* {
    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;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.container {
    width: 100%;
    max-width: 400px;
    margin: 0 auto;
}

.login-card {
    background: white;
    border-radius: 12px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
    padding: 40px 30px;
    position: relative;
    overflow: hidden;
}

.login-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, #667eea, #764ba2);
}

.logo {
    text-align: center;
    margin-bottom: 30px;
}

.logo h1 {
    color: #333;
    font-size: 28px;
    font-weight: 600;
    margin-bottom: 8px;
}

.logo p {
    color: #666;
    font-size: 14px;
}

.login-form {
    width: 100%;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 6px;
    color: #333;
    font-weight: 500;
    font-size: 14px;
}

.form-group input {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid #e1e5e9;
    border-radius: 8px;
    font-size: 16px;
    transition: border-color 0.3s ease, box-shadow 0.3s ease;
    background-color: #fafafa;
}

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

.form-options {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 25px;
}

.checkbox-container {
    display: flex;
    align-items: center;
    cursor: pointer;
    font-size: 14px;
    color: #666;
}

.checkbox-container input[type="checkbox"] {
    width: auto;
    margin-right: 8px;
    transform: scale(1.1);
}

.forgot-password {
    color: #667eea;
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    transition: color 0.3s ease;
}

.forgot-password:hover {
    color: #5a6fd8;
}

.login-btn {
    width: 100%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    padding: 14px;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    margin-bottom: 20px;
}

.login-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.3);
}

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

.divider {
    text-align: center;
    margin: 20px 0;
    position: relative;
}

.divider::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 0;
    right: 0;
    height: 1px;
    background: #e1e5e9;
}

.divider span {
    background: white;
    padding: 0 15px;
    color: #666;
    font-size: 14px;
}

.social-login {
    margin-bottom: 25px;
}

.social-btn {
    width: 100%;
    padding: 12px;
    border: 2px solid #e1e5e9;
    border-radius: 8px;
    background: white;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.3s ease;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.social-btn:hover {
    border-color: #d1d5db;
    background: #f9fafb;
}

.google-btn {
    color: #db4437;
}

.github-btn {
    color: #333;
}

.signup-link {
    text-align: center;
    color: #666;
    font-size: 14px;
}

.signup-link a {
    color: #667eea;
    text-decoration: none;
    font-weight: 600;
}

.signup-link a:hover {
    text-decoration: underline;
}

/* Responsive Design */
@media (max-width: 480px) {
    .container {
        padding: 0;
    }
    
    .login-card {
        margin: 0;
        border-radius: 0;
        min-height: 100vh;
        display: flex;
        flex-direction: column;
        justify-content: center;
    }
    
    .logo h1 {
        font-size: 24px;
    }
}

/* Animation for form validation */
.form-group input.error {
    border-color: #ef4444;
    background-color: #fef2f2;
}

.form-group input.error:focus {
    border-color: #ef4444;
    box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.1);
}

/* Loading state for button */
.login-btn.loading {
    opacity: 0.7;
    cursor: not-allowed;
}

.login-btn.loading::after {
    content: '';
    width: 20px;
    height: 20px;
    border: 2px solid transparent;
    border-top: 2px solid white;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    display: inline-block;
    margin-left: 10px;
}

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