/* ==========================================================
   PALETA — inspirada na dispersão da luz (tema de Ótica)
   ========================================================== */
:root {
    --bg: #F1F5F1;
    --surface: #FFFFFF;

    --ink: #1B2B27;
    --ink-soft: #4B5D58;

    --accent-teal: #2B7A68;
    --accent-violet: #5B52D6;
    --accent-amber: #E2903F;
    --accent-cream: #FCEE8C;
    --accent-dark: #16211E;

    --radius-pill: 999px;
    --radius-md: 14px;
    --shadow-soft: 0 2px 10px rgba(27, 43, 39, 0.08);
    --shadow-lift: 0 8px 20px rgba(27, 43, 39, 0.14);
}

:root[data-theme="dark"] {
    --bg: #101613;
    --surface: #1E2B27;
    --ink: #EAF2EE;
    --ink-soft: #B9C7C2;
    --accent-teal: #4FC3A9;
    --accent-violet: #8B83FF;
    --accent-amber: #F0A85A;
    --accent-cream: #FCEE8C;
    --accent-dark: #0A100D;
    --shadow-soft: 0 2px 10px rgba(0, 0, 0, 0.35);
    --shadow-lift: 0 8px 22px rgba(0, 0, 0, 0.45);
}

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

body {
    font-family: 'Inter', Arial, Helvetica, sans-serif;
    color: var(--ink);
    line-height: 1.6;
    transition: font-size 0.2s ease, background-color 0.25s ease, color 0.25s ease;
    background-color: var(--bg);
    background-image:
        radial-gradient(1100px 480px at 50% -12%, rgba(91, 82, 214, 0.10), transparent 60%),
        radial-gradient(800px 380px at 85% 0%, rgba(226, 144, 63, 0.08), transparent 55%),
        radial-gradient(700px 340px at 10% 5%, rgba(43, 122, 104, 0.08), transparent 55%);
    background-repeat: no-repeat;
}

:root[data-theme="dark"] body {
    background-image:
        radial-gradient(1100px 480px at 50% -12%, rgba(139, 131, 255, 0.16), transparent 60%),
        radial-gradient(800px 380px at 85% 0%, rgba(240, 168, 90, 0.10), transparent 55%),
        radial-gradient(700px 340px at 10% 5%, rgba(79, 195, 169, 0.12), transparent 55%);
}

.container {
    width: 90%;
    max-width: 1100px;
    margin: 0 auto;
}

/* --- Link "Pular para o conteúdo" --- */
.skip-link {
    position: absolute;
    left: -9999px;
    top: 0;
    background-color: var(--accent-teal);
    color: #fff;
    padding: 10px 16px;
    border-radius: 0 0 6px 0;
    font-weight: 600;
    text-decoration: none;
    z-index: 1000;
}

.skip-link:focus {
    left: 0;
}

a:focus-visible,
button:focus-visible {
    outline: 3px solid var(--accent-cream);
    outline-offset: 2px;
}

/* --- Barra de Acessibilidade --- */
.accessibility-bar {
    display: inline-block;
    background-color: var(--surface);
    border: 1px solid rgba(43, 122, 104, 0.15);
    border-top: none;
    border-left: none;
    border-radius: 0 0 18px 0;
    box-shadow: var(--shadow-soft);
    animation: slideInLeft 0.5s ease both;
}

.accessibility-container {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-wrap: wrap;
    padding: 10px 18px 10px 14px;
}

.acc-label {
    font-weight: 600;
    font-size: 0.8rem;
    color: var(--ink-soft);
    margin-right: 2px;
}

.acc-btn {
    background-color: var(--accent-teal);
    color: #fff;
    border: none;
    padding: 6px 14px;
    border-radius: var(--radius-pill);
    cursor: pointer;
    font-weight: 600;
    font-size: 0.82rem;
    transition: background-color 0.2s ease, color 0.2s ease, transform 0.15s ease;
}

.acc-btn:hover {
    background-color: var(--accent-cream);
    color: var(--ink);
    transform: translateY(-1px);
}

/* --- Header Principal --- */
.main-header {
    padding: 30px 0 0 0;
}

.header-inner {
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: center;
    width: 90%;
    max-width: 1100px;
    margin: 0 auto;
    padding-bottom: 28px;
    text-align: center;
    animation: headerIn 0.6s ease both;
}

.main-title {
    font-family: 'Space Grotesk', 'Inter', sans-serif;
    font-size: 3.2rem;
    font-weight: 700;
    color: var(--ink);
    letter-spacing: 0.3px;
}

.main-subtitle {
    margin-top: 6px;
    font-size: 1.05rem;
    color: var(--ink-soft);
    font-weight: 400;
}

