/* ============================================================
   ATHER9 — Infection Prevention. Powered by Data.
   Editorial Swiss-minimalist design system
   ============================================================ */

/* --- Reset & Foundation --- */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --black: #0a0a0a;
    --near-black: #141414;
    --dark: #1a1a1a;
    --charcoal: #2a2a2a;
    --grey-700: #444;
    --grey-500: #777;
    --grey-300: #bbb;
    --grey-200: #ddd;
    --grey-100: #eee;
    --light: #f5f5f3;
    --white: #fafafa;
    --pure-white: #fff;

    --font-display: 'Syne', sans-serif;
    --font-body: 'Outfit', sans-serif;

    --space-xs: 0.5rem;
    --space-sm: 1rem;
    --space-md: 2rem;
    --space-lg: 4rem;
    --space-xl: 6rem;
    --space-2xl: 8rem;

    --nav-height: 64px;
    --max-width: 1200px;

    --ease: cubic-bezier(0.25, 0.46, 0.45, 0.94);
    --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
}

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-body);
    font-size: 1rem;
    font-weight: 400;
    line-height: 1.65;
    color: var(--black);
    background: var(--pure-white);
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

a {
    color: inherit;
    text-decoration: none;
}

ul {
    list-style: none;
}

/* --- Container --- */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-md);
}

/* --- Typography --- */
h1, h2, h3, h4 {
    font-family: var(--font-display);
    font-weight: 700;
    line-height: 1.15;
    letter-spacing: -0.02em;
}

h1 {
    font-size: clamp(2.5rem, 5.5vw, 4.5rem);
    font-weight: 800;
}

h2 {
    font-size: clamp(2rem, 4vw, 3.25rem);
}

h3 {
    font-size: clamp(1.25rem, 2vw, 1.5rem);
    font-weight: 600;
}

/* --- Navigation --- */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--nav-height);
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--grey-200);
    z-index: 1000;
    transition: box-shadow 0.3s var(--ease);
}

.navbar.scrolled {
    box-shadow: 0 1px 20px rgba(0, 0, 0, 0.06);
}

.nav-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: var(--nav-height);
}

.logo {
    font-family: var(--font-display);
    font-size: 1.5rem;
    font-weight: 800;
    letter-spacing: -0.03em;
    color: var(--black);
}

.logo sup {
    font-size: 0.6em;
    vertical-align: super;
    line-height: 0;
}

.logo--footer {
    font-size: 1.75rem;
    color: var(--grey-300);
}

.nav-links {
    display: flex;
    gap: 2.5rem;
    align-items: center;
}

.nav-links a {
    font-family: var(--font-body);
    font-size: 0.875rem;
    font-weight: 400;
    color: var(--grey-700);
    letter-spacing: 0.02em;
    transition: color 0.2s var(--ease);
}

.nav-links a:hover {
    color: var(--black);
}

.cta-link {
    font-weight: 500 !important;
    color: var(--black) !important;
    padding: 0.5rem 1.25rem;
    border: 1.5px solid var(--black);
    border-radius: 2px;
    transition: all 0.2s var(--ease) !important;
}

.cta-link:hover {
    background: var(--black) !important;
    color: var(--pure-white) !important;
}

/* --- Language Switcher --- */
.language-switcher {
    display: flex;
    gap: 2px;
    margin-left: 1rem;
}

.language-switcher a {
    font-family: var(--font-body);
    font-size: 0.75rem;
    font-weight: 500;
    letter-spacing: 0.04em;
    color: var(--grey-500);
    padding: 0.3rem 0.5rem;
    border-radius: 2px;
    transition: all 0.2s var(--ease);
}

.language-switcher a:hover {
    color: var(--black);
}

.language-switcher a.active {
    color: var(--black);
    background: var(--grey-100);
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.mobile-menu-toggle span {
    width: 22px;
    height: 1.5px;
    background: var(--black);
    transition: all 0.3s var(--ease);
}

/* --- Buttons --- */
.btn {
    display: inline-block;
    font-family: var(--font-body);
    font-size: 0.9375rem;
    font-weight: 500;
    padding: 0.875rem 2rem;
    border-radius: 2px;
    transition: all 0.25s var(--ease);
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: var(--black);
    color: var(--pure-white);
}

.btn-primary:hover {
    background: var(--charcoal);
    transform: translateY(-1px);
}

.btn-primary--inverted {
    background: var(--pure-white);
    color: var(--black);
}

.btn-primary--inverted:hover {
    background: var(--grey-100);
    transform: translateY(-1px);
}

