*, *::before, *::after { box-sizing: border-box; }

:root {
    --color-bg: #ffffff;
    --color-surface: #f6f8fb;
    --color-text: #121826;
    --color-muted: #4b5563;
    --color-primary: #0b5fff;
    --color-primary-dark: #0847c4;
    --color-accent: #7c3aed;
    --color-accent-2: #06b6d4;
    --color-border: #e5e7eb;
    --radius: 10px;
    --radius-lg: 18px;
    --shadow-sm: 0 1px 2px rgba(16, 24, 40, 0.06);
    --shadow-md: 0 6px 20px rgba(16, 24, 40, 0.08);
    --shadow-lg: 0 20px 45px rgba(16, 24, 40, 0.12);
    --max-width: 1120px;
    --space-1: 0.5rem;
    --space-2: 1rem;
    --space-3: 1.5rem;
    --space-4: 2rem;
    --space-5: 3rem;
    --space-6: 4rem;
    --gradient-brand: linear-gradient(135deg, #0b5fff 0%, #7c3aed 55%, #06b6d4 100%);
}

@media (prefers-color-scheme: dark) {
    :root {
        --color-bg: #0b1020;
        --color-surface: #121a2e;
        --color-text: #e6ebf5;
        --color-muted: #9aa4b8;
        --color-border: #1f2a44;
        --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
        --shadow-md: 0 6px 20px rgba(0, 0, 0, 0.5);
        --shadow-lg: 0 20px 45px rgba(0, 0, 0, 0.6);
    }
}

html { scroll-behavior: smooth; }

body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, "Helvetica Neue", Arial, sans-serif;
    font-size: 16px;
    line-height: 1.6;
    color: var(--color-text);
    background-color: var(--color-bg);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

img { max-width: 100%; height: auto; display: block; }
a { color: var(--color-primary); text-decoration: none; }
a:hover, a:focus { text-decoration: underline; }

:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
    border-radius: 4px;
}

.container {
    width: 100%;
    max-width: var(--max-width);
    margin-inline: auto;
    padding-inline: var(--space-2);
}

.skip-link {
    position: absolute;
    left: -9999px;
    top: 0;
    background: var(--color-primary);
    color: #fff;
    padding: var(--space-1) var(--space-2);
    z-index: 1000;
}
.skip-link:focus { left: var(--space-2); top: var(--space-2); }

.site-header {
    position: sticky;
    top: 0;
    background: color-mix(in srgb, var(--color-bg) 88%, transparent);
    backdrop-filter: saturate(160%) blur(10px);
    -webkit-backdrop-filter: saturate(160%) blur(10px);
    border-bottom: 1px solid var(--color-border);
    z-index: 100;
}

.site-header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-block: var(--space-2);
    gap: var(--space-2);
}

.logo {
    font-weight: 700;
    font-size: 1.25rem;
    background: var(--gradient-brand);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}
.logo:hover { text-decoration: none; }

.nav-toggle {
    display: none;
    background: none;
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 0.5rem 0.75rem;
    cursor: pointer;
    color: var(--color-text);
    font-size: 1rem;
}

.site-nav ul {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    gap: var(--space-3);
}

.site-nav a {
    color: var(--color-text);
    font-weight: 500;
    position: relative;
    padding-block: 0.25rem;
}

.site-nav a::after {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    bottom: -4px;
    height: 2px;
    background: var(--gradient-brand);
    border-radius: 2px;
    transform: scaleX(0);
    transform-origin: left center;
    transition: transform 0.25s ease;
}
.site-nav a:hover { text-decoration: none; }
.site-nav a:hover::after,
.site-nav a:focus-visible::after { transform: scaleX(1); }

.hero {
    position: relative;
    padding-block: var(--space-6);
    background: linear-gradient(180deg, var(--color-surface), var(--color-bg));
    overflow: hidden;
    isolation: isolate;
}

