body {
    font-family: 'Inter', sans-serif;
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    background-color: var(--background-color);
    color: var(--text-color);
    transition: background-color 0.3s, color 0.3s;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 20px;
    background-color: var(--header-background-color);
    color: var(--header-text-color);
}

header .logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

header .logo img {
    width: 40px;
    height: 40px;
    border-radius: 50%;
}

header h1 {
    font-size: 20px;
    margin: 0;
}

nav ul {
    list-style: none;
    display: flex;
    gap: 15px;
    margin: 0;
    padding: 0;
}

nav ul li a {
    text-decoration: none;
    color: var(--header-link-color);
    font-weight: bold;
    transition: color 0.3s;
}

nav ul li a:hover {
    color: var(--header-link-hover-color);
}

nav ul li a.active {
    text-decoration: underline;
    color: var(--header-link-hover-color);
}

.signup-section {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 80vh;
    padding: 20px;
    background-color: var(--background-color);
}

.signup-section h2 {
    font-size: 24px;
    margin-bottom: 20px;
    color: var(--primary-color);
}

.signup-form {
    width: 100%;
    max-width: 500px;
    background-color: var(--container-background-color);
    border-radius: 8px;
    padding: 30px;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
    transition: background-color 0.3s, box-shadow 0.3s;
}

.signup-form .form-group {
    margin-bottom: 15px;
}

.signup-form label {
    display: block;
    margin-bottom: 5px;
    font-weight: bold;
    color: var(--text-color);
}

.signup-form input,
.signup-form select {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--input-border-color);
    border-radius: 5px;
    font-size: 14px;
    outline: none;
    transition: border-color 0.3s;
    background-color: var(--input-background-color);
    color: var(--text-color);
}

.signup-form input:focus,
.signup-form select:focus {
    border-color: var(--primary-color);
}

.signup-form .btn {
    width: 100%;
    padding: 10px;
    background-color: var(--primary-color);
    color: var(--button-text-color);
    border: none;
    border-radius: 5px;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    transition: background-color 0.3s;
}

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

.signup-form p {
    margin-top: 10px;
    text-align: center;
}

.signup-form p a {
    color: var(--primary-color);
    text-decoration: none;
}

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

footer {
    text-align: center;
    padding: 10px 0;
    background-color: var(--footer-background-color);
    color: var(--footer-text-color);
    font-size: 12px;
}

:root {
    --background-color: #f9f9f9;
    --text-color: #333;
    --primary-color: #6c63ff;
    --primary-hover-color: #574bdf;
    --header-background-color: #6c63ff;
    --header-text-color: #fff;
    --header-link-color: #fff;
    --header-link-hover-color: #d1cfff;
    --container-background-color: #fff;
    --input-background-color: #fff;
    --input-border-color: #ddd;
    --button-text-color: #fff;
    --footer-background-color: #333;
    --footer-text-color: #fff;
}

[data-theme="dark"] {
    --background-color: #121212;
    --text-color: #e0e0e0;
    --primary-color: #81c784;
    --primary-hover-color: #66bb6a;
    --header-background-color: #2e7d32;
    --header-text-color: #fff;
    --header-link-color: #fff;
    --header-link-hover-color: #aed581;
    --container-background-color: #1e1e1e;
    --input-background-color: #2a2a2a;
    --input-border-color: #3a3a3a;
    --button-text-color: #000;
    --footer-background-color: #1c1c1c;
    --footer-text-color: #fff;
}

@media (max-width: 768px) {
    .signup-section {
        padding: 15px;
    }

    .signup-form {
        padding: 20px;
    }
}

@media (max-width: 480px) {
    .signup-form {
        padding: 15px;
    }

    .signup-form label,
    .signup-form input {
        font-size: 12px;
    }

    .signup-form .btn {
        font-size: 14px;
    }
}