:root {
    --secnn-primary: #0891b2;
    --secnn-primary-dark: #0e7490;
    --secnn-focus: rgba(8, 145, 178, 0.2);
}

html { scroll-behavior: smooth; }

body { text-rendering: optimizeLegibility; }

img, svg, video, canvas { max-width: 100%; }

button, input, select, textarea { font: inherit; }

button, a, input, select, textarea { -webkit-tap-highlight-color: transparent; }

:where(a, button, input, select, textarea):focus-visible {
    outline: 3px solid var(--secnn-focus);
    outline-offset: 2px;
}

.secnn-page-nav {
    position: relative;
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    width: min(1180px, calc(100% - 2rem));
    margin: 0 auto 1rem;
    padding-top: 1rem;
    font-family: "Segoe UI", "Noto Sans SC", system-ui, sans-serif;
}

.secnn-page-nav__brand,
.secnn-page-nav__home {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    min-height: 40px;
    padding: 0.55rem 0.8rem;
    border-radius: 10px;
    text-decoration: none;
    line-height: 1;
}

.secnn-page-nav__brand {
    color: inherit;
    font-weight: 800;
    letter-spacing: 0.01em;
}

.secnn-page-nav__home {
    color: #fff;
    background: linear-gradient(135deg, var(--secnn-primary), #2563eb);
    box-shadow: 0 6px 16px rgba(8, 145, 178, 0.2);
    font-weight: 700;
}

.secnn-page-nav__home:hover { transform: translateY(-1px); }

.secnn-page-note {
    width: min(1180px, calc(100% - 2rem));
    margin: 1.25rem auto;
    padding: 0.85rem 1rem;
    color: #475569;
    background: #f8fafc;
    border: 1px solid #e2e8f0;
    border-radius: 10px;
    font: 0.9rem/1.6 "Segoe UI", "Noto Sans SC", system-ui, sans-serif;
}

@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        scroll-behavior: auto !important;
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

@media (max-width: 640px) {
    .secnn-page-nav { width: calc(100% - 1rem); padding-top: 0.5rem; }
    .secnn-page-nav__brand { padding-left: 0.35rem; }
    .secnn-page-nav__home { min-height: 38px; }
}