.spectrum-line {
    width: 200px;
    height: 6px;
    margin: 20px auto 28px;
    border-radius: var(--radius-pill);
    background: linear-gradient(90deg, var(--accent-violet), var(--accent-teal), var(--accent-amber), var(--accent-cream), var(--accent-violet));
    background-size: 200% 100%;
    animation: spectrumShift 5s linear infinite;
}

/* --- Menu de Abas --- */
.tabs-nav {
    display: flex;
    justify-content: center;
    gap: 10px;
    flex-wrap: wrap;
}

.tab-btn {
    --tab-fill: var(--surface);
    color: var(--ink);
    border: 3px solid transparent;
    padding: 11px 24px;
    font-size: 1rem;
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    border-radius: var(--radius-pill);
    box-shadow: var(--shadow-soft);
    background-image:
        linear-gradient(var(--tab-fill), var(--tab-fill)),
        linear-gradient(90deg, var(--accent-violet), var(--accent-teal), var(--accent-amber), var(--accent-cream), var(--accent-violet));
    background-origin: padding-box, border-box;
    background-clip: padding-box, border-box;
    background-size: 100% 100%, 200% 100%;
    animation: spectrumShift 5s linear infinite;
    transition: color 0.2s ease, box-shadow 0.2s ease, transform 0.15s ease;
}

.tab-btn:hover {
    --tab-fill: var(--accent-cream);
    color: var(--ink);
    transform: translateY(-2px) scale(1.02);
    box-shadow: var(--shadow-lift);
}

.tab-btn.active {
    border-color: transparent;
    background-image: linear-gradient(90deg, var(--accent-violet), var(--accent-teal), var(--accent-amber), var(--accent-cream), var(--accent-violet));
    background-origin: border-box;
    background-clip: border-box;
    background-size: 200% 100%;
    animation: spectrumShift 5s linear infinite;
    color: #fff;
    text-shadow: 0 1px 3px rgba(0, 0, 0, 0.35);
    box-shadow: var(--shadow-lift);
}

.hamburger-btn {
    display: none;
    position: absolute;
    top: 6px;
    right: 0;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 8px;
    flex-direction: column;
    gap: 5px;
}

.hamburger-btn span {
    display: block;
    width: 28px;
    height: 4px;
    background-color: var(--accent-teal);
    border-radius: 2px;
    transition: transform 0.3s ease, opacity 0.3s ease;
}

.hamburger-btn[aria-expanded="true"] span:nth-child(1) { transform: translateY(9px) rotate(45deg); }
.hamburger-btn[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.hamburger-btn[aria-expanded="true"] span:nth-child(3) { transform: translateY(-9px) rotate(-45deg); }

/* --- Conteúdo das Seções --- */
.tab-content {
    background-color: var(--surface);
    margin: 25px 0;
    padding: 30px;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-soft);
    animation: fadeIn 0.25s ease;
}

.tab-content[hidden] { display: none; }

.tab-content h2 {
    font-family: 'Space Grotesk', 'Inter', sans-serif;
    color: var(--accent-teal);
    border-bottom: 3px solid var(--accent-cream);
    padding-bottom: 8px;
    margin-bottom: 20px;
}

/* --- Cards de tópico (Introdução à Ótica) --- */
.topic-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 28px;
    margin-top: 26px;
    align-items: flex-start;
}

.topic-card {
    flex: 1 1 calc(50% - 14px);
    min-width: 240px;
    animation: cardIn 0.5s ease backwards;
}

.topic-card:nth-child(1) { animation-delay: 0.05s; }
.topic-card:nth-child(2) { animation-delay: 0.15s; }
.topic-card:nth-child(3) { animation-delay: 0.25s; }
.topic-card:nth-child(4) { animation-delay: 0.35s; }

.topic-card h3 {
    font-family: 'Space Grotesk', 'Inter', sans-serif;
    color: var(--accent-teal);
    font-size: 1.1rem;
    margin-bottom: 12px;
}

/* --- Card de destaque (fake news) --- */
.insight-card {
    background-color: var(--bg);
    border: 1px solid rgba(91, 82, 214, 0.18);
    border-radius: var(--radius-md);
    padding: 26px 22px;
    margin-top: 34px;
    animation: cardIn 0.5s ease backwards;
    animation-delay: 0.1s;
    transition: box-shadow 0.2s ease, transform 0.2s ease;
}

.insight-card:hover {
    box-shadow: var(--shadow-lift);
    transform: translateY(-3px);
}

.insight-card > * + * { margin-top: 20px; }

.insight-card h3 {
    font-family: 'Space Grotesk', 'Inter', sans-serif;
    color: var(--accent-violet);
    font-size: 1.25rem;
}

