body {
    margin: 0;
    font-family: Arial, sans-serif;
    background: #f5f7fa;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
}

#app {
    text-align: center;
}

.state {
    display: none;
}

.state.active {
    display: block;
}

/* Spinner */
.spinner {
    width: 60px;
    height: 60px;
    border: 6px solid #ddd;
    border-top-color: #2b3c55;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 20px auto;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Animated checkmark */
.checkmark {
    font-size: 90px;
    color: #28a745;
    transform: scale(0);
    animation: popIn 0.5s ease forwards;
}

@keyframes popIn {
    0% { transform: scale(0); }
    60% { transform: scale(1.2); }
    80% { transform: scale(0.95); }
    100% { transform: scale(1); }
}

/* Error */
.error-icon {
    font-size: 80px;
    color: #dc3545;
    margin-bottom: 10px;
}

/* Button */
button {
    margin-top: 15px;
    padding: 10px 20px;
    background: #2b3c55;
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 16px;
}

button:hover {
    background: #1e2937 ;
}

h1 { margin: 10px 0; }
h2 { color: #555; }
p { color: #777; }