/* ═══════════════════════════════════════════════════════
   style.css — FrontBooks Landing Page
   Tema: Retrô Terminal / TRON / High-Contrast Industrial
════════════════════════════════════════════════════════ */

/* ── VARIÁVEIS ── */
:root {
     --black: #000000;
     --orange: #FF6600;
     --orange-dim: #cc5200;
     --orange-glow: rgba(255, 102, 0, 0.18);
     --white: #ffffff;
     --grey-light: #cccccc;
     --grey-mid: #888888;
     --grey-dark: #1a1a1a;
     --border: rgba(255, 102, 0, 0.35);
     --font-main: 'Roboto', sans-serif;
     --font-mono: 'Roboto Mono', monospace;
     --nav-h: 64px;
}

/* ── RESET ── */
*,
*::before,
*::after {
     box-sizing: border-box;
     margin: 0;
     padding: 0;
}

html {
     scroll-behavior: smooth;
     font-size: 16px;
}

body {
     background-color: var(--black);
     color: var(--white);
     font-family: var(--font-main);
     line-height: 1.6;
     overflow-x: hidden;
}

a {
     color: inherit;
     text-decoration: none;
}

/* ── UTILITÁRIOS ── */
.accent {
     color: var(--orange);
}

/* ══════════════════════════════════════════════════════
   NAV BAR FIXA
══════════════════════════════════════════════════════ */
.navbar {
     position: fixed;
     top: 0;
     left: 0;
     width: 100%;
     height: var(--nav-h);
     background: rgba(0, 0, 0, 0.92);
     border-bottom: 1px solid var(--border);
     backdrop-filter: blur(6px);
     z-index: 999;
}

.nav-inner {
     max-width: 1100px;
     margin: 0 auto;
     height: 100%;
     padding: 0 24px;
     display: flex;
     align-items: center;
     justify-content: flex-start;
}

.nav-left {
     display: flex;
     align-items: center;
     gap: 28px;
}

.nav-logo {
     font-family: var(--font-mono);
     font-size: 1rem;
     font-weight: 700;
     letter-spacing: 0.08em;
     color: var(--white);
     user-select: none;
}

.nav-links {
     display: flex;
     align-items: center;
     gap: 28px;
}

.nav-links a {
     font-family: var(--font-mono);
     font-size: 0.78rem;
     letter-spacing: 0.1em;
     color: var(--grey-light);
     transition: color 0.2s;
}

.nav-links a:hover {
     color: var(--orange);
}

.btn-nav {
     font-family: var(--font-mono);
     font-size: 0.75rem;
     font-weight: 700;
     letter-spacing: 0.12em;
     color: var(--orange) !important;
     border: 1px solid var(--orange);
     padding: 8px 18px;
     transition: background 0.2s, color 0.2s;
}

.btn-nav:hover {
     background: var(--orange);
     color: var(--black) !important;
}

/* ══════════════════════════════════════════════════════
   BOTÃO PRIMÁRIO
══════════════════════════════════════════════════════ */
.btn-primary {
     display: inline-block;
     font-family: var(--font-mono);
     font-size: 0.82rem;
     font-weight: 700;
     letter-spacing: 0.12em;
     color: var(--black);
     background: var(--orange);
     border: 2px solid var(--orange);
     padding: 12px 28px;
     cursor: pointer;
     transition: background 0.2s, color 0.2s, box-shadow 0.2s;
     white-space: nowrap;
}

.btn-primary:hover {
     background: transparent;
     color: var(--orange);
     box-shadow: 0 0 18px var(--orange-glow);
}

/* ══════════════════════════════════════════════════════
   HERO SECTION
══════════════════════════════════════════════════════ */
.hero {
     position: relative;
     min-height: 100vh;
     display: flex;
     align-items: center;
     justify-content: center;
     padding: calc(var(--nav-h) + 40px) 24px 80px;
     overflow: hidden;
}

.hero-grid-bg {
     position: absolute;
     inset: 0;
     background-image:
          linear-gradient(rgba(255, 102, 0, 0.06) 1px, transparent 1px),
          linear-gradient(90deg, rgba(255, 102, 0, 0.06) 1px, transparent 1px);
     background-size: 48px 48px;
     pointer-events: none;
     z-index: 0;
}

.hero::before {
     content: '';
     position: absolute;
     inset: 0;
     background: radial-gradient(ellipse at center, transparent 40%, rgba(0, 0, 0, 0.85) 100%);
     z-index: 1;
     pointer-events: none;
}

.hero-content {
     position: relative;
     z-index: 2;
     text-align: center;
     max-width: 820px;
}

.hero-label {
     font-family: var(--font-mono);
     font-size: 0.78rem;
     letter-spacing: 0.2em;
     color: var(--orange);
     margin-bottom: 20px;
     text-transform: uppercase;
}