.btn-ghost {
    background: transparent;
    color: var(--black);
    border: 1.5px solid var(--grey-200);
}

.btn-ghost:hover {
    border-color: var(--black);
}

/* --- Hero --- */
.hero {
    padding-top: calc(var(--nav-height) + var(--space-xl));
    padding-bottom: var(--space-xl);
}

.hero-eyebrow {
    font-family: var(--font-body);
    font-size: 0.8125rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: var(--grey-500);
    margin-bottom: var(--space-sm);
}

.hero h1 {
    font-size: clamp(3rem, 7vw, 5.5rem);
    margin-bottom: var(--space-md);
    max-width: 900px;
}

.hero-subtitle {
    font-family: var(--font-body);
    font-weight: 600;
    letter-spacing: -0.01em;
}

.hero-sub {
    font-size: 1.125rem;
    line-height: 1.7;
    color: var(--grey-700);
    max-width: 520px;
    margin-bottom: var(--space-md);
}

.hero-actions {
    display: flex;
    gap: var(--space-sm);
    margin-bottom: var(--space-md);
}

.hero-member {
    font-size: 0.8125rem;
    color: var(--grey-500);
}

/* --- Manifesto Strip --- */
.manifesto {
    background: var(--black);
    padding: var(--space-md) 0;
}

.manifesto-text {
    font-family: var(--font-display);
    font-size: clamp(1.25rem, 2.5vw, 1.75rem);
    font-weight: 600;
    color: var(--pure-white);
    text-align: center;
    letter-spacing: -0.01em;
}

.manifesto-text em {
    font-style: italic;
    font-weight: 400;
    color: var(--grey-300);
}

/* --- Sections --- */
.section {
    padding: var(--space-2xl) 0;
}

.section--white {
    background: var(--pure-white);
}

.section--light {
    background: var(--light);
}

.section--dark {
    background: var(--black);
    color: var(--pure-white);
}

.section--accent {
    background: var(--near-black);
    color: var(--pure-white);
}

.section-eyebrow {
    font-family: var(--font-body);
    font-size: 0.75rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.14em;
    color: var(--grey-500);
    margin-bottom: var(--space-sm);
}

.section-eyebrow--light {
    color: var(--grey-300);
}

.section-intro {
    font-size: 1.125rem;
    line-height: 1.7;
    color: var(--grey-700);
    max-width: 680px;
    margin-top: var(--space-sm);
    margin-bottom: var(--space-lg);
}

.text-white {
    color: var(--pure-white);
}

.text-muted {
    color: var(--grey-500) !important;
}

/* --- The Gap --- */
.gap-columns {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-md);
}

.gap-item {
    padding: var(--space-md) 0;
    border-top: 2px solid var(--black);
}

.gap-number {
    font-family: var(--font-display);
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--grey-500);
    display: block;
    margin-bottom: var(--space-sm);
}

.gap-item h3 {
    margin-bottom: 0.75rem;
}

.gap-item p {
    color: var(--grey-700);
    font-size: 0.9375rem;
    line-height: 1.65;
}

/* --- Capabilities --- */
.capabilities-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-md);
}

.capability-card {
    padding: var(--space-md);
    background: var(--pure-white);
    border: 1px solid var(--grey-200);
    border-radius: 4px;
    transition: all 0.3s var(--ease);
}

.capability-card:hover {
    border-color: var(--black);
    transform: translateY(-3px);
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.06);
}

.capability-icon {
    width: 40px;
    height: 40px;
    margin-bottom: var(--space-sm);
    color: var(--black);
}

.capability-icon svg {
    width: 100%;
    height: 100%;
}

.capability-card h3 {
    margin-bottom: 0.75rem;
    font-size: 1.125rem;
}

.capability-card p {
    color: var(--grey-700);
    font-size: 0.9375rem;
    line-height: 1.6;
}

/* --- Layered Model --- */
.layers {
    display: flex;
    flex-direction: column;
    gap: 2px;
    margin-top: var(--space-lg);
}

.layer {
    display: grid;
    grid-template-columns: 240px 1fr;
    gap: var(--space-md);
    padding: var(--space-md) var(--space-md);
    border-radius: 4px;
    align-items: start;
}

.layer--primary {
    background: var(--pure-white);
    color: var(--black);
}

.layer--secondary {
    background: var(--charcoal);
    color: var(--pure-white);
}

.layer--tertiary {
    background: rgba(255, 255, 255, 0.08);
}

.layer--base {
    background: rgba(255, 255, 255, 0.04);
}

.layer-label {
    font-family: var(--font-body);
    font-size: 0.75rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    padding-top: 0.25rem;
    opacity: 0.7;
}

