/* General Styles */
:root {
    --primary: #00bcd4; /* Cyan */
    --secondary: #0097a7; /* Darker Cyan */
    --accent: #ffeb3b; /* Yellow for highlights */
    --background: #1a1a2e; /* Dark Blue */
    --surface: #1f283e; /* Slightly lighter dark blue */
    --text-color: #e0f7fa; /* Light Cyan */
    --glass-bg: rgba(255, 255, 255, 0.05);
    --glass-border: rgba(255, 255, 255, 0.1);
    --shadow: rgba(0, 0, 0, 0.3);
}

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

body {
    font-family: 'Poppins', sans-serif;
    background-color: var(--background);
    color: var(--text-color);
    line-height: 1.6;
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

a {
    color: var(--primary);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'JetBrains Mono', monospace;
    color: var(--primary);
    margin-bottom: 1rem;
}

p {
    margin-bottom: 1rem;
}

/* Navigation Bar */
nav {
    background-color: var(--surface);
    padding: 15px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: 0 2px 10px var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--glass-border);
}

.nav-left {
    display: flex;
    align-items: center;
}

.nav-back {
    color: var(--text-color);
    margin-right: 20px;
    font-size: 1.1rem;
    transition: color 0.3s ease;
}

.nav-back:hover {
    color: var(--accent);
}

.nav-title {
    font-family: 'JetBrains Mono', monospace;
    font-size: 1.2rem;
    color: var(--text-color);
}

.nav-title strong {
    color: var(--primary);
}

.nav-counter {
    background-color: var(--primary);
    color: var(--background);
    padding: 5px 10px;
    border-radius: 5px;
    font-weight: bold;
    font-family: 'JetBrains Mono', monospace;
}

/* Hero Section */
.hero {
    background: linear-gradient(45deg, var(--background), var(--surface));
    padding: 60px 20px;
    text-align: center;
    position: relative;
    overflow: hidden;
    border-bottom: 2px solid var(--primary);
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle at center, rgba(0,188,212,0.1) 0%, transparent 70%);
    animation: pulse 10s infinite alternate;
    z-index: 0;
}

@keyframes pulse {
    0% { transform: scale(0.8); opacity: 0.5; }
    100% { transform: scale(1.2); opacity: 0.7; }
}

.hero > * {
    position: relative;
    z-index: 1;
}

.hero-badge {
    background-color: var(--accent);
    color: var(--background);
    padding: 5px 15px;
    border-radius: 20px;
    font-weight: bold;
    display: inline-block;
    margin-bottom: 15px;
    font-size: 0.9rem;
    text-transform: uppercase;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 10px;
    color: var(--text-color);
}

.hero-desc {
    font-size: 1.1rem;
    color: var(--text-color);
    max-width: 800px;
    margin: 0 auto;
}

/* Resumo Section */
.resumo-section {
    background-color: var(--surface);
    padding: 30px;
    border-radius: 10px;
    margin-top: 30px;
    box-shadow: 0 5px 15px var(--shadow);
    border: 1px solid var(--glass-border);
}

.resumo-section h2 {
    color: var(--primary);
    margin-bottom: 1rem;
}

/* Concepts Grid */
.concepts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
    margin-top: 30px;
}

.concept-card {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 10px;
    padding: 20px;
    text-align: center;
    box-shadow: 0 4px 8px var(--shadow);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.concept-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 20px var(--shadow);
}

.concept-icon {
    font-size: 2.5rem;
    margin-bottom: 10px;
    color: var(--accent);
}

.concept-title {
    font-family: 'JetBrains Mono', monospace;
    font-size: 1.3rem;
    color: var(--primary);
    margin-bottom: 5px;
}

.concept-desc {
    font-size: 0.95rem;
    color: var(--text-color);
}

/* Attention Box */
.attention-box {
    background-color: #3e2723; /* Darker orange/brown for attention */
    border-left: 5px solid var(--accent);
    padding: 20px;
    margin-top: 30px;
    border-radius: 5px;
    box-shadow: 0 2px 8px var(--shadow);
}

.attention-box h3 {
    color: var(--accent);
    margin-bottom: 10px;
    display: flex;
    align-items: center;
}

