/* Nutrx site header — ported from the existing marketing site, made self-contained.
   All rules are scoped under `header` so they never leak into the legal pages or
   the hero/feature styles. Colors come from the design tokens in style.css, so the
   header themes correctly with both the system setting and the manual theme toggle. */

header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: color-mix(in srgb, var(--bg) 82%, transparent);
    backdrop-filter: saturate(180%) blur(20px);
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow);
}

header nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0.85rem 5%;
    position: relative;
}

header .nav-left { display: flex; align-items: center; gap: 3rem; }

header .logo {
    display: flex;
    align-items: center;
    gap: 0.55rem;
    font-size: 1.4rem;
    font-weight: 800;
    letter-spacing: -0.02em;
    color: var(--text);
    text-decoration: none;
    transition: transform .3s ease, opacity .3s ease;
}
header .logo:hover { transform: translateY(-2px); opacity: .85; text-decoration: none; }
header .logo-icon { width: 30px; height: 30px; border-radius: 7px; }

header .nav-links { display: flex; list-style: none; gap: 2rem; align-items: center; margin: 0; padding: 0; }
header .nav-links a {
    color: var(--text-soft);
    text-decoration: none;
    font-size: 0.95rem;
    padding: 0.55rem 1rem;
    border-radius: 25px;
    transition: all .3s ease;
}
header .nav-links a:hover {
    color: var(--brand);
    background: color-mix(in srgb, var(--brand) 10%, transparent);
    transform: translateY(-2px);
    text-decoration: none;
}

header .nav-right { display: flex; gap: 1rem; align-items: center; }

/* Language toggle (EN / PT / ES) */
header .language-toggle {
    display: inline-flex;
    align-items: center;
    gap: 2px;
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 3px;
}
header .lang-btn {
    border: none;
    background: transparent;
    padding: 3px;
    cursor: pointer;
    border-radius: 6px;
    line-height: 0;
    transition: background 0.2s ease;
}
header .lang-btn .flag {
    width: 20px;
    height: 20px;
    border-radius: 4px;
    object-fit: cover;
    display: block;
    opacity: 0.5;
    transition: opacity 0.2s ease, box-shadow 0.2s ease;
}
header .lang-btn:hover .flag { opacity: 0.85; }
header .lang-btn.active { background: color-mix(in srgb, var(--brand) 14%, transparent); }
header .lang-btn.active .flag { opacity: 1; box-shadow: 0 0 0 1.5px var(--brand); }
@media (max-width: 480px) {
    header .nav-right { gap: 0.6rem; }
    header .lang-btn .flag { width: 18px; height: 18px; }
}

/* "Get the App" button (matches the marketing site's pink CTA) */
header .btn-signup {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 0.7rem 1.4rem;
    border-radius: 12px;
    font-size: 0.95rem;
    font-weight: 600;
    color: #fff;
    background: var(--brand);
    border: 2px solid var(--brand);
    text-decoration: none;
    transition: all .3s ease;
}
header .btn-signup:hover {
    background: var(--brand-dark);
    border-color: var(--brand-dark);
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(255, 107, 157, 0.4);
    text-decoration: none;
}
header .btn-signup .download-icon { width: 16px; height: 16px; flex-shrink: 0; filter: brightness(0) invert(1); }

/* Theme toggle */
header .theme-toggle {
    width: 40px; height: 40px;
    border: none; background: transparent; border-radius: 8px;
    display: flex; align-items: center; justify-content: center;
    cursor: pointer; color: var(--text-soft); transition: all .3s ease;
}
header .theme-toggle:hover {
    background: color-mix(in srgb, var(--brand) 10%, transparent);
    color: var(--brand); transform: translateY(-2px);
}
header .theme-toggle-slider {
    width: 20px; height: 20px; border-radius: 50%;
    border: 2px solid currentColor; position: relative; overflow: hidden;
}
header .theme-toggle-slider::before {
    content: ""; position: absolute; top: 0; left: 0;
    width: 50%; height: 100%; background: currentColor; transition: all .3s ease;
}
:root[data-theme="dark"] header .theme-toggle-slider::before { left: 50%; }
@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) header .theme-toggle-slider::before { left: 50%; }
}

/* Mobile hamburger */
header .mobile-menu-toggle {
    display: none; flex-direction: column; justify-content: center; align-items: center;
    width: 40px; height: 40px; background: none; border: none; cursor: pointer;
    padding: 8px; border-radius: 8px; transition: all .3s ease;
}
header .mobile-menu-toggle:hover { background: color-mix(in srgb, var(--brand) 10%, transparent); }
header .hamburger-line {
    width: 20px; height: 2px; background: var(--text-soft);
    margin: 2px 0; transition: all .3s ease; transform-origin: center;
}
header .mobile-menu-toggle.active .hamburger-line:nth-child(1) { transform: rotate(45deg) translate(4px, 4px); }
header .mobile-menu-toggle.active .hamburger-line:nth-child(2) { opacity: 0; }
header .mobile-menu-toggle.active .hamburger-line:nth-child(3) { transform: rotate(-45deg) translate(4px, -4px); }

/* Mobile nav drawer */
header .mobile-nav {
    display: none; position: absolute; top: 100%; left: 0; right: 0;
    background: color-mix(in srgb, var(--bg) 94%, transparent);
    backdrop-filter: saturate(180%) blur(20px);
    border-top: 1px solid var(--border); box-shadow: var(--shadow);
    z-index: 999; opacity: 0; transform: translateY(-10px); transition: all .3s ease;
}
header .mobile-nav.active { display: block; opacity: 1; transform: translateY(0); }
header .mobile-nav-content { padding: 1.2rem 5%; max-width: 1200px; margin: 0 auto; }
header .mobile-nav-links { list-style: none; padding: 0; margin: 0; }
header .mobile-nav-links a {
    display: block; padding: 1rem 0; color: var(--text); text-decoration: none;
    font-size: 1.1rem; font-weight: 500; border-bottom: 1px solid var(--border); transition: all .3s ease;
}
header .mobile-nav-links a:hover { color: var(--brand); padding-left: 0.5rem; text-decoration: none; }
header .mobile-nav-links li:last-child a { border-bottom: none; }
header .mobile-get-app { margin-top: 1rem; padding-top: 1rem; border-top: 1px solid var(--border); }
header .mobile-app-btn { width: 100%; justify-content: center; }

/* Offset anchored sections so the fixed header doesn't cover them */
#features, #plus, #download { scroll-margin-top: 90px; }

/* Legal/doc pages use the fixed header too — clear it + offset in-page anchors */
.doc { padding-top: 5.5rem; }
.doc h2 { scroll-margin-top: 90px; }

/* Pin the footer to the bottom of the viewport on short doc pages (e.g. licenses) */
body:has(.doc) { display: flex; flex-direction: column; min-height: 100vh; }
body:has(.doc) .doc { flex: 1 0 auto; width: 100%; }
body:has(.doc) .site-footer { flex-shrink: 0; }

/* Responsive */
@media (max-width: 768px) {
    header .desktop-nav, header .desktop-only { display: none !important; }
    header .mobile-menu-toggle { display: flex; }
}