body {
    margin: 0;
    font-family: 'Merriweather', serif;
    background-color: #0f0f0f;
    color: #f0f0f0;
    line-height: 1.6;
    scroll-behavior: smooth;
}

header {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: #1a1a1a;
    padding: 1rem 2rem;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
    z-index: 1000;
}

header h1 {
    margin: 0;
    font-family: 'Inter', sans-serif;
    font-size: 1.8rem;
    color: #b67d4c;
}

.subtitle {
    margin-top: 4px;
    font-size: 1rem;
    color: #999;
}

nav {
    margin-top: 120px;
    background: linear-gradient(135deg, #1a1a1a, #1a1a1a);
    padding: 1rem 2rem;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.2);
}

nav ul {
    list-style: none;
    padding: 0;
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    justify-content: center;
}

nav a {
    text-decoration: none;
    color: #5e5eff;
    /* Azul original */
    font-family: 'Arial', sans-serif;
    font-size: 1rem;
    font-weight: 500;
    transition: all 0.3s ease;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

nav a:hover,
nav a:focus {
    color: #b67d4c;
    background-color: rgba(255, 255, 255, 0.1);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    outline: none;
}

nav a:focus {
    border: 2px solid #b67d4c;
}

main {
    padding: 2rem;
    padding-top: 8rem;
    max-width: 800px;
    margin: auto;
}

section.intro p {
    font-style: italic;
    font-size: small;
    text-align: justify;
}

section.concept {
    margin: 2rem 0;
    border-left: 4px solid #5e5eff;
    padding-left: 1rem;
}

section.concept h2 {
    cursor: pointer;
    color: #b67d4c;
    margin-bottom: 0.5rem;
    transition: color 0.3s ease;
}

section.concept h2:hover {
    color: #5e5eff;
}

section .content {
    display: none;
    margin-top: 0.5rem;
    padding-left: 0.5rem;
    border-left: 2px solid #333;
    animation: fadeIn 0.5s ease-in-out;
}


section.intro {
    display: flex;
}

.controls {
    margin: 2rem 0;
    text-align: center;
}

.controls button {
    padding: 0.6rem 1.2rem;
    background-color: #5e5eff;
    color: #fff;
    border: none;
    border-radius: 10px;
    cursor: pointer;
    transition: background 0.3s;
}

.controls button:hover {
    background-color: #4a4ae0;
}

.comment-box {
    margin-top: 3rem;
}

.comment-box h3 {
    margin-bottom: 0.5rem;
}

.comment-box {
    margin-top: 2rem;
    text-align: center;
    padding: 1rem;
}

.comment-box textarea {
    width: 100%;
    max-width: 600px;
    min-height: 120px;
    padding: 1rem;
    font-size: 1rem;
    font-family: 'Inter', sans-serif;
    background: #1a1a1a;
    border: 1px solid #444;
    color: #eee;
    border-radius: 8px;
    resize: vertical;
    box-sizing: border-box;
    margin: 0 auto;
    display: block;
}

#enviar {
    background: linear-gradient(135deg, #4CAF50, #45a049);
    color: #fff;
    border: none;
    padding: 14px 28px;
    font-size: 16px;
    border-radius: 8px;
    cursor: pointer;
    font-weight: bold;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.2);
    transition: 0.3s ease-in-out;
}

#enviar:hover {
    background: linear-gradient(135deg, #45a049, #3e8e41);
    transform: scale(1.05);
    box-shadow: 0 6px 10px rgba(0, 0, 0, 0.3);
}

.mensagem {
    margin-top: 20px;
    font-size: 18px;
    color: #333;
    display: none;
    animation: fadeIn 0.5s ease-in-out;
}

footer {
    margin-top: 4rem;
    padding: 2rem;
    text-align: center;
    color: #666;
    font-style: italic;
    border-top: 1px solid #333;
}

@media (max-width: 550px) {
    main {
        padding-top: 10rem;
    }

}

@media (max-width: 390px) {
    main {
        padding-top: 11rem;
    }

}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}