:root {
    --font-family: Arial, sans-serif;
    --bg-main: #f4f4f9;
    --bg-container: #fff;
    --bg-log: #eef2f3;
    --text-main: #333;
    --text-subtitle: #666;
    --text-log: #444;
    --color-primary: #202020;
    --color-primary-hover: #525252;
    --border-color: #ccc;
    --radius: 8px;
    --radius-sm: 4px;
    --shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
    --spacing: 20px;
}

body {
    font-family: var(--font-family);
    background-color: var(--bg-main);
    color: var(--text-main);
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
}

.container {
    width: 100%;
    max-width: 500px;
    background: var(--bg-container);
    padding: 30px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    box-sizing: border-box;
}

h1 { 
    color: var(--color-primary); 
    text-align: center; 
    margin-bottom: 5px;
}

.subtitle {
    text-align: center;
    color: var(--text-subtitle);
    font-size: 14px;
    margin-bottom: 25px;
}

.form-group { 
    margin-bottom: var(--spacing); 
}

label { 
    display: block; 
    margin-bottom: 8px; 
    font-weight: bold; 
    font-size: 14px;
}

input[type="text"] {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    box-sizing: border-box;
    font-size: 14px;
}

button {
    background-color: var(--color-primary);
    color: white;
    padding: 12px;
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    width: 100%;
    font-size: 16px;
    font-weight: bold;
}

button:hover { 
    background-color: var(--color-primary-hover); 
}

#log {
    margin-top: var(--spacing);
    padding: 12px;
    background: var(--bg-log);
    border-radius: var(--radius-sm);
    max-height: 120px;
    overflow-y: auto;
    font-family: monospace;
    font-size: 13px;
    color: var(--text-log);
}

.footer {
    position: fixed;
    bottom: 0;
    left: 0;
    width: 100%;
    background-color: var(--bg-main);
    color: var(--text-main);
    font-family: var(--font-family);
    text-align: center;
    padding: 10px 0;
    font-size: 13px;
    box-sizing: border-box;
}

.footer a {
    color: var(--color-primary);
    text-decoration: none;
    font-weight: bold;
}

.footer a:hover {
    text-decoration: underline;
}