.number-system-wrapper {
    display: flex;
    justify-content: center;
    margin: 40px 0;
}

.number-card {
    width: 380px;
    padding: 30px;
    border-radius: 20px;
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: #fff;
    box-shadow: 0 15px 35px rgba(0,0,0,0.25);
}

.number-card h1 {
    text-align: center;
    margin-bottom: 20px;
}

.number-card label {
    display: block;
    margin: 10px 0 6px;
}

.number-card input,
.number-card select {
    width: 100%;
    padding: 12px;
    border-radius: 10px;
    border: none;
    font-size: 16px;
    margin-bottom: 12px;
}

.results {
    margin-top: 15px;
    background: rgba(0,0,0,0.25);
    padding: 15px;
    border-radius: 15px;
}

.result-row {
    display: flex;
    justify-content: space-between;
    padding: 6px 0;
    border-bottom: 1px solid rgba(255,255,255,0.2);
}

.result-row:last-child {
    border-bottom: none;
}

.error {
    margin-top: 10px;
    text-align: center;
    color: #ffd1d1;
}