.hero-title {
     font-family: var(--font-main);
     font-size: clamp(2.2rem, 6vw, 4.5rem);
     font-weight: 900;
     line-height: 1.1;
     letter-spacing: -0.01em;
     text-transform: uppercase;
     color: var(--white);
     margin-bottom: 12px;
}

.hero-title-sub {
     font-family: var(--font-mono);
     font-size: clamp(0.9rem, 2vw, 1.1rem);
     font-weight: 700;
     letter-spacing: 0.15em;
     color: var(--orange);
     text-transform: uppercase;
     margin-bottom: 24px;
}

.hero-sub {
     font-size: 1rem;
     color: var(--grey-light);
     font-weight: 300;
     margin-bottom: 40px;
     line-height: 1.7;
}

.corner {
     position: absolute;
     width: 28px;
     height: 28px;
     z-index: 2;
     pointer-events: none;
}

.c-tl {
     top: calc(var(--nav-h) + 20px);
     left: 20px;
     border-top: 2px solid var(--orange);
     border-left: 2px solid var(--orange);
}

.c-tr {
     top: calc(var(--nav-h) + 20px);
     right: 20px;
     border-top: 2px solid var(--orange);
     border-right: 2px solid var(--orange);
}

.c-bl {
     bottom: 20px;
     left: 20px;
     border-bottom: 2px solid var(--orange);
     border-left: 2px solid var(--orange);
}

.c-br {
     bottom: 20px;
     right: 20px;
     border-bottom: 2px solid var(--orange);
     border-right: 2px solid var(--orange);
}

/* ══════════════════════════════════════════════════════
   SEÇÃO E-BOOK (PRODUTO ÚNICO)
══════════════════════════════════════════════════════ */
.ebook-section {
     padding: 80px 24px 100px;
}

.ebook-inner {
     max-width: 1100px;
     margin: 0 auto;
     display: grid;
     grid-template-columns: 320px 1fr;
     gap: 72px;
     align-items: start;
}

/* ── CAPA DO LIVRO ── */
.book-cover-wrap {
     position: sticky;
     top: calc(var(--nav-h) + 32px);
     display: flex;
     flex-direction: column;
     align-items: center;
     gap: 20px;
}

.book-cover-frame {
     position: relative;
     width: 100%;
     aspect-ratio: 4 / 5;
     border: 1px solid var(--border);
     overflow: hidden;
     box-shadow: 0 0 40px rgba(255, 102, 0, 0.15), 8px 8px 0 rgba(255, 102, 0, 0.2);
     transition: box-shadow 0.3s;
}

.book-cover-frame:hover {
     box-shadow: 0 0 60px rgba(255, 102, 0, 0.3), 8px 8px 0 rgba(255, 102, 0, 0.4);
}

.book-cover-img {
     width: 100%;
     height: 100%;
     object-fit: cover;
     display: block;
}

.book-badge {
     position: absolute;
     top: 16px;
     right: 16px;
     font-family: var(--font-mono);
     font-size: 0.65rem;
     font-weight: 700;
     letter-spacing: 0.15em;
     color: var(--black);
     background: var(--orange);
     padding: 4px 10px;
}

.book-meta {
     display: flex;
     flex-direction: column;
     gap: 8px;
     width: 100%;
}

.book-meta-item {
     font-family: var(--font-mono);
     font-size: 0.75rem;
     letter-spacing: 0.1em;
     color: var(--grey-mid);
     border-bottom: 1px solid rgba(255, 255, 255, 0.07);
     padding-bottom: 8px;
}

/* ── DETALHES DO LIVRO ── */
.book-details {
     display: flex;
     flex-direction: column;
     gap: 28px;
}

.section-label {
     font-family: var(--font-mono);
     font-size: 0.78rem;
     letter-spacing: 0.2em;
     color: var(--orange);
     text-transform: uppercase;
}

.book-main-title {
     font-size: clamp(1.6rem, 3vw, 2.4rem);
     font-weight: 900;
     line-height: 1.15;
     letter-spacing: -0.01em;
     text-transform: uppercase;
     color: var(--white);
}

.book-desc {
     font-size: 0.97rem;
     color: var(--grey-light);
     font-weight: 300;
     line-height: 1.75;
     max-width: 620px;
}

/* ── SUMÁRIO / ÍNDICE ── */
.summary-wrap {
     display: flex;
     flex-direction: column;
     gap: 0;
     border: 1px solid var(--border);
     background: var(--grey-dark);
     position: relative;
}

.summary-wrap::before {
     content: '';
     position: absolute;
     left: 0;
     top: 0;
     bottom: 0;
     width: 4px;
     background: var(--orange);
     opacity: 0.7;
}

