/* ========================================
   CSS VARIABLES (THEME SYSTEM)
   ======================================== */
:root {
    --primary-color: #3498db;
    --primary-dark: #0097a7;

    --bg-color: #f4f4f4;
    --bg-secondary: #ffffff;
    --bg-tertiary: #e0e0e0;

    --text-color: #333;
    --text-gray: #666;

    --header-bg: #222;
    --border-color: #ccc;

    /* NOVO (menu profissional) */
    --nav-bg: #ffffff;
    --nav-text: #333;

    --transition: 0.3s;
    --border-radius: 6px;
    --touch-target: 44px;
}

/* 🌙 DARK MODE */
html[data-theme="dark"] {
    --primary-color: #1abc9c;

    --bg-color: #121212;
    --bg-secondary: #1a1a1a;
    --bg-tertiary: #2a2a2a;

    --text-color: #ffffff;
    --text-gray: #bbbbbb;

    --header-bg: #1a1a1a;
    --border-color: #333;

    /* NOVO (menu dark) */
    --nav-bg: #2a2a2a;
    --nav-text: #ffffff;
}

/* ========================================
   RESET & BASE STYLES
   ======================================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

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

/* ========================================
   HEADER & NAVIGATION
   ======================================== */
header {
    background: var(--header-bg);
    color: white;
    padding: 15px;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

/* MENU PROFISSIONAL */
nav ul {
    display: flex;
    list-style: none;
    background: var(--nav-bg);
    padding: 6px 12px;
    border-radius: 10px;
    gap: 10px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
}

nav ul li {
    margin: 0;
}

/* LINKS COMO BOTÕES */
nav a {
    color: var(--nav-text);
    text-decoration: none;
    font-weight: 600;
    padding: 8px 14px;
    border-radius: 6px;
    transition: all var(--transition);
    display: block;
}

/* HOVER MODERNO */
nav a:hover {
    background: var(--primary-color);
    color: white;
    transform: translateY(-1px);
}

/* FOCO ACESSÍVEL */
nav a:focus,
nav a:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* ========================================
   NAVIGATION BUTTONS
   ======================================== */
.nav-buttons {
    display: flex;
    gap: 10px;
}

.nav-buttons button {
    padding: 8px 16px;
    cursor: pointer;
    min-height: var(--touch-target);
    min-width: var(--touch-target);
}

/* ========================================
   SECTIONS
   ======================================== */
section {
    padding: 100px 20px;
    min-height: 100vh;
    max-width: 1200px;
    margin: 0 auto;
    margin-top: 60px;
}

section:first-of-type {
    margin-top: 60px;
}

/* ========================================
   FORMS & INPUTS
   ======================================== */
form {
    display: flex;
    flex-direction: column;
    max-width: 400px;
    gap: 15px;
}

input,
textarea {
    margin: 0;
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    font-family: inherit;
    font-size: 16px;
    transition: border-color var(--transition), box-shadow var(--transition);
    min-height: var(--touch-target);
    background: var(--bg-secondary);
    color: var(--text-color);
}

input::placeholder,
textarea::placeholder {
    color: var(--text-gray);
}

input:focus,
textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 5px rgba(0, 188, 212, 0.3);
}

textarea {
    resize: vertical;
    min-height: 120px;
}

/* ========================================
   BUTTONS
   ======================================== */
button {
    padding: 12px 20px;
    border: none;
    background: var(--primary-color);
    color: white;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: background var(--transition);
    font-weight: 500;
    min-height: var(--touch-target);
    font-size: 16px;
}

button:hover {
    background: var(--primary-dark);
}

button:focus,
button:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

button:active {
    transform: scale(0.98);
}

/* ========================================
   ACCESSIBILITY
   ======================================== */
:focus:not(:focus-visible) {
    outline: none;
}

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}

/* ========================================
   MOBILE MENU
   ======================================== */
#menuBtn {
    display: none;
    background: transparent;
    color: white;
    border: none;
    padding: 10px;
    cursor: pointer;
    font-size: 24px;
    min-height: var(--touch-target);
}

#menuBtn:hover {
    background: rgba(255, 255, 255, 0.1);
}

/* ========================================
   RESPONSIVE DESIGN
   ======================================== */
@media (max-width: 768px) {
    header {
        padding: 10px;
    }

    nav ul {
        display: none;
        flex-direction: column;
        background: var(--nav-bg);
        position: absolute;
        top: 60px;
        right: 0;
        width: 200px;
        padding: 10px;
    }

    nav ul li {
        padding: 10px;
    }

    nav ul.show {
        display: flex;
    }

    #menuBtn {
        display: inline-block;
    }

    section {
        padding: 80px 15px;
        margin-top: 60px;
    }

    form {
        max-width: 100%;
    }

    input,
    textarea,
    button {
        font-size: 16px;
    }
}

@media (max-width: 480px) {
    section {
        padding: 60px 10px;
        min-height: auto;
    }

    nav ul {
        width: 100%;
        right: 0;
    }

    nav ul li {
        padding: 15px 20px;
    }
}