/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Arial', sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

/* Hamburger Menu Styles */
.hamburger-menu {
    position: fixed;
    top: 20px;
    left: 20px;
    width: 30px;
    height: 25px;
    cursor: pointer;
    z-index: 1001;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.hamburger-menu span {
    display: block;
    height: 3px;
    width: 100%;
    background: #fff;
    border-radius: 2px;
    transition: all 0.3s ease;
}

.hamburger-menu.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.hamburger-menu.active span:nth-child(2) {
    opacity: 0;
}

.hamburger-menu.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -6px);
}

/* Side Navigation */
.side-nav {
    position: fixed;
    top: 0;
    left: -250px;
    width: 250px;
    height: 100vh;
    background: #2c3e50;
    transition: left 0.3s ease;
    z-index: 1000;
    padding-top: 60px;
}

.side-nav.active {
    left: 0;
}

.side-nav ul {
    list-style: none;
}

.side-nav ul li {
    padding: 0;
}

.side-nav ul li a {
    display: block;
    padding: 15px 20px;
    color: #ecf0f1;
    text-decoration: none;
    transition: background 0.3s ease;
}

.side-nav ul li a:hover {
    background: #34495e;
}

/* Overlay */
.overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 999;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
}

.overlay.active {
    opacity: 1;
    visibility: visible;
}

/* Container */
.container {
    max-width: 600px;
    margin: 0 auto;
    padding: 20px;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* Registration Form */
.registration-form {
    background: white;
    padding: 40px;
    border-radius: 10px;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.1);
    width: 100%;
}

.registration-form h1 {
    text-align: center;
    margin-bottom: 30px;
    color: #2c3e50;
    font-size: 2.5em;
}

/* Form Groups */
.form-group {
    margin-bottom: 20px;
}

.form-group label,
.form-group legend {
    display: block;
    margin-bottom: 5px;
    font-weight: bold;
    color: #555;
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 12px;
    border: 2px solid #ddd;
    border-radius: 5px;
    font-size: 16px;
    transition: border-color 0.3s ease;
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.form-group input.valid {
    border-color: #27ae60;
}

.form-group input.invalid {
    border-color: #e74c3c;
}

/* Radio and Checkbox Groups */
.radio-group {
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
}

.radio-group input[type="radio"] {
    width: auto;
    margin-right: 5px;
}

.checkbox-group {
    display: flex;
    align-items: center;
    gap: 10px;
}

.checkbox-group input[type="checkbox"] {
    width: auto;
}

/* Password Strength Meter */
.password-strength-meter {
    margin-top: 10px;
}

.strength-bar {
    height: 5px;
    background: #ddd;
    border-radius: 3px;
    overflow: hidden;
    position: relative;
}

.strength-bar::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    height: 100%;
    width: 0%;
    transition: all 0.3s ease;
    border-radius: 3px;
}

.strength-bar.weak::before {
    width: 25%;
    background: #e74c3c;
}

.strength-bar.fair::before {
    width: 50%;
    background: #f39c12;
}

.strength-bar.good::before {
    width: 75%;
    background: #f1c40f;
}

.strength-bar.strong::before {
    width: 100%;
    background: #27ae60;
}

.strength-text {
    font-size: 12px;
    margin-top: 5px;
    color: #666;
}

/* Error Messages */
.error-message {
    color: #e74c3c;
    font-size: 14px;
    margin-top: 5px;
    min-height: 20px;
}

/* Submit Button */
.submit-btn {
    width: 100%;
    padding: 15px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 5px;
    font-size: 18px;
    font-weight: bold;
    cursor: pointer;
    transition: transform 0.2s ease;
}

.submit-btn:hover {
    transform: translateY(-2px);
}

.submit-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

/* Success Message */
.success-message {
    text-align: center;
    color: #27ae60;
}

.success-message h2 {
    margin-bottom: 10px;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 10px;
    }
    
    .registration-form {
        padding: 20px;
    }
    
    .registration-form h1 {
        font-size: 2em;
    }
    
    .radio-group {
        flex-direction: column;
        gap: 10px;
    }
}

/* Fieldset Styles */
fieldset {
    border: none;
    padding: 0;
}

legend {
    font-weight: bold;
    color: #555;
    margin-bottom: 10px;
}