* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Arial', sans-serif;
}

body {
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    background: linear-gradient(45deg,
        #e8e8e8,
        #d4d4d4 25%,
        #c0c0c0 50%,
        #d4d4d4 75%,
        #e8e8e8
    );
    position: relative;
    overflow: hidden;
}

/* Metallic texture overlay */
body::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: 
        linear-gradient(90deg, 
            rgba(255,255,255, 0.07) 0%,
            rgba(255,255,255, 0.13) 50%,
            rgba(255,255,255, 0.07) 100%
        );
    background-size: 50px 100%;
    pointer-events: none;
}

.calculator-container {
    padding: 20px;
    border-radius: 20px;
    backdrop-filter: blur(10px);
    background: rgba(0, 0, 0, 0.15);
    border: 1px solid rgba(255, 255, 255, 0.2);
    box-shadow: 0 25px 45px rgba(0, 0, 0, 0.2);
}

.calculator {
    background: rgba(30, 30, 30, 0.9);
    padding: 20px;
    border-radius: 15px;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.5);
    width: 320px;
}

.display {
    background: #2c3e50;
    padding: 20px;
    border-radius: 10px;
    margin-bottom: 20px;
    text-align: right;
    height: 100px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    box-shadow: inset 0 0 10px rgba(0, 0, 0, 0.5);
    overflow: hidden;
}

.previous-operand {
    color: rgba(255, 255, 255, 0.7);
    font-size: 1.2rem;
    height: 24px;
    font-family: 'Courier New', monospace;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.current-operand {
    color: white;
    font-size: 2.5rem;
    font-weight: 300;
    font-family: 'Courier New', monospace;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    height: 48px;
    line-height: 48px;
}

.buttons {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 10px;
}

button {
    padding: 15px;
    font-size: 1.4rem;
    border: none;
    border-radius: 10px;
    background: #34495e;
    color: white;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
}

button:hover {
    background: #2c3e50;
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.4);
}

button:active {
    transform: translateY(1px);
}

.operator {
    background: #e67e22;
}

.operator:hover {
    background: #d35400;
}

.special {
    background: #c0392b;
}

.special:hover {
    background: #a93226;
}

.equals {
    background: #27ae60;
    grid-column: span 2;
}

.equals:hover {
    background: #219a52;
}

/* Glowing effect on buttons */
button::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border-radius: 10px;
    opacity: 0;
    transition: opacity 0.3s ease;
    box-shadow: 0 0 15px rgba(255, 255, 255, 0.3);
    pointer-events: none;
}

button:hover::after {
    opacity: 1;
}