.header{position:sticky;top:0;z-index:var(--z-header);display:flex;align-items:center;gap:var(--space-24);padding-inline:var(--gutter);padding-block:1.15rem;transition:background-color var(--dur-mid) var(--ease-out-quart),box-shadow var(--dur-mid) var(--ease-out-quart),border-color var(--dur-mid) var(--ease-out-quart),padding-block var(--dur-mid) var(--ease-out-quart);border-bottom:1px solid transparent}.header.is-transparent{background:transparent;box-shadow:none}.header.is-solid{padding-block:.55rem;background:color-mix(in oklch,var(--surface) 86%,transparent);backdrop-filter:blur(14px) saturate(1.4);-webkit-backdrop-filter:blur(14px) saturate(1.4);border-bottom-color:var(--hairline);box-shadow:var(--shadow-rest)}.header-brand{display:inline-flex;align-items:center;gap:var(--space-12);margin-right:auto;padding:0;background:none;border:none;cursor:pointer;text-align:left}.header-logo{width:48px;height:auto;flex:none;transform-origin:left center;transition:transform var(--dur-mid) var(--ease-out-quart)}.header.is-solid .header-logo{transform:scale(.88)}.header-text{display:flex;flex-direction:column;line-height:1.2}.header-title{font-size:1.0625rem;font-weight:700;color:var(--ink);letter-spacing:-.01em}.header-subtitle{font-size:.78rem;font-weight:500;color:var(--muted);overflow:hidden;max-height:1.4em;opacity:1;transition:max-height var(--dur-mid) var(--ease-out-quart),opacity var(--dur-fast) linear}.header.is-solid .header-subtitle{max-height:0;opacity:0}.header-nav{display:flex;align-items:center;gap:var(--space-12)}.header-donate{margin-left:var(--space-8);padding:.6rem 1.4rem}.hamburger{display:none;flex-direction:column;gap:5px;background:none;border:none;cursor:pointer;padding:8px}.hamburger span{width:25px;height:2.5px;background:var(--ink);border-radius:var(--r-pill);transition:transform var(--dur-mid) var(--ease-out-quart),opacity var(--dur-fast) linear;transform-origin:center}.hamburger.active span:nth-child(1){transform:rotate(45deg) translate(6px,7px)}.hamburger.active span:nth-child(2){opacity:0}.hamburger.active span:nth-child(3){transform:rotate(-45deg) translate(6px,-7px)}.mobile-menu{display:none;position:absolute;top:100%;left:0;right:0;z-index:var(--z-menu);flex-direction:column;background:var(--surface);border-bottom:1px solid var(--hairline);box-shadow:var(--shadow-hover);padding:var(--space-8) var(--gutter) var(--space-24)}.mobile-menu-item{text-align:left;background:none;border:none;cursor:pointer;padding:14px 4px;font-size:1.05rem;font-weight:500;color:var(--ink);border-bottom:1px solid var(--hairline);transition:color var(--dur-fast) linear;animation:menuItemIn .32s var(--ease-out-expo) both;animation-delay:calc(var(--i, 0) * 40ms)}.mobile-menu-item:last-of-type{border-bottom:none}.mobile-menu-item:hover{color:var(--research-teal-deep)}.mobile-menu-item[aria-current=page]{color:var(--research-teal-deep);font-weight:600}.mobile-donate{margin-top:var(--space-16);justify-content:center}@keyframes menuItemIn{0%{opacity:0;transform:translateY(-6px)}to{opacity:1;transform:none}}@media(max-width:820px){.header{padding-block:.7rem}.header.is-solid{padding-block:.55rem}.header-subtitle,.header-nav{display:none}.hamburger,.mobile-menu{display:flex}}@media(max-width:420px){.header-title{font-size:.98rem}.header-logo{width:40px}}@media(prefers-reduced-motion:reduce){.mobile-menu-item{animation:none}}