:root {
    --header-height: 72px;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 90;
    background: #06172af5;
    backdrop-filter: blur(12px);
    border-bottom: 1px solid #36516a;
}

.nav-bar {
    max-width: 1340px;
    min-height: var(--header-height);
    margin: auto;
    padding: 0 22px;
    display: flex;
    align-items: center;
    gap: 28px;
}

.brand {
    display: flex;
    flex-direction: column;
    white-space: nowrap;
    line-height: 1.05;
    font-size: 26px;
    font-weight: 900;
    letter-spacing: .11em;
}

    .brand span {
        margin-top: 6px;
        color: #9db8d1;
        font-size: 8px;
        font-weight: 600;
        letter-spacing: .19em;
        line-height: 1.05;
    }

.nav-items {
    display: flex;
    align-items: stretch;
    gap: 1px;
    margin-left: auto;
    min-height: var(--header-height);
}

.nav-item {
    position: relative;
    display: flex;
    align-items: center;
}

    .nav-item > a {
        display: flex;
        align-items: center;
        padding: 17px 12px;
        color: #e3edf8;
        font-size: 13px;
        font-weight: 650;
        white-space: nowrap;
    }

        .nav-item > a:hover,
        .nav-item:focus-within > a {
            color: #5bb5ff;
        }

    .nav-item .arrow {
        margin-left: 5px;
        color: #85a9c8;
        font-size: 10px;
    }

.submenu {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    min-width: 226px;
    padding: 10px;
    background: #0e2b46;
    border: 1px solid #385a79;
    border-radius: 0 0 12px 12px;
    box-shadow: 0 14px 30px #0006;
}

.nav-item:hover .submenu,
.nav-item:focus-within .submenu {
    display: block;
}

.submenu a {
    display: block;
    padding: 9px 12px;
    color: #dfeeff;
    font-size: 13px;
    border-radius: 6px;
}

    .submenu a:hover {
        background: #1b466c;
        color: white;
    }

.nav-items a[aria-current="page"] {
    color: #71c2ff;
}

.nav-contact {
    align-self: center;
    padding: 10px 15px !important;
    background: #147cda;
    border-radius: 7px;
    color: white !important;
}

.menu-toggle {
    display: none;
    margin-left: auto;
    padding: 8px 12px;
    color: white;
    background: #173751;
    border: 1px solid #456783;
    border-radius: 6px;
    font-size: 21px;
    cursor: pointer;
}

@media (max-width: 1080px) {
    .nav-bar {
        flex-wrap: wrap;
    }

    .menu-toggle {
        display: block;
    }

    .nav-items {
        display: none;
        flex-direction: column;
        width: 100%;
        min-height: 0;
        margin: 0;
        padding-bottom: 15px;
    }

        .nav-items.open {
            display: flex;
        }

    .nav-item {
        display: block;
    }

        .nav-item > a {
            display: block;
            width: 100%;
            padding: 10px 12px;
            text-align: left;
        }

        .submenu,
        .nav-item:hover .submenu,
        .nav-item:focus-within .submenu {
            position: static;
            display: block;
            min-width: unset;
            margin: 0 0 8px 10px;
            background: #0e2a43;
            border: 0;
            box-shadow: none;
        }

    .nav-contact {
        display: inline-block !important;
        width: auto !important;
        margin-left: 8px;
    }
}
/* Theme toggle button */
.theme-toggle {
    background: transparent;
    color: #ffffff;
    border: 1px solid #48aaff;
    padding: 9px 14px;
    border-radius: 6px;
    cursor: pointer;
    font-size: 13px;
    font-weight: 600;
    transition: 0.3s ease;
}

