/* English Grammar for Spanish Speakers, interactive web book stylesheet */

:root {
  --navy: #0F4C5C;
  --coral: #C75146;
  --gold: #F7B538;
  --cream: #F8F4E3;
  --soft: #F4F1EA;
  --research: #EAF3F4;
  --charcoal: #2D2D2D;
  --slate: #4A5568;
  --muted: #707A85;
  --rule: #E5E5E5;
  --white: #FFFFFF;

  --bg: #FAF8F2;
  --surface: #FFFFFF;
  --surface-alt: #F4F1EA;
  --text: #2D2D2D;
  --text-muted: #707A85;
  --border: #E5E5E5;
}

[data-theme="dark"] {
  --bg: #0E1B22;
  --surface: #15252D;
  --surface-alt: #1E323B;
  --text: #F2EBD8;
  --text-muted: #9DA8AF;
  --border: rgba(255,255,255,0.12);
  --soft: #1E323B;
  --research: #1A3540;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: Calibri, "Helvetica Neue", Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img { max-width: 100%; }
a { color: var(--coral); }
a:hover { color: var(--navy); }
[data-theme="dark"] a:hover { color: var(--gold); }

.skip-link {
  position: absolute; left: -9999px; top: 0; padding: 8px 12px;
  background: var(--navy); color: var(--gold); z-index: 1000;
}
.skip-link:focus { left: 8px; top: 8px; }

.container { max-width: 1180px; margin: 0 auto; padding: 0 24px; }

/* ===== HEADER / NAV ===== */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
}
.nav-shell {
  display: flex; align-items: center; gap: 18px;
  padding: 12px 24px;
  max-width: 1180px; margin: 0 auto;
  flex-wrap: wrap;
}
.brand {
  display: flex; align-items: center; gap: 10px;
  text-decoration: none; color: inherit;
}
.brand-mark {
  background: var(--navy); color: var(--gold);
  width: 40px; height: 40px; border-radius: 6px;
  display: flex; align-items: center; justify-content: center;
  font-family: Georgia, serif; font-weight: 700; font-size: 16px;
  letter-spacing: 0.06em;
  flex-shrink: 0;
}
.brand-mark-img {
  height: 92px; width: auto; display: block; flex-shrink: 0;
  background: #fff; border-radius: 8px; padding: 4px;
}
.site-footer .brand-mark-img { height: 112px; }
@media (max-width: 800px) {
  .brand-mark-img { height: 70px; }
  .site-footer .brand-mark-img { height: 92px; }
}
.brand-copy { display: flex; flex-direction: column; line-height: 1.05; }
.brand-title { font-family: Georgia, serif; font-weight: 700; font-size: 16px; color: var(--navy); }
[data-theme="dark"] .brand-title { color: var(--gold); }
.brand-subtitle { font-size: 11.5px; color: var(--muted); font-style: italic; margin-top: 2px; }

.nav-menu {
  display: flex; gap: 18px; align-items: center;
  flex: 1; justify-content: center;
}
.nav-menu a {
  text-decoration: none; color: var(--text); font-size: 14px;
  font-weight: 600; padding: 6px 4px;
  border-bottom: 2px solid transparent; transition: color 0.15s, border-color 0.15s;
}
.nav-menu a:hover { color: var(--coral); border-bottom-color: var(--coral); }
.back-link { color: var(--coral) !important; font-weight: 700 !important; }
.back-link:hover { color: var(--navy) !important; }
[data-theme="dark"] .back-link:hover { color: var(--gold) !important; }

.nav-actions { display: flex; align-items: center; gap: 10px; }

.lang-toggle {
  display: inline-flex;
  border: 1px solid var(--border); border-radius: 6px; overflow: hidden;
  background: var(--surface);
}
.lang-toggle button {
  background: transparent; color: var(--text);
  border: none; padding: 6px 12px;
  font-family: Georgia, serif; font-size: 12px; font-weight: 700; letter-spacing: 0.08em;
  cursor: pointer; transition: background 0.15s, color 0.15s;
}
.lang-toggle button:hover { background: var(--soft); }
.lang-toggle button.active { background: var(--navy); color: var(--gold); }

