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

body {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    background: linear-gradient(45deg, #1a2980, #26d0ce);
    padding: 20px;
}

.main-title {
    color: white;
    font-size: 2.5em;
    margin-bottom: 30px;
    text-align: center;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
    animation: fadeIn 1s ease-in;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.container {
    position: relative;
    width: 800px;
    height: 500px;
    background: white;
    border-radius: 20px;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.2);
    overflow: hidden;
}

.container .content {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
}

.container .content .form {
    position: relative;
    width: 50%;
    height: 100%;
    padding: 40px;
    transition: 0.5s;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.container .content .form.signin {
    background: white;
    transition: 0.5s;
}

.container .content .form.search {
    background: #2196f3;
    transition: 0.5s;
}

.form h2 {
    font-size: 24px;
    margin-bottom: 30px;
    color: #333;
}

.search h2 {
    color: white;
}

.form input, .form select {
    width: 100%;
    padding: 10px;
    margin: 10px 0;
    border: 1px solid #ccc;
    border-radius: 5px;
    outline: none;
    font-size: 16px;
    background-color: white;
    box-sizing: border-box;
}

/* Estilo para el placeholder del select */
.form select option:first-child {
    color: #999;
}

/* Estilo para las opciones reales */
.form select option:not(:first-child) {
    color: #000;
}

.form select {
    appearance: none;
    -webkit-appearance: none;
    -moz-appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' fill='%23333' viewBox='0 0 16 16'%3E%3Cpath d='M7.247 11.14L2.451 5.658C1.885 5.013 2.345 4 3.204 4h9.592a1 1 0 0 1 .753 1.659l-4.796 5.48a1 1 0 0 1-1.506 0z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 10px center;
    padding-right: 30px;
    cursor: pointer;
}

.form select::-ms-expand {
    display: none;
}

.form select:focus {
    border-color: #2196f3;
    box-shadow: 0 0 5px rgba(33, 150, 243, 0.2);
}

/* Color para el texto de placeholder del select no seleccionado */
.form select {
    color: #555555;
}

/* Al seleccionar una opción real, el texto del select cambia a negro */
.form select.selected {
    color: #000;
}

.form button {
    width: 100%;
    padding: 12px;
    margin: 15px 0;
    background: #2196f3;
    border: none;
    border-radius: 5px;
    color: white;
    font-size: 16px;
    cursor: pointer;
    transition: 0.3s;
}

.search button {
    background: white;
    color: #2196f3;
}

.form button:hover {
    opacity: 0.8;
}

.toggle-container {
    position: absolute;
    top: 0;
    left: 50%;
    width: 50%;
    height: 100%;
    overflow: hidden;
    transition: 0.5s;
    background: #2196f3;
    z-index: 1000;
}

.toggle-container.active {
    transform: translateX(-100%);
}

.toggle {
    position: relative;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 40px;
    text-align: center;
    color: white;
}

.toggle h2 {
    font-size: 24px;
    margin-bottom: 10px;
}

.toggle p {
    font-size: 16px;
    margin-bottom: 20px;
}

.toggle button {
    padding: 12px 35px;
    background: transparent;
    border: 2px solid white;
    border-radius: 5px;
    color: white;
    font-size: 16px;
    cursor: pointer;
    transition: 0.3s;
}

.toggle button:hover {
    background: white;
    color: #2196f3;
}

.radio-options {
    display: flex;
    flex-direction: column;
    justify-content: space-between; 
    width: 100%; 
    margin-right: 15px;
    padding: 20px 0;
}

.radio-label {
    display: flex;
    align-items: center;
    color: white;
    margin: 5px 0;
    cursor: pointer;
}

.radio-label input[type="radio"] {
    width: auto;
    margin-right: 10px;
    cursor: pointer;
}

@media (max-width: 850px) {
    .container {
        width: 90%;
        max-width: 700px;
    }
    
    .main-title {
        font-size: 2.5em;
        margin-bottom: 20px;
    }
}

@media (max-width: 480px) {
    .main-title {
        font-size: 2em;
    }

    .form h2 {
        font-size: 20px;
    }

    .form input,
    .form button {
        font-size: 14px;
    }
}