    .theme-toggle:hover {
        background: #168fff;
        color: #ffffff;
    }

/* =================================
   LIGHT THEME - BODY ONLY
   HEADER REMAINS DARK
================================= */

body.light-theme {
    background: #f4f6f8;
    color: #172b40;
}

    /* Keep header unchanged in both themes */
    body.light-theme .site-header {
        background: #06172af5;
        border-bottom: 1px solid #36516a;
    }

    body.light-theme .brand {
        color: #ffffff;
    }

        body.light-theme .brand span {
            color: #9db8d1;
        }

    body.light-theme .nav-item > a {
        color: #e3edf8;
    }

        body.light-theme .nav-item > a:hover,
        body.light-theme .nav-item:focus-within > a {
            color: #5bb5ff;
        }

    body.light-theme .nav-item .arrow {
        color: #85a9c8;
    }

    body.light-theme .submenu {
        background: #0e2b46;
        border: 1px solid #385a79;
    }

        body.light-theme .submenu a {
            color: #dfeeff;
        }

            body.light-theme .submenu a:hover {
                background: #1b466c;
                color: white;
            }

    body.light-theme .nav-items a[aria-current="page"] {
        color: #71c2ff;
    }

    body.light-theme .menu-toggle {
        color: white;
        background: #173751;
        border-color: #456783;
    }

    /* Theme button stays consistent */
    body.light-theme .theme-toggle {
        color: #ffffff;
        border-color: #48aaff;
    }

/* =================================
   LIGHT THEME - DARK BODY TEXT
================================= */

body.light-theme {
    background: #f4f6f8;
    color: #172b40;
}

    /* Headings and paragraphs */
    body.light-theme h1,
    body.light-theme h2,
    body.light-theme h3,
    body.light-theme h4,
    body.light-theme p,
    body.light-theme li,
    body.light-theme label,
    body.light-theme span {
        color: #172b40;
    }

    /* Links in page content */
    body.light-theme main a,
    body.light-theme section a {
        color: #0868b2;
    }

    /* Cards and panels */
    body.light-theme .card,
    body.light-theme .content-card,
    body.light-theme .product-card {
        background: #ffffff;
        color: #172b40;
        border-color: #dce3ea;
    }

    /* Input fields */
    body.light-theme input,
    body.light-theme select,
    body.light-theme textarea {
        background: #ffffff;
        color: #172b40;
        border-color: #cbd5df;
    }

    /* Tables */
    body.light-theme table {
        background: #ffffff;
        color: #172b40;
    }

    body.light-theme th {
        background: #e8eef4;
        color: #172b40;
    }

    body.light-theme td {
        color: #172b40;
        border-color: #dce3ea;
    }

/* =====================================
   LIGHT THEME - CONVERT WHITE TEXT
   TO DARK TEXT
===================================== */


/* =========================================
   LIGHT THEME - BODY ONLY
   HEADER ALWAYS REMAINS DARK
========================================= */

body.light-theme {
    background: #f4f6f8;
    color: #172b40;
}

    /* Convert white text in body to dark */
    body.light-theme main,
    body.light-theme main *,
    body.light-theme section,
    body.light-theme section *,
    body.light-theme footer,
    body.light-theme footer * {
        color: #172b40;
    }

        /* Keep links readable */
        body.light-theme main a,
        body.light-theme section a,
        body.light-theme footer a {
            color: #0868b2;
        }

    /* Cards and content panels */
    body.light-theme .card,
    body.light-theme .content-card,
    body.light-theme .product-card {
        background: #ffffff;
        color: #172b40;
        border-color: #dce3ea;
    }

    /* Tables */
    body.light-theme table {
        background: #ffffff;
        color: #172b40;
    }

    body.light-theme th {
        background: #e8eef4;
        color: #172b40;
    }

    body.light-theme td {
        background: #ffffff;
        color: #172b40;
        border-color: #dce3ea;
    }

    /* Input fields */
    body.light-theme input,
    body.light-theme select,
    body.light-theme textarea {
        background: #ffffff;
        color: #172b40;
        border-color: #cbd5df;
    }

