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

body {
    width: 100%;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    background: linear-gradient(135deg, #0f2027, #203a43, #2c5364);
    /* deep teal gradient */
}

.calculator {
    background-color: #1e2a30;
    width: 340px;
    padding: 20px;
    border-radius: 12px;
    border: none;
    box-shadow: 0px 8px 25px rgba(0, 0, 0, 0.7);
}

.calculator h2 {
    margin-bottom: 20px;
    font-size: 24px;
    font-weight: bold;
    color: #ff7043;
    text-align: center;
    text-shadow: 0px 0px 6px rgba(255, 112, 67, 0.4);
}

.calculator form input {
    width: 100%;
    height: 60px;
    margin: 10px 0;
    border: none;
    outline: none;
    border-radius: 8px;
    font-size: 22px;
    text-align: right;
    padding: 0 15px;
    background: #2c3e50;
    color: #fff;
    box-shadow: inset 0 2px 6px rgba(0, 0, 0, 0.5);
    cursor: default;
}

.buttons {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 10px;
    justify-items: center;
}

.calculator button {
    width: 100%;
    height: 60px;
    font-size: 18px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: 0.2s ease;
}


.calculator .number {
    background: #37474f;
    color: #fff;
}

.calculator .number:hover {
    background: #455a64;
}


.calculator .operator {
    background: #ff7043;
    color: #fff;
    font-weight: bold;
}

.calculator .operator:hover {
    background: #e65c2e;
}


.calculator .clear {
    background: #42a5f5;
    color: #fff;
}

.calculator .clear:hover {
    background: #1e88e5;
}


.calculator .allclear {
    background: #e53935;
    color: #fff;
}

.calculator .allclear:hover {
    background: #c62828;
}


.calculator .Equal {
    background: #00e676;
    color: #000;
    font-weight: bold;
}

.calculator .Equal:hover {
    background: #00c853;
}

.calculator .operation {
    background: #37474f;
    color: #fff;
    font-weight: bold;
}

.calculator .operation:hover {
    background: #e65c2e;
}

.calculator .bracket {
    background: #ff7043;
    color: #fff;
    font-weight: bold;
}

.calculator .bracket:hover {
    background: #e65c2e;
}

@media (max-width: 480px) {
    body {
        padding: 5px;
    }

    .calculator {
        width: 95%;
        padding: 15px;
    }

    .calculator h2 {
        font-size: 1.3rem;
        margin-bottom: 15px;
    }

    .calculator form input {
        height: 45px;
        font-size: 18px;
        padding: 0 10px;
    }

    .calculator button {
        height: 50px;
        font-size: 16px;
    }

    .buttons {
        gap: 5px;
    }
}