.theme-toggle {
  background: transparent; color: var(--text); border: 1px solid var(--border);
  padding: 6px 14px; border-radius: 6px;
  font-family: Calibri, sans-serif; font-size: 13px; font-weight: 600; cursor: pointer;
}
.theme-toggle:hover { background: var(--soft); }

/* ===== HERO ===== */
.hero {
  padding: 64px 0 48px;
  background: linear-gradient(180deg, var(--soft) 0%, var(--bg) 100%);
  border-bottom: 1px solid var(--border);
}
.hero-container { max-width: 880px; }
.eyebrow {
  font-family: Georgia, serif; font-size: 11px; font-weight: 700;
  letter-spacing: 0.18em; text-transform: uppercase; color: var(--coral);
  margin: 0 0 8px;
}
.hero h1 {
  font-family: Georgia, serif; font-weight: 700;
  font-size: clamp(34px, 5vw, 52px); line-height: 1.1;
  color: var(--navy); margin: 0 0 14px;
}
[data-theme="dark"] .hero h1 { color: var(--gold); }
.hero-lead {
  font-size: 17px; color: var(--text); line-height: 1.6;
  max-width: 720px; margin: 0 0 24px;
}
.hero-actions {
  display: flex; flex-wrap: wrap; gap: 12px; margin-bottom: 32px;
}
.btn {
  display: inline-block; padding: 12px 22px; border-radius: 6px;
  font-family: Georgia, serif; font-weight: 700; font-size: 15px;
  text-decoration: none; cursor: pointer; border: 2px solid transparent;
  transition: transform 0.15s, background 0.15s, color 0.15s, border-color 0.15s;
}
.btn-primary { background: var(--navy); color: var(--gold); }
.btn-primary:hover { background: var(--coral); color: var(--cream); transform: translateY(-1px); }
.btn-secondary { background: transparent; color: var(--navy); border-color: var(--navy); }
.btn-secondary:hover { background: var(--navy); color: var(--gold); }
[data-theme="dark"] .btn-secondary { color: var(--gold); border-color: var(--gold); }
[data-theme="dark"] .btn-secondary:hover { background: var(--gold); color: var(--navy); }

.hero-stats {
  list-style: none; padding: 0; margin: 0;
  display: grid; grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 14px;
}
.hero-stats li {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: 8px; padding: 14px 16px;
  display: flex; flex-direction: column; gap: 4px;
}
.hero-stats strong {
  font-family: Georgia, serif; font-size: 26px; font-weight: 700;
  color: var(--navy); line-height: 1;
}
[data-theme="dark"] .hero-stats strong { color: var(--gold); }
.hero-stats span {
  font-size: 12px; color: var(--muted); letter-spacing: 0.04em;
}

/* ===== SECTIONS ===== */
.section { padding: 56px 0; }
.section h2 {
  font-family: Georgia, serif; font-weight: 700;
  font-size: clamp(24px, 3vw, 32px); line-height: 1.2;
  color: var(--navy); margin: 0 0 8px;
}
[data-theme="dark"] .section h2 { color: var(--gold); }
.section .lead {
  color: var(--slate); font-size: 16px; line-height: 1.6; max-width: 720px;
  margin: 8px 0 28px;
}
[data-theme="dark"] .section .lead { color: var(--text-muted); }

/* ===== LIBRARY ===== */
.library-tools {
  display: flex; flex-direction: column; gap: 14px; margin-bottom: 22px;
}
#lesson-search {
  width: 100%; padding: 12px 16px; border-radius: 6px;
  border: 1px solid var(--border);
  background: var(--surface); color: var(--text);
  font-size: 15px; font-family: Calibri, sans-serif;
}
#lesson-search:focus { outline: 2px solid var(--coral); outline-offset: 2px; }
.chip-row { display: flex; flex-wrap: wrap; gap: 8px; }
.chip {
  background: transparent; border: 1px solid var(--border);
  padding: 7px 14px; border-radius: 999px;
  font-family: Calibri, sans-serif; font-size: 13px; font-weight: 600;
  cursor: pointer; color: var(--text); transition: all 0.15s;
}
.chip:hover { background: var(--soft); border-color: var(--coral); color: var(--coral); }
.chip.is-active { background: var(--navy); color: var(--gold); border-color: var(--navy); }