    /* =========================================
   HEADER - KEEP DARK IN BOTH THEMES
========================================= */

    body.light-theme .site-header {
        background: #06172af5;
        border-bottom: 1px solid #36516a;
    }

        body.light-theme .site-header .brand {
            color: #ffffff;
        }

            body.light-theme .site-header .brand span {
                color: #9db8d1;
            }

        body.light-theme .site-header .nav-item > a {
            color: #e3edf8;
        }

            body.light-theme .site-header .nav-item > a:hover {
                color: #5bb5ff;
            }

        body.light-theme .site-header .nav-item .arrow {
            color: #85a9c8;
        }

        body.light-theme .site-header .submenu {
            background: #0e2b46;
            border-color: #385a79;
        }

            body.light-theme .site-header .submenu a {
                color: #dfeeff;
            }

                body.light-theme .site-header .submenu a:hover {
                    background: #1b466c;
                    color: #ffffff;
                }

        body.light-theme .site-header .nav-items a[aria-current="page"] {
            color: #71c2ff;
        }

        body.light-theme .site-header .nav-contact {
            color: #ffffff;
        }

        body.light-theme .site-header .menu-toggle {
            color: #ffffff;
            background: #173751;
            border-color: #456783;
        }

        /* Theme button */
        body.light-theme .site-header .theme-toggle {
            color: #ffffff;
            border-color: #48aaff;
        }
/* Force identical typography on every page */
#common-header .brand,
#common-header .brand span {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Arial, sans-serif !important;
}

#common-header .brand {
    font-size: 26px !important;
    font-weight: 900 !important;
    letter-spacing: 0.11em !important;
    line-height: 1.05 !important;
}

#common-header .brand span {
    font-size: 8px !important;
    font-weight: 600 !important;
    letter-spacing: 0.19em !important;
    line-height: 1.05 !important;
}


/* ==========================================
   ZERRO HEADER - MOBILE RESPONSIVE
   Keep desktop design unchanged
========================================== */

/* Tablet and smaller screens */
@media (max-width: 1080px) {

    .nav-bar {
        display: flex;
        flex-wrap: wrap;
        gap: 10px;
    }

    .brand {
        margin-right: auto;
    }

    .menu-toggle {
        display: block;
        margin-left: 0;
    }

    .theme-toggle {
        margin-left: 0;
        padding: 8px 10px;
        font-size: 12px;
    }

    .nav-items {
        display: none;
        flex-direction: column;
        width: 100%;
        order: 3;
    }

        .nav-items.open {
            display: flex;
        }
}


/* ==========================================
   MOBILE PHONE
========================================== */

@media (max-width: 600px) {

    :root {
        --header-height: 64px;
    }

    .nav-bar {
        padding: 9px 14px;
        gap: 8px;
    }

    /* Brand */

    .brand,
    #common-header .brand {
        font-size: 23px !important;
        letter-spacing: 0.10em !important;
        line-height: 1.05 !important;
    }

        .brand span,
        #common-header .brand span {
            margin-top: 5px;
            font-size: 7px !important;
            letter-spacing: 0.17em !important;
        }

    /* Hamburger button */

    .menu-toggle {
        display: block;
        margin-left: auto;
        padding: 6px 12px;
        min-width: 42px;
        min-height: 40px;
        font-size: 21px;
        line-height: 1;
        border-radius: 7px;
    }

    /* Navigation dropdown */

    .nav-items {
        padding: 10px 0 14px;
        gap: 2px;
    }

    .nav-item > a {
        padding: 12px 10px;
        font-size: 14px;
    }

    .submenu {
        padding-left: 12px;
    }

        .submenu a {
            padding: 10px 12px;
            font-size: 13px;
        }

    /* Contact button */

    .nav-contact {
        margin: 10px 10px;
        padding: 10px 16px !important;
    }

    /* Theme button */

    .theme-toggle {
        display: block;
        margin: 8px 10px;
        padding: 10px 14px;
        font-size: 13px;
    }

