:root {
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-dark: #000000;
    --text-primary: #000000;
    --text-secondary: #6c757d;
    --border-color: #dee2e6;
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    padding: 0;
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

#app {
    min-height: 100vh;
    padding: 20px 0;
}

.screen {
    animation: fadeIn 0.3s ease-in;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.container {
    max-width: 600px;
    margin: 0 auto;
    padding: 0 15px;
}

.card {
    background-color: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.card-header {
    background-color: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    padding: 16px 20px;
    border-radius: 12px 12px 0 0;
}

.card-body {
    padding: 20px;
}

.form-control {
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 12px 16px;
    font-size: 16px;
}

.form-control:focus {
    border-color: var(--bg-dark);
    box-shadow: 0 0 0 0.2rem rgba(0, 0, 0, 0.1);
}

.form-control:readonly {
    background-color: var(--bg-secondary);
}

.btn {
    border-radius: 8px;
    padding: 12px 24px;
    font-weight: 500;
    font-size: 16px;
    transition: all 0.2s ease;
}

.btn-dark {
    background-color: var(--bg-dark);
    border-color: var(--bg-dark);
    color: var(--bg-primary);
}

.btn-dark:hover {
    background-color: #333;
    border-color: #333;
}

.btn-outline-secondary {
    color: var(--text-secondary);
    border-color: var(--border-color);
}

.btn-outline-secondary:hover {
    background-color: var(--bg-secondary);
    border-color: var(--border-color);
    color: var(--text-primary);
}

.alert {
    border-radius: 8px;
    padding: 12px 16px;
    margin-bottom: 16px;
}

.alert-danger {
    background-color: #fff5f5;
    color: #c53030;
    border: 1px solid #feb2b2;
}

.alert-success {
    background-color: #f0fff4;
    color: #22543d;
    border: 1px solid #9ae6b4;
}

#loadingOverlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
}

.text-muted {
    color: var(--text-secondary) !important;
}

.d-none {
    display: none !important;
}