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

body, html {
    width: 100%;
    height: 100%;
    overflow: hidden;
    background-color: #000;
    font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
}

canvas {
    display: block;
    position: absolute;
    top: 0;
    left: 0;
    z-index: 1;
}

#overlay {
    position: absolute;
    bottom: 10%;
    width: 100%;
    text-align: center;
    z-index: 2;
    pointer-events: none;
}

#text-container {
    color: rgba(255, 255, 255, 0.9);
    font-size: 24px;
    font-weight: 300;
    letter-spacing: 2px;
    text-shadow: 0 0 10px rgba(255, 255, 255, 0.5);
    transition: opacity 1s ease-in-out;
    opacity: 0;
}

#text-container.visible {
    opacity: 1;
}

#start-screen {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at center, #1a1a2e 0%, #000000 100%);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 10;
    transition: opacity 0.8s ease-out;
}

.start-content {
    text-align: center;
    color: #fff;
    animation: fadeIn 1.5s ease-out;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.main-title {
    font-size: 4rem;
    font-weight: 200;
    letter-spacing: 0.5rem;
    margin-bottom: 1rem;
    background: linear-gradient(120deg, #fff, #a5b4fc, #fff);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    text-shadow: 0 0 30px rgba(165, 180, 252, 0.3);
}

.sub-title {
    font-size: 1.2rem;
    font-weight: 300;
    letter-spacing: 0.8rem;
    margin-bottom: 3rem;
    color: rgba(255, 255, 255, 0.7);
    text-transform: uppercase;
}

#start-btn {
    position: relative;
    padding: 18px 50px;
    font-size: 1.2rem;
    background: rgba(255, 255, 255, 0.05);
    color: #fff;
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 50px;
    cursor: pointer;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    backdrop-filter: blur(10px);
    overflow: hidden;
    letter-spacing: 4px;
    font-weight: 300;
}

.btn-text {
    position: relative;
    z-index: 2;
}

.btn-glow {
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: 0.5s;
    z-index: 1;
}

#start-btn:hover {
    border-color: rgba(255, 255, 255, 0.8);
    box-shadow: 0 0 30px rgba(255, 255, 255, 0.2);
    transform: scale(1.05);
    letter-spacing: 6px;
}

#start-btn:hover .btn-glow {
    left: 100%;
    transition: 0.5s;
}

#start-screen.hidden {
    opacity: 0;
    pointer-events: none;
    transform: scale(1.1);
}