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

body {
    font-family: 'Malgun Gothic', sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.container {
    background: white;
    border-radius: 20px;
    padding: 40px;
    max-width: 800px;
    width: 100%;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
}

h1 {
    color: #667eea;
    text-align: center;
    margin-bottom: 10px;
    font-size: 2em;
}

.subtitle {
    text-align: center;
    color: #666;
    margin-bottom: 30px;
    font-size: 0.95em;
}

.screen {
    display: none;
}

.screen.active {
    display: block;
    animation: fadeIn 0.5s;
}

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

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

textarea {
    width: 100%;
    padding: 15px;
    border: 2px solid #e0e0e0;
    border-radius: 10px;
    font-size: 1em;
    font-family: inherit;
    resize: vertical;
    transition: border-color 0.3s;
}

textarea:focus {
    outline: none;
    border-color: #667eea;
}

button {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    padding: 15px 40px;
    border-radius: 30px;
    font-size: 1.1em;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
    margin-top: 20px;
    width: 100%;
}

button:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(102, 126, 234, 0.3);
}

button:active {
    transform: translateY(0);
}

button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

.error-message {
    background: #ffe0e0;
    color: #d32f2f;
    padding: 15px;
    border-radius: 10px;
    margin-bottom: 20px;
    text-align: center;
}

.section-title {
    color: #764ba2;
    font-size: 1.2em;
    margin-bottom: 15px;
    padding-bottom: 10px;
    border-bottom: 2px solid #e0e0e0;
}

@media (max-width: 600px) {
    .container {
        padding: 25px;
    }

    h1 {
        font-size: 1.5em;
    }

    button {
        padding: 12px 30px;
        font-size: 1em;
    }
}