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

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

.container {
    background: white;
    padding: 40px;
    border-radius: 20px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
    max-width: 500px;
    width: 100%;
}

h1 {
    text-align: center;
    color: #333;
    margin-bottom: 30px;
    font-size: 2.5em;
}

.password-box {
    display: flex;
    gap: 10px;
    margin-bottom: 30px;
}

#password {
    flex: 1;
    padding: 15px;
    border: 2px solid #e0e0e0;
    border-radius: 10px;
    font-size: 16px;
    font-family: 'Courier New', monospace;
    background: #f8f9fa;
    color: #333;
}

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

.copy-btn {
    padding: 15px 20px;
    background: #28a745;
    color: white;
    border: none;
    border-radius: 10px;
    cursor: pointer;
    font-size: 16px;
    transition: all 0.3s ease;
}

.copy-btn:hover {
    background: #218838;
    transform: translateY(-2px);
}

.options {
    margin-bottom: 30px;
}

.option {
    margin-bottom: 15px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.option label {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 16px;
    color: #555;
    cursor: pointer;
}

.option input[type="range"] {
    flex: 1;
    height: 6px;
    border-radius: 3px;
    background: #e0e0e0;
    outline: none;
    -webkit-appearance: none;
}

.option input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: #667eea;
    cursor: pointer;
}

.option input[type="checkbox"] {
    width: 18px;
    height: 18px;
    accent-color: #667eea;
}

#lengthValue {
    font-weight: bold;
    color: #667eea;
    min-width: 30px;
}

.generate-btn {
    width: 100%;
    padding: 15px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 10px;
    font-size: 18px;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
    margin-bottom: 20px;
}

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

.strength-meter {
    text-align: center;
}

.strength-bar {
    width: 100%;
    height: 8px;
    background: #e0e0e0;
    border-radius: 4px;
    overflow: hidden;
    margin-bottom: 10px;
}

.strength-fill {
    height: 100%;
    width: 0%;
    transition: all 0.3s ease;
    border-radius: 4px;
}

.strength-fill.weak {
    background: #dc3545;
    width: 25%;
}

.strength-fill.medium {
    background: #ffc107;
    width: 50%;
}

.strength-fill.strong {
    background: #28a745;
    width: 75%;
}

.strength-fill.very-strong {
    background: #20c997;
    width: 100%;
}

#strengthText {
    font-size: 14px;
    color: #666;
    font-weight: 500;
}

@media (max-width: 480px) {
    .container {
        padding: 20px;
    }
    
    h1 {
        font-size: 2em;
    }
    
    .password-box {
        flex-direction: column;
    }
    
    .copy-btn {
        width: 100%;
    }
}