@media (max-width:455px){.logo{width:160px}}