:root {
    --bg-color: #ffffff;
    --text-color: #2C3E50;
    --surface-color: #F8F9FA;
    --primary-color: #2ECC71;
    --secondary-color: #3498DB;
    --header-bg: #ffffff;
    --shadow: 0 4px 6px rgba(0,0,0,0.1);
}


body.dark-mode {
    --bg-color: #1a1a1a;
    --text-color: #ecf0f1;
    --surface-color: #2c3e50;
    --header-bg: #111111;
    --shadow: 0 4px 6px rgba(0,0,0,0.5);
}


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

html {
    scroll-behavior: smooth;
}

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    transition: background-color 0.3s ease, color 0.3s ease;
    line-height: 1.6;
}


header {
    background-color: var(--header-bg);
    box-shadow: var(--shadow);
    position: fixed; 
    width: 100%;
    top: 0;
    z-index: 1000;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 5%;
    transition: background-color 0.3s ease;
}

.logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
}

nav ul {
    list-style: none;
    display: flex;
    gap: 1.5rem;
}

nav a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: color 0.3s;
}

nav a:hover {
    color: var(--primary-color);
}

#theme-toggle {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    margin-left: 1rem;
}


main {
    margin-top: 80px; 
}

section {
    padding: 4rem 5%;
    text-align: center;
}

h2 {
    font-size: 2rem;
    margin-bottom: 2rem;
}


#hero {
    background-color: var(--surface-color);
    padding: 6rem 5%;
}

#hero h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.btn-primary, .btn-secondary {
    display: inline-block;
    padding: 0.8rem 2rem;
    border-radius: 5px;
    text-decoration: none;
    font-weight: bold;
    margin-top: 1rem;
    border: none;
    cursor: pointer;
    transition: transform 0.2s, filter 0.2s;
}

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

.btn-secondary {
    background-color: var(--secondary-color);
    color: white;
    width: 100%;
    font-size: 1.1rem;
}

.btn-primary:hover, .btn-secondary:hover {
    filter: brightness(0.9);
    transform: translateY(-2px); 
}


.cards-container {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
}

.card {
    background-color: var(--surface-color);
    padding: 2rem;
    border-radius: 8px;
    box-shadow: var(--shadow);
    transition: transform 0.3s;
}

.card:hover {
    transform: translateY(-5px);
}


#contato form {
    max-width: 500px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

input {
    padding: 1rem;
    border: 1px solid #ccc;
    border-radius: 5px;
    font-size: 1rem;
    width: 100%;
}

@media (max-width: 768px) {

    nav ul {
        display: none; 
    }
    
    #hero h1 {
        font-size: 2rem;
    }
}

@media (min-width: 769px) {

    .cards-container {
        grid-template-columns: repeat(2, 1fr);
    }
}

footer {
    background-color: var(--header-bg);
    padding: 2rem;
    text-align: center;
    box-shadow: 0 -4px 6px rgba(0,0,0,0.05);
}