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

body {
    background: radial-gradient(circle at center, #1a0033 0%, #000000 100%);
    overflow: hidden;
    font-family: 'Teko', sans-serif;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

#khungkhonggian3d {
    position: absolute;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: 1;
    pointer-events: none;
}

.vungtrungtam {
    position: relative;
    z-index: 10;
    display: flex;
    justify-content: center;
    align-items: center;
    width: 80%;
    max-width: 1200px;
}

.hieuungkinh {
    background: rgba(20, 0, 30, 0.6);
    backdrop-filter: blur(15px);
    -webkit-backdrop-filter: blur(15px);
    border: 2px solid rgba(255, 215, 0, 0.3);
    border-radius: 20px;
    padding: 4rem 2rem;
    width: 100%;
    text-align: center;
    box-shadow: 0 0 40px rgba(255, 215, 0, 0.2), inset 0 0 20px rgba(255, 215, 0, 0.1);
    animation: nhipdapkinh 2s infinite alternate;
}

.chudao {
    color: #00e5ff;
    font-size: 2.5rem;
    letter-spacing: 4px;
    text-transform: uppercase;
    text-shadow: 0 0 10px #00e5ff, 0 0 20px #00e5ff;
    margin-bottom: 20px;
}

#chugiua {
    font-size: 5rem;
    color: #ffd700;
    text-transform: uppercase;
    outline: none;
    border: none;
    background: transparent;
    text-shadow: 0 0 20px #ffd700, 0 0 40px #ff8c00, 0 0 80px #ff0000;
    cursor: text;
    transition: all 0.3s ease;
}

#chugiua:focus {
    text-shadow: 0 0 30px #ffffff, 0 0 60px #ffd700, 0 0 100px #ff8c00;
    transform: scale(1.02);
}

.denchopden {
    position: absolute;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(255, 0, 200, 0.05);
    z-index: 5;
    pointer-events: none;
    mix-blend-mode: overlay;
    animation: chopdenbar 0.5s infinite;
}

.banquyen {
    position: absolute;
    bottom: 20px;
    width: 100%;
    text-align: center;
    color: rgba(255, 215, 0, 0.5);
    font-size: 1.2rem;
    z-index: 20;
    letter-spacing: 2px;
}

@keyframes nhipdapkinh {
    0% { box-shadow: 0 0 40px rgba(255, 215, 0, 0.1), inset 0 0 20px rgba(255, 215, 0, 0.1); border-color: rgba(255, 215, 0, 0.2); }
    100% { box-shadow: 0 0 60px rgba(255, 215, 0, 0.4), inset 0 0 40px rgba(255, 215, 0, 0.2); border-color: rgba(255, 215, 0, 0.6); }
}

@keyframes chopdenbar {
    0%, 100% { opacity: 0; }
    50% { opacity: 0.1; background: rgba(0, 229, 255, 0.1); }
    75% { opacity: 0.15; background: rgba(255, 215, 0, 0.1); }
}