:root {
    --bg-dark: #0b1220;
    --bg-light: #f4f7fa;
    --glass-bg-dark: rgba(255, 255, 255, 0.06);
    --glass-bg-light: rgba(0, 0, 0, 0.04);
    --accent: #6bb6ff;
    --accent-hover: #3a8ee6;
    --text-light: #eaf3ff;
    --text-dark: #1a1a1a;
    --radius: 12px;
    --transition: .3s ease;
}

/* Base */
body {
    margin: 0;
    padding: 0;
    font-family: Inter, "Segoe UI", Roboto, Arial, sans-serif;
    color: var(--text-light);
    background: var(--bg-dark);
    overflow-x: hidden;
}

body.theme-light {
    background: var(--bg-light);
    color: var(--text-dark);
}

a {
    color: var(--accent);
    text-decoration: none;
}

a:hover {
    filter: brightness(1.1);
}

/* Container */
.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 24px;
}

/* Topbar */
.topbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    backdrop-filter: saturate(120%) blur(10px);
    background: var(--glass-bg-dark);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    z-index: 100;
}

body.theme-light .topbar {
    background: var(--glass-bg-light);
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

.topbar .container {
    display: flex;
    align-items: center;
    gap: 16px;
}

.logo {
    font-weight: 800;
    font-size: 20px;
    color: inherit;
    text-decoration: none;
}

.nav {
    margin-left: auto;
    display: flex;
    gap: 16px;
}

.nav a {
    padding: 8px;
    border-radius: 8px;
    transition: var(--transition);
}

.nav a:hover {
    background: rgba(255, 255, 255, 0.04);
}

.header-actions {
    display: flex;
    gap: 12px;
    align-items: center;
}

.menu-toggle {
    display: none;
    background: none;
    border: 0;
    color: inherit;
    font-size: 20px;
    cursor: pointer;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 16px;
    border-radius: 10px;
    border: 1px solid transparent;
    text-decoration: none;
    cursor: pointer;
    transition: var(--transition);
}

.btn-primary {
    background: linear-gradient(180deg, var(--accent), var(--accent-hover));
    color: #fff;
    box-shadow: 0 6px 20px rgba(36, 125, 255, 0.18);
}

.btn-outline {
    background: transparent;
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: inherit;
}

.btn-ghost {
    background: transparent;
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: inherit;
}

/* Hero */
.hero {
    padding-top: 120px;
    padding-bottom: 60px;
    position: relative;
}

.hero-inner {
    display: flex;
    align-items: center;
    gap: 40px;
    flex-wrap: wrap;
}

.hero-left {
    flex: 1;
    min-width: 300px;
}

.hero-right {
    flex: 1;
    min-width: 300px;
}

.hero h1 {
    font-size: 36px;
    margin-bottom: 12px;
}

.lead {
    color: rgba(234, 243, 255, 0.8);
    margin-bottom: 18px;
    max-width: 48ch;
}

.device-mockup {
    position: relative;
    width: 360px;
    height: 600px;
    border-radius: 28px;
    background: var(--glass-bg-dark);
    backdrop-filter: blur(12px);
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.6);
    overflow: hidden;
    border: 1px solid rgba(255, 255, 255, 0.05);
    margin: auto;
}

body.theme-light .device-mockup {
    background: var(--glass-bg-light);
    box-shadow: 0 20px 60px rgba(0, 0, 0.25);
    border: 1px solid rgba(0, 0, 0, 0.1);
}

.screen {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 18px;
    transition: transform .6s cubic-bezier(.2, .9, .2, 1);
}

.screen img {
    width: 100%;
    height: auto;
    border-radius: 12px;
}

.hero-wave {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 120px;
}

/* Sections */
.section {
    padding: 56px 0;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 18px;
    margin-top: 24px;
}

.feature-card {
    background: var(--glass-bg-dark);
    backdrop-filter: blur(6px);
    border-radius: 12px;
    padding: 18px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: var(--transition);
}

body.theme-light .feature-card {
    background: var(--glass-bg-light);
    border: 1px solid rgba(0, 0, 0, 0.1);
}

.feature-card .icon {
    font-size: 28px;
    margin-bottom: 10px;
}

/* Releases list */
.releases-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-top: 18px;
}

.releases-list a {
    padding: 12px;
    border-radius: 10px;
    background: var(--glass-bg-dark);
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: var(--transition);
}

body.theme-light .releases-list a {
    background: var(--glass-bg-light);
    border: 1px solid rgba(0, 0, 0, 0.1);
}

.releases-list a:hover {
    background: linear-gradient(180deg, var(--accent), var(--accent-hover));
    color: #fff;
}

/* Download cards */
.download-cards {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
    margin-top: 18px;
}

.dl-card {
    flex: 1;
    min-width: 220px;
    background: var(--glass-bg-dark);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    padding: 16px;
}

body.theme-light .dl-card {
    background: var(--glass-bg-light);
    border: 1px solid rgba(0, 0, 0, 0.1);
}

/* Contact */
.contact-section .contact-grid {
    display: grid;
    grid-template-columns: 1fr 320px;
    gap: 24px;
    margin-top: 18px;
}

.card.glass {
    background: var(--glass-bg-dark);
    backdrop-filter: blur(8px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    padding: 16px;
}

body.theme-light .card.glass {
    background: var(--glass-bg-light);
    border: 1px solid rgba(0, 0, 0, 0.1);
}

label {
    display: block;
    margin-bottom: 10px;
    color: rgba(234, 243, 255, 0.8);
}

body.theme-light label {
    color: rgba(26, 26, 26, 0.8);
}

input,
textarea {
    width: 100%;
    padding: 10px;
    border-radius: 8px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    background: rgba(0, 0, 0, 0.25);
    color: var(--text-light);
    outline: none;
    transition: var(--transition);
}

body.theme-light input,
body.theme-light textarea {
    background: rgba(255, 255, 255, 0.75);
    color: var(--text-dark);
    border: 1px solid rgba(0, 0, 0, 0.1);
}

.form-actions {
    display: flex;
    gap: 8px;
    align-items: center;
    margin-top: 8px;
}

.form-result {
    margin-top: 10px;
    color: rgba(234, 243, 255, 0.8);
}

/* Footer */
.site-footer {
    padding: 24px 0;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    margin-top: 24px;
}

body.theme-light .site-footer {
    border-top: 1px solid rgba(0, 0, 0, 0.1);
}

.site-footer .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: rgba(234, 243, 255, 0.7);
}

body.theme-light .site-footer .container {
    color: rgba(26, 26, 26, 0.6);
}

/* Responsive */
@media(max-width:900px) {
    .hero-inner {
        flex-direction: column-reverse;
        align-items: flex-start;
    }

    .hero-right {
        width: 100%;
    }

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

    .nav {
        display: none;
    }

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

    .device-mockup {
        width: 92%;
        height: auto;
    }
}