.layer--primary .layer-label {
    color: var(--grey-500);
}

.layer-content h3 {
    margin-bottom: 0.5rem;
}

.layer-content p {
    font-size: 0.9375rem;
    line-height: 1.6;
    opacity: 0.8;
}

/* --- Statistics --- */
.stats-row {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-md);
    margin-bottom: var(--space-lg);
}

.stat {
    padding: var(--space-md) 0;
    border-top: 2px solid var(--black);
}

.stat-number {
    font-family: var(--font-display);
    font-size: clamp(2rem, 3.5vw, 3rem);
    font-weight: 800;
    display: block;
    letter-spacing: -0.02em;
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 0.875rem;
    color: var(--grey-700);
    line-height: 1.5;
}

.outcomes-block {
    max-width: 680px;
    padding: var(--space-md);
    border-left: 3px solid var(--black);
}

.outcomes-block h3 {
    margin-bottom: var(--space-sm);
}

.outcomes-block p {
    color: var(--grey-700);
    margin-bottom: 0.75rem;
}

.outcomes-block p:last-child {
    margin-bottom: 0;
}

/* --- Analytics --- */
.analytics-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-md);
    margin-bottom: var(--space-lg);
}

.analytics-feature {
    padding: var(--space-md);
    border: 1px solid var(--grey-200);
    border-radius: 4px;
    background: var(--pure-white);
    transition: all 0.3s var(--ease);
}

.analytics-feature:hover {
    border-color: var(--black);
}

.analytics-feature h3 {
    margin-bottom: 0.75rem;
    font-size: 1.25rem;
}

.analytics-feature p {
    color: var(--grey-700);
    font-size: 0.9375rem;
    line-height: 1.65;
}

.analytics-cta {
    text-align: center;
    padding: var(--space-lg) 0 0;
}

.analytics-tagline {
    font-family: var(--font-display);
    font-size: clamp(1.5rem, 3vw, 2.25rem);
    font-weight: 700;
    line-height: 1.3;
    letter-spacing: -0.02em;
}

/* --- Protecta --- */
.protecta-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-lg);
    align-items: center;
}

.protecta-text h2 {
    margin-bottom: var(--space-md);
}

.protecta-text p {
    color: var(--grey-700);
    margin-bottom: var(--space-md);
    max-width: 500px;
}

.protecta-badge {
    display: inline-flex;
    flex-direction: column;
    padding: var(--space-sm) var(--space-md);
    border: 2px solid var(--black);
    border-radius: 4px;
}

.protecta-badge span {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--grey-500);
}

.protecta-badge strong {
    font-family: var(--font-display);
    font-size: 1.25rem;
    font-weight: 800;
    letter-spacing: 0.05em;
}

.protecta-image img {
    border-radius: 4px;
}

/* --- Event Block --- */
.event-block {
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
}

.event-block h2 {
    margin-bottom: var(--space-sm);
}

.event-block p {
    font-size: 1.125rem;
    margin-bottom: var(--space-md);
}

/* --- Contact --- */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-lg);
    align-items: start;
}

.contact-text h2 {
    margin-bottom: var(--space-md);
}

.contact-text p {
    color: var(--grey-700);
    max-width: 480px;
    line-height: 1.7;
}

.contact-card {
    background: var(--light);
    padding: var(--space-md);
    border-radius: 4px;
    border: 1px solid var(--grey-200);
}

.contact-person {
    margin-bottom: var(--space-md);
    padding-bottom: var(--space-md);
    border-bottom: 1px solid var(--grey-200);
}

.contact-person h3 {
    margin-bottom: 0.25rem;
}

.contact-role {
    font-size: 0.875rem;
    color: var(--grey-500);
}

.contact-details {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.contact-line {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 0.9375rem;
    color: var(--grey-700);
    transition: color 0.2s var(--ease);
}

.contact-line:hover {
    color: var(--black);
}

.contact-line svg {
    flex-shrink: 0;
    color: var(--grey-500);
}

/* --- Footer --- */
.footer {
    background: var(--black);
    color: var(--grey-500);
    padding: var(--space-xl) 0 var(--space-md);
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: var(--space-lg);
    margin-bottom: var(--space-lg);
}

.footer-brand p {
    font-size: 0.9375rem;
    margin-top: var(--space-sm);
    max-width: 320px;
}

.footer-member {
    font-size: 0.8125rem !important;
    margin-top: 0.5rem !important;
    color: var(--grey-700);
}

.footer-links h4 {
    font-family: var(--font-body);
    font-size: 0.75rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--grey-300);
    margin-bottom: var(--space-sm);
}

