:root {
    /* Colors */
    --primary-color: #4f46e5;
    --primary-hover: #4338ca;
    --secondary-color: #10b981;
    --bg-color: #f3f4f6;
    --card-bg: #ffffff;
    --text-main: #111827;
    --text-muted: #6b7280;
    --border-color: #e5e7eb;
    --error-bg: #fef2f2;
    --error-text: #ef4444;
    
    /* Effects */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --radius-md: 0.5rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.5;
    height: 100vh;
    overflow: hidden;
}

.auth-container {
    display: flex;
    height: 100vh;
    width: 100%;
}

/* Card Section */
.auth-card {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    padding: 2rem 4rem;
    background-color: var(--card-bg);
    z-index: 10;
    max-width: 500px;
    box-shadow: var(--shadow-xl);
}

.auth-header {
    margin-bottom: 2rem;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 2rem;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

.auth-header h1 {
    font-size: 1.875rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    color: var(--text-main);
}

.auth-header p {
    color: var(--text-muted);
}

/* Form Elements */
.form-group {
    margin-bottom: 1.5rem;
}

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

input[type="email"],
input[type="password"] {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 1rem;
    transition: all 0.2s;
    font-family: inherit;
}

input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

/* Buttons */
.btn {
    display: inline-flex;
    justify-content: center;
    align-items: center;
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    font-weight: 600;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all 0.2s;
    border: none;
    font-family: inherit;
}

.btn-block {
    width: 100%;
}

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

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

.btn-primary:disabled {
    background-color: #9ca3af;
    cursor: not-allowed;
}

/* Spinner */
.spinner {
    border: 2px solid rgba(255,255,255,0.3);
    border-radius: 50%;
    border-top: 2px solid white;
    width: 1.25rem;
    height: 1.25rem;
    animation: spin 1s linear infinite;
    display: inline-block;
}

.hidden {
    display: none !important;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Alerts */
.alert {
    padding: 0.75rem 1rem;
    border-radius: var(--radius-md);
    margin-bottom: 1.5rem;
    font-size: 0.875rem;
}

.alert-error {
    background-color: var(--error-bg);
    color: var(--error-text);
    border: 1px solid #fecaca;
}

/* Footer links */
.auth-footer {
    margin-top: 1.5rem;
    text-align: center;
}

.forgot-link {
    color: var(--primary-color);
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: 500;
}

.forgot-link:hover {
    text-decoration: underline;
}

/* Illustration Section (Glassmorphism + Dynamic) */
.auth-illustration {
    flex: 2;
    background: linear-gradient(135deg, #4f46e5 0%, #7c3aed 100%);
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.illustration-content {
    position: relative;
    z-index: 10;
    color: white;
    text-align: center;
    max-width: 80%;
    padding: 3rem;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border-radius: var(--radius-xl);
    border: 1px solid rgba(255, 255, 255, 0.2);
    box-shadow: var(--shadow-lg);
}

.illustration-content h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.illustration-content p {
    font-size: 1.125rem;
    opacity: 0.9;
}

/* Decorative Shapes */
.shape {
    position: absolute;
    filter: blur(40px);
    border-radius: 50%;
    opacity: 0.6;
    animation: float 10s infinite alternate ease-in-out;
}

.shape-1 {
    width: 300px;
    height: 300px;
    background: #f43f5e;
    top: -50px;
    right: -50px;
    animation-delay: 0s;
}

.shape-2 {
    width: 400px;
    height: 400px;
    background: #0ea5e9;
    bottom: -100px;
    left: -100px;
    animation-delay: -5s;
}

.shape-3 {
    width: 200px;
    height: 200px;
    background: #10b981;
    top: 40%;
    left: 20%;
    animation-duration: 8s;
}

@keyframes float {
    0% { transform: translate(0, 0) scale(1); }
    100% { transform: translate(30px, -50px) scale(1.1); }
}

/* Responsive */
@media (max-width: 768px) {
    .auth-container {
        flex-direction: column;
    }
    
    .auth-illustration {
        display: none; /* Ẩn phần hình ảnh trên mobile để ưu tiên form */
    }
    
    .auth-card {
        max-width: 100%;
        padding: 2rem;
    }
}