:root {
    --primary-color: #007BFF;
    --primary-hover-color: #0056b3;
    --secondary-color: #f8f9fa;
    --text-color: #333;
    --border-color: #dee2e6;
    --success-color: #28a745;
    --error-color: #dc3545;
    --background-color: #e9ecef;
    --container-bg: #fff;
}

body {
    font-family: 'Roboto', sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    margin: 0;
    padding: 20px;
    display: flex;
    justify-content: center;
    align-items: flex-start;
    min-height: 100vh;
}

.container {
    width: 100%;
    max-width: 800px;
    background-color: var(--container-bg);
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    overflow: hidden;
}

header {
    background-color: var(--primary-color);
    color: white;
    padding: 20px 30px;
    text-align: center;
}

header h1 {
    margin: 0;
    font-weight: 700;
}

header p {
    margin: 5px 0 0;
    font-weight: 300;
    opacity: 0.9;
}

main {
    padding: 30px;
}

.input-section {
    margin-bottom: 25px;
}

.input-section label {
    display: block;
    font-weight: 700;
    margin-bottom: 8px;
}

#proxy-url {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-size: 16px;
    box-sizing: border-box;
    margin-bottom: 15px;
}

#start-btn {
    width: 100%;
    padding: 12px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 4px;
    font-size: 16px;
    font-weight: 700;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

#start-btn:hover {
    background-color: var(--primary-hover-color);
}

#start-btn:disabled {
    background-color: #a0a0a0;
    cursor: not-allowed;
}

.error-message {
    background-color: var(--error-color);
    color: white;
    padding: 15px;
    border-radius: 4px;
    margin-bottom: 20px;
    text-align: center;
}

.progress-section, .result-section {
    background-color: var(--secondary-color);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 20px;
    margin-top: 20px;
}

h2 {
    text-align: center;
    margin-top: 0;
    color: var(--primary-color);
}

.progress-bar-container {
    width: 100%;
    background-color: #e9ecef;
    border-radius: 25px;
    overflow: hidden;
    margin-bottom: 20px;
}

.progress-bar {
    width: 0%;
    height: 20px;
    background-color: var(--success-color);
    border-radius: 25px;
    text-align: center;
    color: white;
    line-height: 20px;
    font-weight: bold;
    transition: width 0.4s ease;
}

.stats p {
    margin: 8px 0;
    font-size: 16px;
}

.stats span {
    font-weight: 700;
}

.result-section {
    text-align: center;
}

.download-btn {
    display: inline-block;
    padding: 12px 25px;
    background-color: var(--success-color);
    color: white;
    text-decoration: none;
    border-radius: 4px;
    font-size: 16px;
    font-weight: 700;
    margin-top: 10px;
    transition: background-color 0.3s ease;
}

.download-btn:hover {
    background-color: #218838;
}

footer {
    background-color: #f1f1f1;
    color: #666;
    text-align: center;
    padding: 15px;
    font-size: 14px;
    border-top: 1px solid var(--border-color);
}