.footer-links li {
    margin-bottom: 0.5rem;
}

.footer-links a {
    font-size: 0.875rem;
    color: var(--grey-500);
    transition: color 0.2s var(--ease);
}

.footer-links a:hover {
    color: var(--pure-white);
}

.footer-bottom {
    padding-top: var(--space-md);
    border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.footer-bottom p {
    font-size: 0.8125rem;
    color: var(--grey-700);
}

/* --- Back to Top --- */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 44px;
    height: 44px;
    background: var(--black);
    color: var(--pure-white);
    border: none;
    border-radius: 2px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s var(--ease);
    z-index: 999;
}

.back-to-top:hover {
    background: var(--charcoal);
    transform: translateY(-2px);
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

/* --- Scroll animations --- */
.fade-in {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 0.7s var(--ease-out), transform 0.7s var(--ease-out);
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Stagger children */
.stagger > * {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.5s var(--ease-out), transform 0.5s var(--ease-out);
}

.stagger.visible > *:nth-child(1) { transition-delay: 0s; }
.stagger.visible > *:nth-child(2) { transition-delay: 0.08s; }
.stagger.visible > *:nth-child(3) { transition-delay: 0.16s; }
.stagger.visible > *:nth-child(4) { transition-delay: 0.24s; }

.stagger.visible > * {
    opacity: 1;
    transform: translateY(0);
}

/* --- Imprint --- */
.imprint-content {
    max-width: 740px;
}

.imprint-section {
    margin-bottom: var(--space-lg);
}

.imprint-section h3 {
    margin-bottom: var(--space-sm);
}

.imprint-section h4 {
    font-family: var(--font-body);
    font-size: 1rem;
    font-weight: 600;
    margin-top: var(--space-md);
    margin-bottom: 0.5rem;
}

.imprint-section p {
    color: var(--grey-700);
    line-height: 1.75;
    margin-bottom: 0.75rem;
}

.imprint-section a {
    color: var(--black);
    text-decoration: underline;
    text-underline-offset: 2px;
    transition: color 0.2s var(--ease);
}

.imprint-section a:hover {
    color: var(--grey-500);
}

/* ============================================================
   Responsive
   ============================================================ */

@media (max-width: 1024px) {
    .capabilities-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    :root {
        --nav-height: 56px;
    }

    .nav-links {
        display: none;
        position: absolute;
        top: var(--nav-height);
        left: 0;
        right: 0;
        background: rgba(255, 255, 255, 0.97);
        backdrop-filter: blur(12px);
        flex-direction: column;
        padding: var(--space-md);
        gap: 0;
        border-bottom: 1px solid var(--grey-200);
    }

    .nav-links.active {
        display: flex;
    }

    .nav-links li {
        width: 100%;
        text-align: center;
        padding: 0.75rem 0;
        border-bottom: 1px solid var(--grey-100);
    }

    .nav-links li:last-child {
        border-bottom: none;
        padding-top: var(--space-sm);
    }

    .cta-link {
        display: inline-block !important;
    }

    .mobile-menu-toggle {
        display: flex;
    }

    .mobile-menu-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }

    .mobile-menu-toggle.active span:nth-child(2) {
        opacity: 0;
    }

    .mobile-menu-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(5px, -5px);
    }

    .hero {
        padding-top: calc(var(--nav-height) + var(--space-lg));
        padding-bottom: var(--space-lg);
    }

    .hero-actions {
        flex-direction: column;
    }

    .hero-actions .btn {
        text-align: center;
    }

    .section {
        padding: var(--space-xl) 0;
    }

    .gap-columns {
        grid-template-columns: 1fr;
        gap: 0;
    }

    .gap-item {
        padding: var(--space-md) 0;
    }

    .capabilities-grid {
        grid-template-columns: 1fr;
    }

    .layer {
        grid-template-columns: 1fr;
        gap: var(--space-sm);
    }

    .stats-row {
        grid-template-columns: 1fr;
    }

    .analytics-grid {
        grid-template-columns: 1fr;
    }

    .protecta-grid {
        grid-template-columns: 1fr;
        gap: var(--space-md);
    }

    .protecta-image {
        order: -1;
    }

    .contact-grid {
        grid-template-columns: 1fr;
    }

    .footer-content {
        grid-template-columns: 1fr;
        gap: var(--space-md);
    }
}

@media (max-width: 400px) {
    h1 {
        font-size: 2rem;
    }

    .hero {
        padding-top: calc(var(--nav-height) + var(--space-md));
    }
}