:root {
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #818cf8;
    --error-color: #ef4444;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --gradient-start: #6366f1;
    --gradient-end: #8b5cf6;
    --input-bg: #f8fafc;
    --input-border: #e2e8f0;
    --input-focus: #6366f1;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
    color: var(--text-primary);
    line-height: 1.5;
    min-height: 100vh;
}

.container {
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 2rem;
}

.form-wrapper {
    width: 100%;
    max-width: 1200px;
    background: white;
    border-radius: 24px;
    overflow: hidden;
    display: flex;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.15);
}

.form-side {
    flex: 1;
    padding: 3rem;
}

.image-side {
    flex: 1;
    background-image: url('https://images.unsplash.com/photo-1618005182384-a83a8bd57fbe?auto=format&fit=crop&w=1000&q=80');
    background-size: cover;
    background-position: center;
    position: relative;
}

.overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(45deg, rgba(99, 102, 241, 0.9) 0%, rgba(139, 92, 246, 0.9) 100%);
}

.form-container {
    max-width: 520px;
    margin: 0 auto;
}

h1 {
    font-size: 2.5rem;
    font-weight: 700;
    background: linear-gradient(to right, var(--gradient-start), var(--gradient-end));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 1rem;
}

.welcome-text {
    color: var(--text-secondary);
    margin-bottom: 2rem;
    font-size: 1.1rem;
}

.registration-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
}

.span-2 {
    grid-column: span 2;
}

.success-message {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem;
    background-color: #d1fae5;
    color: var(--success-color);
    border-radius: 1rem;
    margin-bottom: 1.5rem;
    animation: slideDown 0.3s ease-out;
}

.form-group {
    position: relative;
}

label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.input-group {
    position: relative;
}

input:not([type="radio"]) {
    width: 100%;
    padding: 0.875rem 1rem;
    padding-left: 2.75rem;
    border: 1.5px solid var(--input-border);
    border-radius: 1rem;
    font-size: 0.95rem;
    transition: all 0.2s ease;
    background: var(--input-bg);
    color: var(--text-primary);
}

input:not([type="radio"]):focus {
    outline: none;
    border-color: var(--input-focus);
    background: white;
    box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.1);
}

.input-icon {
    position: absolute;
    left: 0.875rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-secondary);
    pointer-events: none;
}

.gender-group {
    display: flex;
    gap: 1.5rem;
    padding: 0.5rem 0;
}

.radio-label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
    user-select: none;
    color: var(--text-secondary);
    transition: color 0.2s ease;
}

.radio-label:hover {
    color: var(--text-primary);
}

.radio-label input[type="radio"] {
    display: none;
}

.radio-custom {
    width: 1.25rem;
    height: 1.25rem;
    border: 2px solid var(--input-border);
    border-radius: 50%;
    display: inline-block;
    position: relative;
    transition: all 0.2s ease;
}

.radio-custom::after {
    content: '';
    width: 0.75rem;
    height: 0.75rem;
    background: var(--primary-color);
    border-radius: 50%;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) scale(0);
    transition: transform 0.2s ease;
}

.radio-label input[type="radio"]:checked + .radio-custom {
    border-color: var(--primary-color);
}

.radio-label input[type="radio"]:checked + .radio-custom::after {
    transform: translate(-50%, -50%) scale(1);
}

.toggle-password {
    position: absolute;
    right: 0.875rem;
    top: 50%;
    transform: translateY(-50%);
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    padding: 0.25rem;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: color 0.2s ease;
}

.toggle-password:hover {
    color: var(--text-primary);
}

.error-message {
    display: block;
    font-size: 0.75rem;
    color: var(--error-color);
    margin-top: 0.5rem;
    min-height: 1rem;
}

.password-strength {
    margin-top: 0.75rem;
}

.strength-bar {
    height: 4px;
    background-color: var(--input-border);
    border-radius: 2px;
    overflow: hidden;
}

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

.strength-fill.weak {
    width: 33.33%;
    background-color: var(--error-color);
}

.strength-fill.medium {
    width: 66.66%;
    background-color: var(--warning-color);
}

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

.strength-text {
    display: block;
    font-size: 0.75rem;
    color: var(--text-secondary);
    text-align: right;
    margin-top: 0.25rem;
}

.submit-btn {
    width: 100%;
    padding: 1rem 1.5rem;
    background: linear-gradient(to right, var(--gradient-start), var(--gradient-end));
    color: white;
    border: none;
    border-radius: 1rem;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.submit-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px -10px rgba(99, 102, 241, 0.5);
}

.submit-btn:active {
    transform: translateY(0);
}

.submit-btn svg {
    transition: transform 0.2s ease;
}

.submit-btn:hover svg {
    transform: translateX(4px);
}

.hidden {
    display: none;
}

@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-5px); }
    75% { transform: translateX(5px); }
}

.error input {
    border-color: var(--error-color);
    animation: shake 0.2s ease-in-out;
}

.error input:focus {
    box-shadow: 0 0 0 4px rgba(239, 68, 68, 0.1);
}

@media (max-width: 1024px) {
    .image-side {
        display: none;
    }
    
    .form-side {
        padding: 2rem;
    }

    .form-container {
        max-width: 100%;
    }
}

@media (max-width: 768px) {
    .registration-grid {
        grid-template-columns: 1fr;
    }

    .span-2 {
        grid-column: auto;
    }
}

@media (max-width: 640px) {
    .container {
        padding: 1rem;
    }

    .form-side {
        padding: 1.5rem;
    }

    h1 {
        font-size: 2rem;
    }

    .gender-group {
        flex-direction: column;
        gap: 0.75rem;
    }
}