:root {
    --primary: #0051ff;
    --primary-hover: #003db3;
    --bg: #f4f7f6;
    --card-bg: #ffffff;
    --text: #333;
    --text-light: #666;
    --border: #ddd;
    --radius: 8px;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

* {
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg);
    color: var(--text);
    line-height: 1.6;
    margin: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
}

.container {
    width: 100%;
    max-width: 500px;
    padding: 20px;
    background: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

header {
    text-align: center;
    margin-bottom: 30px;
}

header h1 {
    margin: 0;
    font-size: 1.5rem;
    color: var(--primary);
}

header p {
    color: var(--text-light);
    font-size: 0.9rem;
}

.form-group {
    margin-bottom: 20px;
}

label {
    display: block;
    margin-bottom: 5px;
    font-weight: 600;
    font-size: 0.9rem;
}

input[type="text"],
input[type="password"],
input[type="file"] {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    font-size: 1rem;
}

.hint {
    font-size: 0.8rem;
    color: var(--text-light);
    margin-top: 5px;
}

button {
    width: 100%;
    padding: 12px;
    background-color: var(--primary);
    color: white;
    border: none;
    border-radius: var(--radius);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s;
}

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

button:disabled {
    background-color: #ccc;
    cursor: not-allowed;
}

.status-box {
    margin-top: 20px;
    padding: 10px;
    border-radius: var(--radius);
    font-size: 0.9rem;
    text-align: center;
}

.status-box.error {
    background-color: #ffebee;
    color: #c62828;
    border: 1px solid #ffcdd2;
}

.status-box.success {
    background-color: #e8f5e9;
    color: #2e7d32;
    border: 1px solid #c8e6c9;
}

#preview-section {
    margin-top: 30px;
    padding-top: 20px;
    border-top: 1px solid var(--border);
    text-align: center;
}

#canvas {
    image-rendering: pixelated;
    border: 1px solid var(--border);
    margin: 10px 0;
}

.hidden {
    display: none;
}

#download-link {
    display: inline-block;
    margin-top: 10px;
    padding: 8px 16px;
    background-color: #444;
    color: white;
    text-decoration: none;
    border-radius: var(--radius);
    font-size: 0.9rem;
}

#download-link:hover {
    background-color: #222;
}