    /* Prevent horizontal overflow */

    .site-header,
    .nav-bar {
        max-width: 100%;
    }
}


/* Extra small phones */

@media (max-width: 360px) {

    .brand,
    #common-header .brand {
        font-size: 20px !important;
    }

        .brand span,
        #common-header .brand span {
            font-size: 6px !important;
        }

    .nav-bar {
        padding-left: 10px;
        padding-right: 10px;
    }

    .menu-toggle {
        padding: 6px 10px;
    }
}


/* Accessibility */

.menu-toggle:focus-visible,
.theme-toggle:focus-visible,
.nav-item a:focus-visible {
    outline: 2px solid #48aaff;
    outline-offset: 3px;
}


<!DOCTYPE html >
<html lang="en" >
<head >
<meta charset="UTF-8" >
<meta name="viewport" content="width=device-width, initial-scale=1.0" >
<title > ZERRO</title >

<link rel="stylesheet" href="./header.css" >

<title > ZERRO | Home | Motor Control. Integrated.</title >

<style >
:root {
    --navy: #06172a;
    --deep: #0a2036;
    --blue: #168fff;
    --muted: #aebfd2;
    --white: #f6faff;
    --header-height: 72px;
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    background: #07182a;
    color: var(--white);
    font: 16px/1.65 -apple-system, BlinkMacSystemFont, "Segoe UI", Arial, sans-serif;
}

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

/* COMMON HEADER */

section {
    width: 100%;
    scroll-margin-top: var(--header-height);
    padding: 88px 24px;
    border-bottom: 1px solid #17344c;
}

main {
    width: 100%;
    overflow: hidden;
}

.wrap {
    width: 100%;
    max-width: 1340px;
    margin: 0 auto;
}

.hero {
    padding: 0;
    border: 0;
}

    .hero img {
        display: block;
        width: 100%;
        height: 800px;
        max-width: 1600px;
        margin: auto;
        object-fit: contain;
    }

.kicker {
    color: #48aaff;
    letter-spacing: .19em;
    font-size: 12px;
    font-weight: 750;
    text-transform: uppercase;
}

h1, h2, h3, p {
    margin-top: 0;
}

h2 {
    font-size: clamp(32px, 4vw, 52px);
    line-height: 1.13;
    letter-spacing: -.025em;
    margin: 12px 0 22px;
}

h3 {
    font-size: 20px;
    margin-bottom: 9px;
}

p {
    color: #c0d0df;
    max-width: 790px;
}

.lede {
    font-size: 20px;
}

.grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
    margin-top: 32px;
}

.card {
    padding: 26px;
    border: 1px solid #284763;
    background: #102b44;
    border-radius: 12px;
}

    .card p {
        font-size: 15px;
        margin-bottom: 0;
    }

.num {
    color: #4baaff;
    font-size: 12px;
    font-weight: bold;
    letter-spacing: .12em;
}

.light {
    background: #eaf2f9;
    color: #10263a;
}

    .light p {
        color: #425b70;
    }

    .light .card {
        background: #fff;
        border-color: #cee0eb;
    }

    .light .kicker,
    .light .num {
        color: #087ed9;
    }

.art {
    width: 100%;
    display: block;
    object-fit: contain;
    border-radius: 10px;
    background: #fff;
    margin: 30px auto;
    max-height: 600px;
}

.timeline {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
    margin: 25px 0;
}

.milestone {
    border-left: 3px solid #2398ff;
    padding: 6px 18px;
    background: #102b44;
    flex: 1;
    min-width: 180px;
}

    .milestone strong {
        display: block;
        font-size: 20px;
    }

.tag {
    font-size: 12px;
    color: #7ed0ff;
    text-transform: uppercase;
    letter-spacing: .12em;
}

.pill {
    display: inline-block;
    font-size: 12px;
    border: 1px solid #5480a4;
    padding: 4px 10px;
    border-radius: 24px;
    color: #bcd5e9;
    margin-bottom: 8px;
}