.hero::before,
.hero::after {
    content: "";
    position: absolute;
    z-index: -1;
    border-radius: 50%;
    filter: blur(70px);
    opacity: 0.55;
    pointer-events: none;
    animation: drift 18s ease-in-out infinite alternate;
}
.hero::before {
    top: -120px;
    left: -80px;
    width: 360px;
    height: 360px;
    background: radial-gradient(circle at 30% 30%, #7c3aed, transparent 60%);
}
.hero::after {
    bottom: -140px;
    right: -100px;
    width: 420px;
    height: 420px;
    background: radial-gradient(circle at 70% 70%, #06b6d4, transparent 60%);
    animation-delay: -6s;
}

@keyframes drift {
    0%   { transform: translate3d(0, 0, 0) scale(1); }
    100% { transform: translate3d(40px, 30px, 0) scale(1.08); }
}

.hero-inner {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--space-4);
    align-items: center;
    animation: rise 0.7s ease-out both;
}

@keyframes rise {
    from { opacity: 0; transform: translateY(14px); }
    to   { opacity: 1; transform: translateY(0); }
}

.hero h1 {
    font-size: clamp(2rem, 5vw, 3.25rem);
    line-height: 1.15;
    margin: 0 0 var(--space-2);
    background: var(--gradient-brand);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

.hero p {
    font-size: 1.125rem;
    color: var(--color-muted);
    margin: 0 0 var(--space-3);
    max-width: 60ch;
}

.btn {
    display: inline-block;
    padding: 0.75rem 1.25rem;
    border-radius: var(--radius);
    font-weight: 600;
    cursor: pointer;
    border: 1px solid transparent;
    transition: background-color 0.15s ease, transform 0.05s ease, box-shadow 0.2s ease;
}
.btn:hover { text-decoration: none; }
.btn:active { transform: translateY(1px); }

.btn-primary {
    background: var(--gradient-brand);
    background-size: 180% 180%;
    background-position: 0% 50%;
    color: #fff;
    box-shadow: var(--shadow-md);
    transition: background-position 0.4s ease, box-shadow 0.2s ease, transform 0.05s ease;
}
.btn-primary:hover {
    background-position: 100% 50%;
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background: transparent;
    color: var(--color-text);
    border-color: var(--color-border);
}
.btn-secondary:hover { background: var(--color-surface); }

.cta-row {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-2);
}

section { padding-block: var(--space-5); }
section h2 {
    font-size: clamp(1.5rem, 3vw, 2rem);
    margin: 0 0 var(--space-3);
}

.section-head { margin-bottom: var(--space-3); }
.section-head > h2 { margin: 0 0 var(--space-1); }
.section-head > p { color: var(--color-muted); max-width: 65ch; margin: 0; }

.features-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--space-3);
}

.feature {
    position: relative;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-3);
    box-shadow: var(--shadow-sm);
    overflow: hidden;
    transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
}
.feature::before {
    content: "";
    position: absolute;
    inset: 0;
    border-radius: inherit;
    padding: 1px;
    background: var(--gradient-brand);
    -webkit-mask:
        linear-gradient(#000 0 0) content-box,
        linear-gradient(#000 0 0);
    -webkit-mask-composite: xor;
            mask-composite: exclude;
    opacity: 0;
    transition: opacity 0.25s ease;
    pointer-events: none;
}
.feature:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
}
.feature:hover::before { opacity: 1; }

.feature h3 { margin-top: 0; font-size: 1.125rem; }
.feature p { color: var(--color-muted); margin-bottom: 0; }

.about { background: var(--color-surface); }
.about p { color: var(--color-muted); max-width: 70ch; }

.site-footer {
    border-top: 1px solid var(--color-border);
    padding-block: var(--space-3);
    color: var(--color-muted);
    font-size: 0.9rem;
}
.site-footer .container {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-2);
    justify-content: space-between;
    align-items: center;
}

@media (min-width: 640px) {
    .features-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (min-width: 960px) {
    .features-grid { grid-template-columns: repeat(3, 1fr); }
}

@media (max-width: 720px) {
    .nav-toggle { display: inline-flex; }
    .site-nav {
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--color-bg);
        border-bottom: 1px solid var(--color-border);
        display: none;
    }
    .site-nav[data-open="true"] { display: block; }
    .site-nav ul {
        flex-direction: column;
        padding: var(--space-2);
        gap: var(--space-2);
    }
}

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