.insight-card > p {
    color: var(--ink-soft);
    font-size: 0.97rem;
}

/* ==========================================================
   FLASHCARDS — usados em toda imagem do site.
   Frente: imagem + legenda. Verso: explicação.
   Hover: expande. Clique/Enter/Espaço: vira e desvira.
   ========================================================== */
.flashcard {
    position: relative;
    width: 100%;
    height: 230px;
    perspective: 1200px;
    cursor: pointer;
    transition: transform 0.25s ease;
}

.flashcard:hover,
.flashcard:focus-visible {
    transform: scale(1.07);
    z-index: 5;
    outline: none;
}

.flashcard:focus-visible .flashcard-inner {
    outline: 3px solid var(--accent-cream);
    outline-offset: 3px;
    border-radius: var(--radius-md);
}

.flashcard-inner {
    position: relative;
    width: 100%;
    height: 100%;
    transition: transform 0.6s;
    transform-style: preserve-3d;
}

.flashcard.is-flipped .flashcard-inner {
    transform: rotateY(180deg);
}

.flashcard-face {
    position: absolute;
    inset: 0;
    backface-visibility: hidden;
    border-radius: var(--radius-md);
    overflow: hidden;
    box-shadow: var(--shadow-soft);
    display: flex;
    flex-direction: column;
}

.flashcard-front {
    background-color: var(--surface);
}

.flashcard-front img {
    flex: 1;
    width: 100%;
    min-height: 0;
    object-fit: contain;
    background-color: var(--bg);
    display: block;
}

.flashcard-caption {
    flex-shrink: 0;
    padding: 8px 12px;
    font-size: 0.8rem;
    color: var(--ink-soft);
    font-style: italic;
    text-align: center;
    background-color: var(--surface);
}

.flashcard-back {
    transform: rotateY(180deg);
    background: linear-gradient(135deg, var(--accent-teal), var(--accent-violet));
    color: #fff;
    padding: 18px;
    justify-content: center;
    overflow-y: auto;
}

.flashcard-back p {
    font-size: 0.9rem;
    line-height: 1.5;
}

.flashcard-back p + p {
    margin-top: 10px;
}

.flashcard-back strong {
    color: var(--accent-cream);
}

/* Tamanhos usados nos cards de tópico (ritmo visual variado) */
.flashcard--lg { height: 240px; }
.flashcard--sm { height: 190px; }
.flashcard--wide { height: 190px; }
.flashcard--md { height: 210px; }

/* --- Cartões dos Projetos --- */
.project-card {
    position: relative;
    background-color: var(--bg);
    border: 1px solid rgba(43, 122, 104, 0.18);
    border-radius: var(--radius-md);
    padding: 30px 20px 20px;
    margin-top: 30px;
    margin-bottom: 25px;
    transition: box-shadow 0.2s ease, transform 0.2s ease;
    animation: cardIn 0.4s ease backwards;
}

.project-card:nth-of-type(1) { animation-delay: 0.05s; }
.project-card:nth-of-type(2) { animation-delay: 0.15s; }
.project-card:nth-of-type(3) { animation-delay: 0.25s; }

.project-card:hover {
    box-shadow: var(--shadow-lift);
    transform: translateY(-3px);
}

.project-card > * + * { margin-top: 22px; }

.project-card h3 {
    font-family: 'Space Grotesk', 'Inter', sans-serif;
    color: var(--accent-violet);
}

.project-badge {
    position: absolute;
    top: -14px;
    left: 24px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 34px;
    height: 34px;
    padding: 0 4px;
    border-radius: var(--radius-pill);
    color: #fff;
    font-family: 'Space Grotesk', 'Inter', sans-serif;
    font-weight: 700;
    font-size: 0.85rem;
    box-shadow: var(--shadow-soft);
}

.project-card:nth-of-type(3n+1) .project-badge { background-color: var(--accent-teal); }
.project-card:nth-of-type(3n+2) .project-badge { background-color: var(--accent-violet); }
.project-card:nth-of-type(3n+3) .project-badge {
    background-color: var(--accent-amber);
    color: var(--ink);
}

/* Bloco "Tecnologia relacionada" / "Legado até hoje" */
.real-world-card__label {
    display: block;
    width: fit-content;
    font-size: 0.72rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: var(--accent-violet);
    background-color: rgba(91, 82, 214, 0.12);
    padding: 4px 10px;
    border-radius: var(--radius-pill);
    margin-bottom: 10px;
}

/* Mídias */
.media-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 15px;
}

.media-grid--single {
    grid-template-columns: minmax(0, 420px);
    justify-content: center;
}

.video-box {
    background: var(--accent-dark);
    padding: 12px;
    border-radius: 10px;
}