.lesson-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 14px;
}
.lesson-card {
  background: var(--surface); border: 1px solid var(--border); border-left: 4px solid var(--gold);
  border-radius: 8px; padding: 18px 20px;
  cursor: pointer; transition: transform 0.15s, box-shadow 0.15s, border-left-color 0.15s;
  display: flex; flex-direction: column; gap: 4px;
}
.lesson-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 24px rgba(15,76,92,0.10);
  border-left-color: var(--coral);
}
.lesson-index {
  display: inline-block; align-self: flex-start;
  font-family: Georgia, serif; font-size: 11px; font-weight: 700;
  letter-spacing: 0.12em; color: var(--coral);
}
.lesson-cat {
  font-family: Georgia, serif; font-size: 10.5px; font-weight: 700;
  letter-spacing: 0.12em; text-transform: uppercase; color: var(--slate);
  margin-top: 2px;
}
[data-theme="dark"] .lesson-cat { color: var(--text-muted); }
.lesson-card h3 {
  font-family: Georgia, serif; font-size: 17px; line-height: 1.3;
  color: var(--navy); margin: 6px 0 10px;
}
[data-theme="dark"] .lesson-card h3 { color: var(--gold); }
.lesson-cta {
  margin-top: auto; font-size: 13px; font-weight: 700;
  color: var(--coral); letter-spacing: 0.04em;
}
.empty-state {
  text-align: center; padding: 32px; color: var(--muted); font-style: italic;
}

/* ===== READER ===== */
.reader-wrap { background: var(--surface-alt); }
.reader-empty {
  text-align: center; padding: 48px 24px;
  background: var(--surface); border-radius: 8px;
  border: 1px dashed var(--border);
}
.reader-empty h3 {
  font-family: Georgia, serif; color: var(--navy);
  font-size: 22px; margin: 8px 0 0;
}
[data-theme="dark"] .reader-empty h3 { color: var(--gold); }

.reader {
  background: var(--surface);
  border-radius: 12px;
  padding: 26px 32px 36px;
  box-shadow: 0 14px 36px rgba(15,76,92,0.08);
  border: 1px solid var(--border);
  position: relative;
}
.reader-bar {
  display: flex; align-items: center; justify-content: space-between;
  gap: 12px; padding-bottom: 16px; margin-bottom: 22px;
  border-bottom: 1px solid var(--border);
  flex-wrap: wrap;
}
.reader-bar.bottom {
  border-bottom: none; border-top: 1px solid var(--border);
  margin-top: 28px; margin-bottom: 0; padding-top: 18px; padding-bottom: 0;
}
.reader-bar-right { display: flex; gap: 8px; align-items: center; }
.reader-counter {
  font-family: Georgia, serif; font-size: 13px;
  color: var(--slate); font-weight: 600;
}
[data-theme="dark"] .reader-counter { color: var(--text-muted); }
.reader-nav-btn {
  background: var(--soft); color: var(--navy);
  border: 1px solid var(--border); border-radius: 6px;
  padding: 8px 14px; font-family: Calibri, sans-serif;
  font-size: 13px; font-weight: 600; cursor: pointer;
  text-decoration: none; transition: background 0.15s, color 0.15s;
}
.reader-nav-btn:hover:not(:disabled) { background: var(--navy); color: var(--gold); }
.reader-nav-btn:disabled { opacity: 0.4; cursor: not-allowed; }
[data-theme="dark"] .reader-nav-btn { color: var(--gold); }
.reader-close {
  background: var(--cream); color: var(--charcoal);
  border: 1px solid var(--border); border-radius: 50%;
  width: 36px; height: 36px;
  font-size: 22px; line-height: 1; cursor: pointer;
  display: flex; align-items: center; justify-content: center;
}
.reader-close:hover { background: var(--coral); color: var(--cream); border-color: var(--coral); }

