* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "Segoe UI", sans-serif;
}

body {
    height: 100vh;
    background: #000;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow: hidden;
    animation: neonBG 10s infinite alternate;
}

/* MULTI COLOR NEON BACKGROUND */
@keyframes neonBG {
    0% { box-shadow: inset 0 0 120px #ff4ecd; }
    20% { box-shadow: inset 0 0 120px #00ff9d; }
    40% { box-shadow: inset 0 0 120px #ffee00; }
    60% { box-shadow: inset 0 0 120px #9b5cff; }
    80% { box-shadow: inset 0 0 120px #ff4444; }
    100% { box-shadow: inset 0 0 120px #00bfff; }
}

/* FLOATING CURRENCY SYMBOLS */
.background span {
    position: absolute;
    font-size: 3rem;
    opacity: 0.15;
    animation: float 10s infinite linear;
}

.background span:nth-child(1){ left:10%; }
.background span:nth-child(2){ left:30%; animation-delay:2s;}
.background span:nth-child(3){ left:60%; animation-delay:4s;}
.background span:nth-child(4){ left:80%; animation-delay:6s;}

@keyframes float {
    from { bottom: -10%; }
    to { bottom: 110%; }
}

/* CARD */
.converter {
    width: 360px;
    padding: 30px;
    border-radius: 16px;
    text-align: center;
    color: white;
    background: rgba(255,255,255,0.1);
    backdrop-filter: blur(18px);
    animation: neonBorder 6s infinite alternate;
}

@keyframes neonBorder {
    0% { box-shadow: 0 0 25px #ff4ecd; }
    50% { box-shadow: 0 0 25px #00ff9d; }
    100% { box-shadow: 0 0 25px #9b5cff; }
}

input {
    width: 100%;
    padding: 12px;
    margin: 15px 0;
    border-radius: 8px;
    border: none;
    outline: none;
}

.row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin: 15px 0;
}

.select-box {
    display: flex;
    align-items: center;
    background: white;
    border-radius: 8px;
    padding: 6px;
    gap: 6px;
}

.select-box img {
    width: 28px;
}

select {
    border: none;
    outline: none;
}

/* SWAP BUTTON */
.swap-btn {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: linear-gradient(45deg,#ff4ecd,#00ffd5);
    color: black;
    font-size: 18px;
    cursor: pointer;
    border: none;
    transition: transform 0.4s ease;
}

.swap-btn.rotate {
    transform: rotate(180deg);
}

/* WET BUTTON */
.convert-btn {
    width: 100%;
    padding: 14px;
    margin-top: 10px;
    font-size: 1rem;
    border-radius: 12px;
    border: none;
    cursor: pointer;
    background: linear-gradient(45deg,#00ffd5,#0099ff);
    box-shadow: 0 0 15px #00ffd5;
    position: relative;
    overflow: hidden;
}

.convert-btn:active {
    transform: scale(0.95);
}

.convert-btn::after {
    content: "";
    position: absolute;
    width: 300%;
    height: 300%;
    background: rgba(255,255,255,0.3);
    top: -100%;
    left: -100%;
    border-radius: 50%;
    opacity: 0;
}

.convert-btn:active::after {
    opacity: 1;
    animation: ripple 0.6s linear;
}

@keyframes ripple {
    to {
        transform: scale(1.4);
        opacity: 0;
    }
}

#result {
    margin-top: 15px;
    color: #00ffd5;
}