:root {
    --primary-color: #4361ee;
    --secondary-color: #3f37c9;
    --accent-color: #4895ef;
    --light-color: #f8f9fa;
    --dark-color: #212529;
    --success-color: #4bb543;
    --warning-color: #f0ad4e;
    --danger-color: #d9534f;
    --gray-color: #6c757d;
    --border-radius: 8px;
    --box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background-color: #f5f7fb;
    color: var(--dark-color);
    line-height: 1.6;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 2rem;
}

header {
    text-align: center;
    margin-bottom: 2rem;
}

header h1 {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

header h1 i {
    margin-right: 0.5rem;
}

header p {
    color: var(--gray-color);
    font-size: 1.1rem;
}

.upload-area {
    background-color: white;
    border: 2px dashed var(--gray-color);
    border-radius: var(--border-radius);
    padding: 3rem 2rem;
    text-align: center;
    cursor: pointer;
    margin-bottom: 2rem;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.upload-area:hover {
    border-color: var(--primary-color);
}

.upload-area i {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.upload-area h2 {
    margin-bottom: 0.5rem;
    color: var(--dark-color);
}

.upload-area p {
    color: var(--gray-color);
    margin-bottom: 1.5rem;
}

.upload-area input[type="file"] {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    opacity: 0;
    cursor: pointer;
}

.progress-container {
    width: 100%;
    height: 8px;
    background-color: #e9ecef;
    border-radius: 4px;
    margin-top: 1rem;
    display: none;
}

.progress-bar {
    height: 100%;
    width: 0%;
    background-color: var(--primary-color);
    border-radius: 4px;
    transition: width 0.3s ease;
}

.settings-panel, .result-panel {
    background-color: white;
    border-radius: var(--border-radius);
    padding: 2rem;
    margin-bottom: 2rem;
    box-shadow: var(--box-shadow);
    display: none;
}

.settings-panel h2, .result-panel h2 {
    margin-bottom: 1.5rem;
    color: var(--dark-color);
    display: flex;
    align-items: center;
}

.settings-panel h2 i, .result-panel h2 i {
    margin-right: 0.5rem;
    color: var(--primary-color);
}

.result-panel h2 i {
    color: var(--success-color);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--dark-color);
}

.form-group input, .form-group select {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid #ced4da;
    border-radius: var(--border-radius);
    font-size: 1rem;
    transition: var(--transition);
}

.form-group input:focus, .form-group select:focus {
    border-color: var(--primary-color);
    outline: none;
    box-shadow: 0 0 0 3px rgba(67, 97, 238, 0.2);
}

.password-strength {
    height: 4px;
    background-color: #e9ecef;
    border-radius: 2px;
    margin-top: 0.5rem;
    overflow: hidden;
}

.password-strength::after {
    content: '';
    display: block;
    height: 100%;
    width: 0%;
    transition: width 0.3s ease;
}

.btn-primary, .btn-secondary {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: var(--border-radius);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    width: 100%;
    margin-top: 0.5rem;
}

.btn-primary {
    background-color: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background-color: var(--secondary-color);
    transform: translateY(-2px);
}

.btn-primary:disabled {
    background-color: var(--gray-color);
    cursor: not-allowed;
    transform: none;
}

.btn-primary i, .btn-secondary i {
    margin-right: 0.5rem;
}

.btn-secondary {
    background-color: white;
    color: var(--primary-color);
    border: 1px solid var(--primary-color);
}

.btn-secondary:hover {
    background-color: #f0f5ff;
}

footer {
    text-align: center;
    color: var(--gray-color);
    font-size: 0.9rem;
    margin-top: 2rem;
}

/* Responsive design */
@media (max-width: 768px) {
    .container {
        padding: 1rem;
    }
    
    header h1 {
        font-size: 2rem;
    }
    
    .upload-area {
        padding: 2rem 1rem;
    }
}

/* Password strength indicators */
.strength-0::after {
    width: 20%;
    background-color: var(--danger-color);
}

.strength-1::after {
    width: 40%;
    background-color: #ff6b35;
}

.strength-2::after {
    width: 60%;
    background-color: var(--warning-color);
}

.strength-3::after {
    width: 80%;
    background-color: #8ac926;
}

.strength-4::after {
    width: 100%;
    background-color: var(--success-color);
}