* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: "Segoe UI", system-ui, sans-serif;
    min-height: 100vh;
    background: linear-gradient(135deg, #0f172a, #1e1b4b);
    color: #f1f5f9;
    overflow-x: hidden;
}

.topbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 60;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1.4rem 2rem;
}

.brand {
    color: #fff;
    font-size: 1.5rem;
    font-weight: 800;
    letter-spacing: 1px;
    text-decoration: none;
}

.hamburger {
    position: relative;
    z-index: 80;
    width: 48px;
    height: 48px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 7px;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: 14px;
    cursor: pointer;
    backdrop-filter: blur(8px);
    transition: background 0.25s ease, transform 0.2s ease;
}

.hamburger:hover {
    background: rgba(255, 255, 255, 0.16);
    transform: scale(1.05);
}

.bar {
    width: 24px;
    height: 2.5px;
    border-radius: 3px;
    background: #fff;
    transition: transform 0.35s cubic-bezier(0.68, -0.55, 0.27, 1.55), opacity 0.25s ease, width 0.3s ease;
}

.hamburger.open .bar-1 {
    transform: translateY(9.5px) rotate(45deg);
}

.hamburger.open .bar-2 {
    opacity: 0;
    transform: translateX(-10px);
}

.hamburger.open .bar-3 {
    transform: translateY(-9.5px) rotate(-45deg);
}

.overlay {
    position: fixed;
    inset: 0;
    z-index: 50;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: radial-gradient(circle at 20% 30%, rgba(124, 58, 237, 0.35), transparent 45%),
        radial-gradient(circle at 80% 70%, rgba(14, 165, 233, 0.3), transparent 45%),
        #0b1026;
    clip-path: circle(0% at calc(100% - 3.2rem) 3.4rem);
    visibility: hidden;
    transition: clip-path 0.65s cubic-bezier(0.76, 0, 0.24, 1), visibility 0.65s;
}

.overlay.open {
    clip-path: circle(150% at calc(100% - 3.2rem) 3.4rem);
    visibility: visible;
}

.menu {
    list-style: none;
    text-align: center;
    display: flex;
    flex-direction: column;
    gap: 1.4rem;
}

.menu-item {
    opacity: 0;
    transform: translateY(26px);
}

.overlay.open .menu-item {
    opacity: 1;
    transform: translateY(0);
    transition: opacity 0.5s ease, transform 0.5s cubic-bezier(0.22, 1, 0.36, 1);
}

.overlay.open .menu-item:nth-child(1) {
    transition-delay: 0.15s;
}

.overlay.open .menu-item:nth-child(2) {
    transition-delay: 0.25s;
}

.overlay.open .menu-item:nth-child(3) {
    transition-delay: 0.35s;
}

.overlay.open .menu-item:nth-child(4) {
    transition-delay: 0.45s;
}

.overlay.open .menu-item:nth-child(5) {
    transition-delay: 0.55s;
}

.menu-link {
    position: relative;
    color: #e2e8f0;
    font-size: clamp(1.8rem, 5vw, 2.6rem);
    font-weight: 700;
    text-decoration: none;
    padding: 0.2rem 0.4rem;
    transition: color 0.25s ease;
}

.menu-link::after {
    content: "";
    position: absolute;
    left: 0;
    bottom: -2px;
    width: 100%;
    height: 3px;
    border-radius: 3px;
    background: linear-gradient(90deg, #8b5cf6, #06b6d4);
    transform: scaleX(0);
    transform-origin: right;
    transition: transform 0.35s ease;
}

.menu-link:hover {
    color: #fff;
}

.menu-link:hover::after {
    transform: scaleX(1);
    transform-origin: left;
}

.overlay-note {
    position: absolute;
    bottom: 2.2rem;
    color: #7c82a1;
    font-size: 0.85rem;
    letter-spacing: 4px;
    text-transform: uppercase;
    opacity: 0;
    transition: opacity 0.5s ease 0.6s;
}

.overlay.open .overlay-note {
    opacity: 1;
}

.hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 2rem;
    transition: filter 0.4s ease, transform 0.4s ease;
}

body.menu-open .hero {
    filter: blur(6px) brightness(0.6);
    transform: scale(0.98);
}

.hero h1 {
    font-size: clamp(2.2rem, 6vw, 4rem);
    font-weight: 800;
    line-height: 1.15;
}

.hero h1 span {
    background: linear-gradient(90deg, #a78bfa, #22d3ee);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

.hero p {
    margin-top: 1.2rem;
    color: #94a3b8;
    max-width: 420px;
    line-height: 1.7;
}