.video-wrapper { position: relative; }

.video-wrapper video {
    width: 100%;
    max-height: 400px;
    display: block;
    border-radius: 6px;
}

.video-play-btn {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 64px;
    height: 64px;
    border-radius: 50%;
    border: none;
    background-color: rgba(255, 255, 255, 0.92);
    color: var(--accent-dark);
    font-size: 1.4rem;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    box-shadow: var(--shadow-lift);
    transition: transform 0.15s ease, background-color 0.15s ease;
    animation: pulseGlow 2.4s ease-in-out infinite;
}

.video-play-btn:hover {
    background-color: var(--accent-cream);
    transform: translate(-50%, -50%) scale(1.08);
    animation-play-state: paused;
}

.video-play-btn.is-hidden { display: none; }

.video-box .media-caption {
    color: var(--accent-cream);
    font-size: 0.85rem;
    font-style: italic;
    margin-top: 10px;
}

/* --- Blocos expansíveis (accordions) --- */
.info-accordion {
    border: 1px solid rgba(43, 122, 104, 0.15);
    border-radius: 10px;
    background-color: var(--surface);
    overflow: hidden;
}

.info-accordion summary {
    cursor: pointer;
    list-style: none;
    padding: 13px 16px;
    font-weight: 600;
    color: var(--accent-teal);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
}

.info-accordion summary::-webkit-details-marker { display: none; }

.info-accordion summary::after {
    content: '+';
    flex-shrink: 0;
    font-size: 1.3rem;
    line-height: 1;
    color: var(--accent-violet);
    transition: transform 0.25s ease;
}

.info-accordion[open] summary::after { transform: rotate(45deg); }

.info-accordion summary:focus-visible {
    outline: 3px solid var(--accent-cream);
    outline-offset: -3px;
    border-radius: 6px;
}

.info-accordion p {
    padding: 0 16px 16px;
    color: var(--ink-soft);
    font-size: 0.95rem;
}

.info-accordion p + p {
    padding-top: 0;
    margin-top: -8px;
}

/* --- Tabela comparativa --- */
.table-wrapper { overflow-x: auto; }

.sector-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.88rem;
    min-width: 480px;
}

.sector-table th,
.sector-table td {
    padding: 10px 14px;
    border-bottom: 1px solid rgba(43, 122, 104, 0.15);
    text-align: left;
}

.sector-table th {
    font-family: 'Space Grotesk', 'Inter', sans-serif;
    color: var(--accent-teal);
}

.sector-table tbody tr:last-child td { border-bottom: none; }

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
}

/* --- Rodapé --- */
.site-footer {
    margin-top: 40px;
    padding: 26px 0 40px;
    text-align: center;
    border-top: 1px solid rgba(43, 122, 104, 0.15);
}

.site-footer p {
    color: var(--ink-soft);
    font-size: 0.88rem;
    line-height: 1.7;
}

.site-footer code {
    background-color: rgba(43, 122, 104, 0.12);
    color: var(--accent-teal);
    padding: 2px 6px;
    border-radius: 6px;
    font-size: 0.85em;
    font-family: 'Space Grotesk', monospace;
}

/* --- Movimento reduzido --- */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        transition: none !important;
        animation: none !important;
    }
    .flashcard-inner { transition: none !important; }
}

/* --- Keyframes --- */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(6px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes cardIn {
    from { opacity: 0; transform: translateY(16px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes headerIn {
    from { opacity: 0; transform: translateY(-10px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes slideInLeft {
    from { opacity: 0; transform: translateX(-14px); }
    to { opacity: 1; transform: translateX(0); }
}

@keyframes spectrumShift {
    0% { background-position: 0% 50%; }
    100% { background-position: 200% 50%; }
}

@keyframes pulseGlow {
    0%, 100% { box-shadow: var(--shadow-lift); }
    50% { box-shadow: 0 8px 22px rgba(43, 122, 104, 0.55); }
}

/* --- RESPONSIVIDADE PARA CELULAR --- */
@media (max-width: 768px) {
    .main-title { font-size: 2rem; }
    .main-subtitle { font-size: 0.9rem; }

    .hamburger-btn { display: flex; }

    .tabs-nav {
        display: none;
        flex-direction: column;
        width: 100%;
        padding-bottom: 4px;
    }

    .tabs-nav.show { display: flex; }

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

    .tab-content { padding: 18px; }

    .topic-card { flex: 1 1 100%; }

    .accessibility-container {
        padding: 12px 16px;
        gap: 10px;
        row-gap: 10px;
    }

    .acc-label { width: 100%; margin-right: 0; }

    .acc-btn {
        padding: 9px 16px;
        font-size: 0.88rem;
        min-height: 40px;
    }
}