/* Reset */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

/* Background */
.background {
    background: linear-gradient(to right, #fbc2eb, #a6c1ee);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

/* Calculator Card */
.calculator-card {
    background: white;
    padding: 30px 25px;
    border-radius: 15px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.2);
    width: 100%;
    max-width: 400px;
    text-align: center;
    animation: fadeIn 1s ease;
}

.calculator-card h1 {
    margin-bottom: 10px;
}

.subtitle {
    font-size: 14px;
    color: #666;
    margin-bottom: 20px;
}

/* Input Groups */
.input-group {
    text-align: left;
    margin-bottom: 15px;
}

.input-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
}

.input-group input,
.input-group select {
    width: 100%;
    padding: 10px;
    border-radius: 8px;
    border: 1px solid #ccc;
    transition: 0.3s;
}

.input-group input:focus,
.input-group select:focus {
    border-color: #6a11cb;
    box-shadow: 0 0 5px rgba(106, 17, 203, 0.5);
    outline: none;
}

/* Button */
button {
    background: #6a11cb;
    color: white;
    border: none;
    padding: 12px;
    border-radius: 8px;
    cursor: pointer;
    width: 100%;
    font-size: 16px;
    transition: 0.3s;
    margin-top: 10px;
}

button:hover {
    background: #2575fc;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    z-index: 100;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background: rgba(0,0,0,0.5);
}

.modal-content {
    background: white;
    margin: 15% auto;
    padding: 20px;
    border-radius: 15px;
    width: 90%;
    max-width: 400px;
    text-align: center;
    position: relative;
}

.close {
    color: #aaa;
    position: absolute;
    top: 10px;
    right: 15px;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
}

.close:hover {
    color: black;
}

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