:root {
    --bg: #0f1623;
    --text: #f4f8ff;
    --accent: #3b82f6;
    --accent-hover: #2563eb;
    --hero-offset-y: -10vh;
}

* {
    box-sizing: border-box;
}

html,
body {
    width: 100%;
    height: 100%;
}

body {
    margin: 0;
    overflow: hidden;
    position: relative;
    font-family: "Segoe UI", "Helvetica Neue", Arial, sans-serif;
    color: var(--text);
    background:
        radial-gradient(circle at 20% 20%, rgba(59, 130, 246, 0.22), transparent 40%),
        radial-gradient(circle at 80% 80%, rgba(14, 165, 233, 0.2), transparent 36%),
        var(--bg);
}

#particles-js canvas {
    position: fixed;
    inset: 0;
    z-index: 0;
}

.access-btn {
    position: fixed;
    top: 18px;
    right: 18px;
    z-index: 2;
    text-decoration: none;
    color: #ffffff;
    background: #2563eb;
    border: 1px solid rgba(255, 255, 255, 0.14);
    border-radius: 10px;
    padding: 10px 18px;
    font-weight: 600;
    letter-spacing: 0.01em;
    transition: background-color 0.2s ease, border-color 0.2s ease;
}

.access-btn:hover {
    background: #1f56cc;
    border-color: rgba(255, 255, 255, 0.2);
}

.access-btn:active {
    background: #1c4db8;
}

.hero-stage {
    position: relative;
    z-index: 1;
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.hero-title {
    margin: 0;
    font-size: clamp(3.2rem, 13vw, 10rem);
    font-weight: 800;
    letter-spacing: 0.16em;
    color: var(--text);
    text-shadow: 0 16px 40px rgba(0, 0, 0, 0.45);
    transform: translateY(var(--hero-offset-y));
    user-select: none;
}

@media (max-width: 640px) {
    .access-btn {
        top: 14px;
        right: 14px;
        padding: 9px 14px;
        font-size: 0.9rem;
    }

    .hero-title {
        letter-spacing: 0.12em;
    }
}