/* ===== Chapter content ===== */
.ch-header {
  margin-bottom: 22px; padding-bottom: 14px;
  border-bottom: 2px solid var(--coral);
}
.ch-num {
  display: inline-block; background: var(--coral); color: var(--cream);
  padding: 3px 10px; border-radius: 4px;
  font-family: Georgia, serif; font-size: 11px; font-weight: 700;
  letter-spacing: 0.12em;
}
.ch-header h1 {
  font-family: Georgia, serif; font-weight: 700;
  font-size: clamp(22px, 3vw, 28px); line-height: 1.2;
  color: var(--navy); margin: 10px 0 4px;
}
[data-theme="dark"] .ch-header h1 { color: var(--gold); }
.ch-cat {
  font-size: 13px; color: var(--muted); font-style: italic;
}

.ch-box {
  margin: 14px 0; padding: 14px 18px;
  background: var(--surface-alt); border-radius: 6px;
  border-left: 4px solid var(--gold);
}
.box-label {
  display: block; font-family: Georgia, serif;
  font-size: 11px; font-weight: 700; letter-spacing: 0.14em;
  text-transform: uppercase; color: var(--coral); margin-bottom: 6px;
}
.ch-box p { margin: 6px 0; line-height: 1.6; }

.ch-box.big-idea { border-left-color: var(--navy); background: var(--research); }
.ch-box.big-idea .box-label { color: var(--navy); }
.ch-box.big-idea p { font-size: 17px; font-weight: 600; color: var(--navy); }
[data-theme="dark"] .ch-box.big-idea { background: rgba(15,76,92,0.20); }
[data-theme="dark"] .ch-box.big-idea p,
[data-theme="dark"] .ch-box.big-idea .box-label { color: var(--gold); }

.ch-box.simple-rule { border-left-color: var(--gold); background: rgba(247,181,56,0.15); }
.ch-box.simple-rule .box-label { color: #A57014; }
[data-theme="dark"] .ch-box.simple-rule { background: rgba(247,181,56,0.10); }
[data-theme="dark"] .ch-box.simple-rule .box-label { color: var(--gold); }

.ch-box.spanish-comparison { border-left-color: #B65C2A; background: rgba(182,92,42,0.08); }
.ch-box.spanish-comparison .box-label { color: #B65C2A; }

.ch-box.common-mistake { border-left-color: var(--coral); background: rgba(199,81,70,0.08); }

.ch-box.real-examples ul { margin: 8px 0 0 18px; line-height: 1.75; }
.ch-box.real-examples li { padding: 2px 0; }

.ch-box.practice-box ol, .ch-box.practice-box ul { margin: 10px 0 0 22px; line-height: 1.7; }
.ch-box.practice-box li { padding: 4px 0; }

.ans-details {
  margin-top: 12px; padding: 10px 14px;
  background: var(--research); border-radius: 6px;
  border: 1px dashed rgba(15,76,92,0.3);
}
.ans-details summary {
  font-family: Georgia, serif; font-weight: 700; cursor: pointer;
  color: var(--navy); font-size: 13px; letter-spacing: 0.04em;
}
[data-theme="dark"] .ans-details { background: rgba(15,76,92,0.20); }
[data-theme="dark"] .ans-details summary { color: var(--gold); }

.ch-teacher, .ch-sources {
  margin: 18px 0; padding: 12px 16px;
  background: var(--soft); border-radius: 6px;
  border-left: 3px solid var(--muted);
}
.ch-teacher summary, .ch-sources summary {
  font-family: Georgia, serif; font-weight: 700; cursor: pointer;
  color: var(--navy); font-size: 13px; letter-spacing: 0.04em;
}
[data-theme="dark"] .ch-teacher, [data-theme="dark"] .ch-sources { background: rgba(255,255,255,0.04); }
[data-theme="dark"] .ch-teacher summary, [data-theme="dark"] .ch-sources summary { color: var(--gold); }