.product {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

    .product b {
        font-size: 22px;
    }

    .product small {
        color: #c6d7e8;
    }

.cta {
    display: inline-block;
    padding: 13px 22px;
    background: #148bf0;
    border-radius: 7px;
    font-weight: 700;
    margin-top: 18px;
}

.note {
    font-size: 12px;
    color: #8ea8bf;
    margin-top: 25px;
}

/* HOME PAGE HEADER LINKS AND SECTIONS */

.hero-jump {
    background: #06172a;
    padding: 20px 24px 34px;
    text-align: center;
}

    .hero-jump a,
    .action-link {
        display: inline-block;
        background: #1789ea;
        border-radius: 7px;
        padding: 10px 20px;
        margin: 6px;
        font-size: 14px;
        font-weight: 700;
        color: white;
    }

        .hero-jump a.outline {
            background: transparent;
            border: 1px solid #6b91b3;
        }

.quick-links {
    padding: 53px 24px;
    background: #0a2238;
}

    .quick-links .grid {
        grid-template-columns: repeat(4, 1fr);
    }

    .quick-links .card {
        transition: transform .15s;
        border-color: #375977;
    }

        .quick-links .card:hover {
            transform: translateY(-3px);
            background: #173c5b;
        }

    .quick-links a.card {
        display: block;
    }

    .quick-links .card h3 {
        color: #f4f9ff;
    }

.application-grid {
    grid-template-columns: repeat(3, 1fr);
}

.resource-card {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

    .resource-card .action-link {
        margin: 10px 0 0;
        align-self: flex-start;
        font-size: 12px;
        padding: 8px 12px;
    }

.product-status {
    color: #8bd1ff;
    font-weight: 650;
    font-size: 12px;
}

.page-banner {
    padding: 42px 24px 26px;
    background: #0e2942;
    border-bottom: 1px solid #35516c;
}

    .page-banner p {
        font-size: 24px;
        font-weight: 700;
        color: #fff;
        margin: 6px 0;
    }

.closing-cta {
    background: #0b273f;
}

    .closing-cta h2 {
        font-size: 36px;
    }

.home-feature {
    background: #0a2036;
}

    .home-feature .art {
        max-height: 520px;
    }

/* FOOTER */

.site-footer {
    width: 100%;
    padding: 30px 24px;
    background: #06172a;
    border-top: 1px solid #203b54;
    color: #809cb5;
    font-size: 13px;
}

.footer-content {
    width: 100%;
    max-width: 1340px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    gap: 12px;
}

    .footer-content span {
        line-height: 1.8;
    }

.footer-links {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 22px;
    flex-wrap: wrap;
}

    .footer-links a {
        color: #c6d7e8;
        text-decoration: none;
        white-space: nowrap;
    }

        .footer-links a:hover {
            color: #48aaff;
            text-decoration: underline;
        }

/* RESPONSIVE */

@media (max-width: 1080px) {
    .quick-links .grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 750px) {
    section {
        padding: 55px 18px;
    }

    .hero img {
        width: 100%;
        height: auto;
        min-height: 250px;
        object-fit: contain;
    }

    .wrap {
        width: 100%;
    }

    .grid,
    .quick-links .grid,
    .application-grid {
        grid-template-columns: 1fr;
    }

    .footer-content {
        align-items: center;
        text-align: center;
    }
}


/* ==========================================
   HOME PAGE - LIGHT THEME
   Header remains dark navy
========================================== */

body.light-theme {
    background: #f4f6f8;
    color: #172b40;
}

    /* Main page */
    body.light-theme main {
        background: #f4f6f8;
        color: #172b40;
    }

    body.light-theme section {
        border-bottom-color: #d5dee8;
    }

    /* Hero image section */
    body.light-theme .hero {
        background: #f4f6f8;
    }

    body.light-theme .hero-jump {
        background: #e8eef4;
    }

    /* Headings and text */
    body.light-theme h1,
    body.light-theme h2,
    body.light-theme h3 {
        color: #172b40;
    }