.attention-box h3::before {
    content: '⚡';
    margin-right: 10px;
}

.attention-box ul {
    list-style: none;
    padding-left: 0;
}

.attention-box li {
    margin-bottom: 8px;
    color: #ffe082; /* Lighter yellow for list items */
}

/* Simulator Section */
.simulator-section {
    background-color: var(--surface);
    padding: 30px;
    border-radius: 10px;
    margin-top: 30px;
    box-shadow: 0 5px 15px var(--shadow);
    border: 1px solid var(--glass-border);
    text-align: center;
}

.simulator-section h2 {
    color: var(--primary);
    margin-bottom: 1.5rem;
}

.simulator-canvas {
    width: 100%;
    height: 350px;
    background-color: #2a2a3a;
    border: 1px solid var(--primary);
    border-radius: 8px;
    margin-bottom: 20px;
}

.simulator-controls .btn {
    background-color: var(--primary);
    color: var(--background);
    border: none;
    padding: 10px 20px;
    margin: 0 5px;
    border-radius: 5px;
    cursor: pointer;
    font-size: 1rem;
    transition: background-color 0.3s ease, transform 0.2s ease;
}

.simulator-controls .btn:hover {
    background-color: var(--secondary);
    transform: translateY(-2px);
}

.simulator-controls .btn.active {
    background-color: var(--accent);
    color: var(--background);
    box-shadow: 0 0 10px var(--accent);
}

/* Questions Section */
.questions-section {
    margin-top: 30px;
    background-color: var(--surface);
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 5px 15px var(--shadow);
    border: 1px solid var(--glass-border);
}

.questions-section h2 {
    color: var(--primary);
    margin-bottom: 1.5rem;
}

.question-card {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 8px;
    padding: 20px;
    margin-bottom: 20px;
    box-shadow: 0 2px 5px var(--shadow);
}

.question-source {
    font-size: 0.85rem;
    color: #9e9e9e;
    margin-bottom: 10px;
}

.question-text {
    font-size: 1.1rem;
    margin-bottom: 15px;
}

.options {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin-bottom: 15px;
}

.option {
    background-color: #3a475e; /* Darker shade for options */
    color: var(--text-color);
    border: 1px solid #5c6b8a;
    padding: 12px 15px;
    border-radius: 5px;
    text-align: left;
    cursor: pointer;
    transition: background-color 0.3s ease, border-color 0.3s ease;
}

.option:hover:not(:disabled) {
    background-color: #4a5b78;
    border-color: var(--primary);
}

.option.correct {
    background-color: #4CAF50; /* Green */
    border-color: #4CAF50;
    color: white;
}

.option.incorrect {
    background-color: #f44336; /* Red */
    border-color: #f44336;
    color: white;
}

.option:disabled {
    cursor: not-allowed;
}

.feedback {
    margin-top: 10px;
    padding: 10px;
    background-color: #2a2a3a;
    border-left: 4px solid var(--primary);
    border-radius: 4px;
    color: var(--text-color);
    font-size: 0.95rem;
    display: none;
}

.feedback.show {
    display: block;
}

/* Footer Navigation */
.footer-nav {
    display: flex;
    justify-content: space-between;
    margin-top: 40px;
    padding-top: 20px;
    border-top: 1px solid var(--glass-border);
}

.nav-btn {
    background-color: var(--primary);
    color: var(--background);
    padding: 12px 25px;
    border-radius: 5px;
    font-weight: bold;
    transition: background-color 0.3s ease, transform 0.2s ease;
}

.nav-btn:hover {
    background-color: var(--secondary);
    transform: translateY(-2px);
}

.nav-btn.index {
    background-color: #607d8b; /* Grey-blue for index */
}

.nav-btn.index:hover {
    background-color: #455a64;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-left {
        flex-direction: column;
        align-items: flex-start;
    }

    .nav-back {
        margin-bottom: 10px;
    }

    .hero h1 {
        font-size: 2.2rem;
    }

    .hero-desc {
        font-size: 1rem;
    }

    .concepts-grid {
        grid-template-columns: 1fr;
    }

    .footer-nav {
        flex-direction: column;
        gap: 15px;
    }

    .nav-btn {
        text-align: center;
        width: 100%;
    }
}