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

body {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background: linear-gradient(135deg, #667eea, #764ba2);
    background-size: 200% 200%;
    animation: gradientBG 10s ease infinite;
}

@keyframes gradientBG {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

.container {
    width: 450px;
    background: white;
    border-radius: 20px;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.2);
    position: relative;
    overflow: hidden;
    height: auto;
    min-height: 500px;
}

.form-container {
    position: absolute;
    top: 0;
    width: 100%;
    height: 100%;
    padding: 40px;
    transition: all 0.6s cubic-bezier(0.68, -0.55, 0.265, 1.55);
    opacity: 0;
    z-index: 1;
}

.login-form {
    left: 0;
    opacity: 1;
    z-index: 2;
}

.signup-form {
    left: 100%;
}

.container.active .login-form {
    left: -100%;
    opacity: 0;
}

.container.active .signup-form {
    left: 0;
    opacity: 1;
    z-index: 3;
}

h2 {
    text-align: center;
    margin-bottom: 30px;
    color: #333;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.input-group {
    margin-bottom: 25px;
    position: relative;
    height: 60px;
    display: flex;
    align-items: center;
}

.input-group i {
    position: absolute;
    left: 20px;
    color: #777;
    z-index: 2;
    transition: all 0.3s ease;
}

.input-group input {
    width: 100%;
    padding: 20px 20px 10px 45px;
    border: 2px solid #eee;
    border-radius: 50px;
    font-size: 16px;
    transition: all 0.3s ease;
    background: transparent;
    outline: none;
    position: relative;
}

.input-group input:focus {
    border-color: #667eea;
}

.input-group input:focus + label,
.input-group input:not(:placeholder-shown) + label {
    top: 8px;
    left: 45px;
    font-size: 12px;
    color: #667eea;
    background: white;
    padding: 0 5px;
}

.input-group input:focus ~ i {
    color: #667eea;
}

.input-group label {
    position: absolute;
    left: 45px;
    top: 20px;
    color: #777;
    pointer-events: none;
    transition: all 0.3s ease;
}

.btn {
    width: 100%;
    padding: 15px;
    border: none;
    border-radius: 50px;
    background: linear-gradient(to right, #667eea, #764ba2);
    color: white;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    margin-top: 20px;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    background: linear-gradient(to right, #764ba2, #667eea);
}

.toggle-form {
    text-align: center;
    margin-top: 20px;
    color: #666;
}

.toggle-form a {
    color: #667eea;
    text-decoration: none;
    font-weight: bold;
    cursor: pointer;
    transition: color 0.3s ease;
}

.toggle-form a:hover {
    color: #764ba2;
    text-decoration: underline;
}

.social-login {
    margin: 25px 0;
    text-align: center;
}

.social-login p {
    color: #666;
    margin-bottom: 15px;
    position: relative;
}

.social-login p::before,
.social-login p::after {
    content: "";
    position: absolute;
    height: 1px;
    width: 30%;
    background: #ddd;
    top: 50%;
}

.social-login p::before {
    left: 0;
}

.social-login p::after {
    right: 0;
}

.social-icons {
    display: flex;
    justify-content: center;
    gap: 15px;
}

.social-icon {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: #f5f5f5;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
}

.social-icon:hover {
    background: #667eea;
    color: white;
    transform: translateY(-3px);
}

.row {
    display: flex;
    margin: 0 -10px;
}

.row > div {
    padding: 0 10px;
    flex: 1;
}

/* Uyarı mesajları */
.alert {
    padding: 10px 15px;
    border-radius: 4px;
    margin-bottom: 20px;
    font-size: 14px;
}

.alert-danger {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.alert-success {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

/* Küçük ekranlar için düzenleme */
@media (max-width: 480px) {
    .container {
        width: 95%;
        min-height: 400px;
    }
    
    .row {
        flex-direction: column;
        margin: 0;
    }
    
    .row > div {
        padding: 0;
    }
}