    body.light-theme p {
        color: #526579;
    }

    body.light-theme .kicker {
        color: #0875c9;
    }

    /* Feature cards */
    body.light-theme .card {
        background: #ffffff;
        border-color: #d5dee8;
    }

        body.light-theme .card h3 {
            color: #173d60;
        }

        body.light-theme .card p {
            color: #526579;
        }

    /* Quick links */
    body.light-theme .quick-links {
        background: #e8eef4;
    }

        body.light-theme .quick-links .card {
            background: #ffffff;
            border-color: #cbd7e2;
        }

            body.light-theme .quick-links .card h3 {
                color: #173d60;
            }

            body.light-theme .quick-links .card:hover {
                background: #edf4fa;
            }

    /* Timeline */
    body.light-theme .milestone {
        background: #ffffff;
        border-left-color: #168fff;
    }

        body.light-theme .milestone strong {
            color: #173d60;
        }

    /* Tags and pills */
    body.light-theme .tag {
        color: #0875c9;
    }

    body.light-theme .pill {
        color: #31546f;
        border-color: #9bb3c8;
    }

    /* Product information */
    body.light-theme .product small {
        color: #526579;
    }

    body.light-theme .product-status {
        color: #0875c9;
    }

    /* Artwork */
    body.light-theme .art {
        background: #ffffff;
    }

    /* Page banner */
    body.light-theme .page-banner {
        background: #e8eef4;
        border-color: #d5dee8;
    }

        body.light-theme .page-banner p {
            color: #173d60;
        }

    /* Closing CTA */
    body.light-theme .closing-cta {
        background: #e8eef4;
    }

        body.light-theme .closing-cta h2 {
            color: #173d60;
        }

    /* Home feature */
    body.light-theme .home-feature {
        background: #f4f6f8;
    }

    /* CTA buttons */
    body.light-theme .cta,
    body.light-theme .action-link,
    body.light-theme .hero-jump a {
        background: #0875c9;
        color: #ffffff;
    }

        body.light-theme .hero-jump a.outline {
            background: transparent;
            border-color: #0875c9;
            color: #0875c9;
        }

    /* Footer */
    body.light-theme .site-footer {
        background: #e8eef4;
        color: #40566b;
        border-top-color: #d5dee8;
    }

    body.light-theme .footer-content span {
        color: #40566b;
    }

    body.light-theme .footer-links a {
        color: #0868b2;
    }

        body.light-theme .footer-links a:hover {
            color: #0875c9;
        }

    /* Header ALWAYS remains dark */
    body.light-theme .site-header {
        background: #06172af5;
        border-bottom: 1px solid #36516a;
    }

        body.light-theme .site-header .brand {
            color: #ffffff;
        }

            body.light-theme .site-header .brand span {
                color: #9db8d1;
            }

        body.light-theme .site-header .nav-item > a {
            color: #e3edf8;
        }

        body.light-theme .site-header .submenu {
            background: #0e2b46;
        }

            body.light-theme .site-header .submenu a {
                color: #dfeeff;
            }

        body.light-theme .site-header .theme-toggle {
            color: #ffffff;
        }


.hero img {
    display: block;
    width: 100%;
    height: 900px;
    max-width: 1600px;
    max-height: 800px;
    margin: auto;
    object-fit: contain;
}

@media (max-width: 750px) {
    .hero img {
        width: 100%;
        height: auto;
        max-height: none;
        min-height: 0;
        object-fit: contain;
    }

    .hero {
        padding: 0;
    }
}

/* COMPACT FOOTER FOR MOBILE */
@media (max-width: 750px) {
    .site-footer

{
    padding: 16px 14px;
    font-size: 11px;
}

.footer-content {
    gap: 7px;
    line-height: 1.4;
}

    .footer-content span {
        line-height: 1.5;
        font-size: 11px;
    }

.footer-links {
    gap: 16px;
}

    .footer-links a {
        font-size: 11px;
    }
}