.summary-label {
     font-family: var(--font-mono);
     font-size: 0.68rem;
     letter-spacing: 0.2em;
     color: var(--orange);
     padding: 14px 20px 14px 24px;
     border-bottom: 1px solid rgba(255, 102, 0, 0.2);
     background: rgba(255, 102, 0, 0.05);
}

.summary-chapter {
     display: flex;
     align-items: flex-start;
     gap: 20px;
     padding: 20px 24px;
     border-bottom: 1px solid rgba(255, 255, 255, 0.06);
     transition: background 0.2s;
}

.summary-chapter:last-child {
     border-bottom: none;
}

.summary-chapter:hover {
     background: rgba(255, 102, 0, 0.05);
}

.chapter-num {
     font-family: var(--font-mono);
     font-size: 1.4rem;
     font-weight: 700;
     color: var(--orange);
     opacity: 0.5;
     line-height: 1.2;
     min-width: 36px;
     flex-shrink: 0;
}

.chapter-body {
     display: flex;
     flex-direction: column;
     gap: 6px;
}

.chapter-title {
     font-size: 0.97rem;
     font-weight: 700;
     letter-spacing: 0.02em;
     color: var(--white);
     text-transform: uppercase;
}

.chapter-desc {
     font-family: var(--font-mono);
     font-size: 0.75rem;
     color: var(--grey-mid);
     line-height: 1.6;
     letter-spacing: 0.02em;
}

/* ── BLOCO DE COMPRA ── */
.buy-block {
     display: flex;
     align-items: center;
     gap: 32px;
     padding: 28px 0;
     border-top: 1px solid rgba(255, 255, 255, 0.08);
     flex-wrap: wrap;
}

.buy-price-wrap {
     display: flex;
     flex-direction: column;
     gap: 4px;
}

.buy-label {
     font-family: var(--font-mono);
     font-size: 0.65rem;
     letter-spacing: 0.18em;
     color: var(--grey-mid);
     text-transform: uppercase;
}

.card-price {
     font-family: var(--font-mono);
     font-size: 1.8rem;
     font-weight: 700;
     color: var(--orange);
     letter-spacing: 0.04em;
}

.btn-buy {
     font-size: 0.88rem;
     padding: 16px 36px;
}

/* ══════════════════════════════════════════════════════
   FOOTER
══════════════════════════════════════════════════════ */
.footer {
     background: var(--grey-dark);
     border-top: 1px solid var(--border);
     padding: 60px 24px;
     text-align: center;
}

.footer-inner {
     max-width: 600px;
     margin: 0 auto;
     display: flex;
     flex-direction: column;
     align-items: center;
     gap: 16px;
}

.footer-desc {
     font-size: 0.92rem;
     color: var(--grey-mid);
     font-weight: 300;
}

.footer-contacts {
     display: flex;
     flex-direction: column;
     gap: 12px;
     align-items: center;
}

.footer-contacts a {
     font-family: var(--font-mono);
     font-size: 0.88rem;
     color: var(--orange);
     letter-spacing: 0.05em;
     display: flex;
     align-items: center;
     gap: 10px;
     padding: 8px 20px;
     border: 1px solid rgba(255, 102, 0, 0.2);
     transition: border-color 0.2s, background 0.2s, color 0.2s;
     min-width: 280px;
     justify-content: center;
}

.footer-contacts a:hover {
     border-color: var(--orange);
     background: var(--orange-glow);
     color: var(--white);
}

.contact-icon {
     font-size: 1rem;
     color: var(--orange);
     line-height: 1;
}

.footer-copy {
     font-family: var(--font-mono);
     font-size: 0.68rem;
     letter-spacing: 0.12em;
     color: var(--grey-mid);
     margin-top: 16px;
}

/* ══════════════════════════════════════════════════════
   RESPONSIVIDADE
══════════════════════════════════════════════════════ */
@media (max-width: 900px) {
     .ebook-inner {
          grid-template-columns: 1fr;
          gap: 48px;
     }

     .book-cover-wrap {
          position: static;
          max-width: 320px;
          margin: 0 auto;
     }
}

@media (max-width: 768px) {
     .nav-links a:not(.btn-nav) {
          display: none;
     }

     .hero-title {
          font-size: clamp(1.9rem, 9vw, 3rem);
     }

     .hero-sub {
          font-size: 0.92rem;
     }

     .buy-block {
          flex-direction: column;
          align-items: flex-start;
          gap: 20px;
     }

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

@media (max-width: 480px) {
     .hero-label {
          font-size: 0.65rem;
     }

     .section-label {
          font-size: 0.65rem;
     }

     .ebook-section {
          padding: 60px 16px 80px;
     }

     .summary-chapter {
          padding: 16px 16px 16px 20px;
          gap: 14px;
     }

     .chapter-num {
          font-size: 1.1rem;
     }
}