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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #012ffc 0%, #ff0000 100%);
    min-height: 102vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 22px;
}

.calculator {
    background: white;
    border-radius: 35px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.1);
    padding: 40px;
    max-width: 500px;
    width: 100%;
}

h1 {
    color: #333;
    text-align: center;
    margin-bottom: 30px;
    font-size: 28px;
    font-weight: 600;
}

.form-group {
    margin-bottom: 25px;
}

label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: #555;
    font-size: 14px;
}

input, select {
    width: 100%;
    padding: 12px 15px;
    border: 2px solid #e1e5e9;
    border-radius: 8px;
    font-size: 16px;
    transition: all 0.3s ease;
}

input:focus, select:focus {
    outline: none;
    border-color: #012ffc;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.range-container {
    display: flex;
    align-items: center;
    gap: 15px;
}

.range-container input[type="range"] {
    flex: 1;
}

.range-value {
    min-width: 40px;
    text-align: center;
    font-weight: 600;
    color: #012ffc;
}

.result {
    background: linear-gradient(135deg, #012ffc 0%, #ff0000 100%);
    color: white;
    padding: 30px;
    border-radius: 10px;
    text-align: center;
    margin-top: 20px;
}

.result-number {
    font-size: 48px;
    font-weight: 700;
    margin: 10px 0;
}

.result-label {
    font-size: 16px;
    opacity: 0.9;
}

.details {
    margin-top: 20px;
    padding: 20px;
    background: #f8f9fa;
    border-radius: 8px;
    font-size: 14px;
}

.detail-item {
    display: flex;
    justify-content: space-between;
    margin-bottom: 8px;
    padding-bottom: 8px;
    border-bottom: 1px solid #e9ecef;
}

.detail-item:last-child {
    margin-bottom: 0;
    border-bottom: none;
}

.preset-buttons {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
    margin-bottom: 20px;
}

.preset-btn {
    padding: 10px;
    border: 2px solid #012ffc;
    background: white;
    color: #012ffc;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 600;
}

.preset-btn:hover {
    background: #012ffc;
    color: white;
}

.preset-btn.active {
    background: #012ffc;
    color: white;
}