/* ==========================================
   RESET E CONFIGURAÇÕES BÁSICAS
   ========================================== */

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: var(--font-size-base);
}

body {
    font-family: var(--font-body);
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    transition: background-color var(--transition-normal), color var(--transition-normal);
}

/* ==========================================
   HEADER E NAVEGAÇÃO
   ========================================== */

header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    width: 100%;
    background: var(--primary-color);
    color: var(--white);
    padding: var(--spacing-sm) var(--spacing-lg);
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: var(--z-header);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
}

header h1 {
    font-family: var(--font-heading);
    font-weight: 700;
    font-size: var(--font-size-xl);
}

nav {
    display: flex;
    gap: var(--spacing-lg);
}

nav a {
    color: var(--white);
    text-decoration: none;
    font-weight: 600;
    transition: color var(--transition-normal);
    position: relative;
}

nav a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-lighter);
    transition: width var(--transition-normal);
}

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

nav a:hover::after {
    width: 100%;
}

/* Botão de Toggle de Tema */
.theme-toggle {
    background: none;
    border: none;
    color: var(--white);
    font-size: 1.2rem;
    cursor: pointer;
    padding: var(--spacing-xs);
    transition: color var(--transition-fast), transform var(--transition-fast);
}

.theme-toggle:hover {
    color: var(--primary-lighter);
    transform: scale(1.1);
}

/* Menu Toggle (Mobile) */
.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--spacing-xs);
    z-index: 1001;
}

.menu-toggle span {
    width: 25px;
    height: 3px;
    background: var(--white);
    transition: all var(--transition-normal);
    border-radius: 2px;
}

.menu-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(6px, 6px);
}

.menu-toggle.active span:nth-child(2) {
    opacity: 0;
}

.menu-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(6px, -6px);
}

/* ==========================================
   MAIN CONTENT
   ========================================== */

main {
    max-width: 900px;
    margin: 100px auto var(--spacing-lg);
    padding: 0 var(--spacing-sm);
}

/* ... resto do código permanece igual ... *//* Media Queries para Mobile */
@media (max-width: 768px) {
    header {
        flex-wrap: wrap;
    }
    
    .menu-toggle {
        display: flex;
        flex-direction: column;
        gap: 4px;
        background: none;
        border: none;
        cursor: pointer;
        padding: 0.5rem;
    }
    
    .menu-toggle span {
        width: 25px;
        height: 3px;
        background: white;
        transition: all 0.3s ease;
    }
    
    nav {
        width: 100%;
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.3s ease;
    }
    
    nav.active {
        max-height: 300px;
    }
    
    nav a {
        display: block;
        margin: 1rem 0;
    }
    
    #introducao {
        flex-direction: column;
        text-align: center;
    }
}