:root {
    --primary-color: #4e54c8;
    --secondary-color: #8f94fb;
}

body {
    background: linear-gradient(45deg, var(--primary-color), var(--secondary-color));
    min-height: 100vh;
    display: flex;
    align-items: center;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

.container {
    background-color: rgba(255, 255, 255, 0.95);
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
    backdrop-filter: blur(10px);
    max-width: 800px;
    width: 95%;
    margin: 2rem auto;
}

.form-control, .input-group-text {
    border-radius: 8px;
    padding: 0.7rem;
}

.form-control:focus {
    box-shadow: 0 0 0 0.25rem rgba(78, 84, 200, 0.25);
    border-color: var(--primary-color);
}

.btn-primary {
    background: linear-gradient(45deg, var(--primary-color), var(--secondary-color));
    border: none;
    padding: 0.8rem;
    border-radius: 8px;
    font-weight: 600;
    transition: transform 0.2s;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

.btn-success {
    padding: 0.8rem;
    border-radius: 8px;
    font-weight: 600;
}

h1 {
    color: var(--primary-color);
    font-weight: 700;
    margin-bottom: 2rem;
    text-align: center;
    font-size: 2.5rem;
}

.form-group {
    margin-bottom: 1.5rem;
}

label {
    margin-bottom: 0.5rem;
    color: #333;
    font-weight: 600;
}

#resultado, #passoAPasso {
    background-color: #f8f9fa;
}

@media (max-width: 768px) {
    .container {
        padding: 1.5rem;
        margin: 1rem auto;
    }

    h1 {
        font-size: 2rem;
    }
}

.loading-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 9999;
    justify-content: center;
    align-items: center;
}

.loading-spinner {
    width: 50px;
    height: 50px;
    border: 5px solid #f3f3f3;
    border-top: 5px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}