.ch-table {
  border-collapse: collapse; width: 100%; margin: 10px 0; font-size: 14px;
}
.ch-table th, .ch-table td {
  padding: 8px 12px; text-align: left;
  border: 1px solid var(--border);
}
.ch-table th {
  background: rgba(15,76,92,0.08);
  font-family: Georgia, serif; font-weight: 700; font-size: 13px;
  color: var(--navy);
}
[data-theme="dark"] .ch-table th { background: rgba(255,255,255,0.06); color: var(--gold); }

.contrast-label {
  font-family: Georgia, serif; font-size: 12px; font-weight: 700;
  letter-spacing: 0.10em; text-transform: uppercase;
  color: var(--coral); margin: 12px 0 4px;
}

/* ===== ABOUT ===== */
.about-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 18px; margin-top: 24px;
}
.about-card {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: 8px; padding: 22px 24px;
  border-top: 4px solid var(--coral);
}
.about-card:nth-child(2) { border-top-color: var(--gold); }
.about-card:nth-child(3) { border-top-color: var(--navy); }
.card-label {
  display: block; font-family: Georgia, serif;
  font-size: 11px; font-weight: 700; letter-spacing: 0.14em;
  text-transform: uppercase; color: var(--coral); margin-bottom: 8px;
}
.about-card p { color: var(--text); font-size: 14.5px; line-height: 1.6; margin: 0 0 8px; }
.about-card.lll-card { border-top-color: var(--navy); background: var(--research); }
[data-theme="dark"] .about-card.lll-card { background: rgba(15,76,92,0.20); }
.about-card.lll-card .card-label { color: var(--navy); }
[data-theme="dark"] .about-card.lll-card .card-label { color: var(--gold); }
.lll-link-row { margin-top: 12px !important; }
.lll-link {
  display: inline-block;
  background: var(--navy); color: var(--gold);
  padding: 8px 16px; border-radius: 6px;
  text-decoration: none; font-family: Georgia, serif;
  font-weight: 700; font-size: 14px; letter-spacing: 0.02em;
  transition: background 0.15s, transform 0.15s;
}
.lll-link:hover { background: var(--coral); color: var(--cream); transform: translateY(-1px); }

/* ===== REFERENCES ===== */
.references { background: var(--surface-alt); }
.ref-list {
  list-style: none; padding: 0; margin: 0;
  counter-reset: ref;
}
.ref-list li {
  counter-increment: ref;
  background: var(--surface); border: 1px solid var(--border);
  border-left: 3px solid var(--gold);
  border-radius: 6px;
  padding: 14px 18px 14px 52px;
  margin-bottom: 10px;
  font-size: 14.5px; line-height: 1.6;
  position: relative;
  text-indent: 0;
}
.ref-list li::before {
  content: counter(ref) ".";
  position: absolute; left: 18px; top: 14px;
  font-family: Georgia, serif; font-weight: 700;
  color: var(--coral); font-size: 14.5px;
}
.ref-list li em { font-style: italic; }

/* ===== FOOTER ===== */
.site-footer {
  background: var(--navy); color: var(--cream);
  padding: 36px 0; margin-top: 48px;
}
.site-footer .brand-title { color: var(--cream); }
.site-footer .brand-subtitle { color: rgba(248,244,227,0.7); }
.footer-grid {
  display: grid; grid-template-columns: 2fr 1fr; gap: 28px; align-items: start;
}
.site-footer p { color: rgba(248,244,227,0.85); font-size: 14px; margin: 8px 0 0; }
.footer-meta { font-style: italic; color: rgba(248,244,227,0.65) !important; font-size: 12px !important; }
.footer-links {
  display: flex; flex-direction: column; gap: 6px;
}
.footer-links a { color: var(--gold); text-decoration: none; font-size: 14px; }
.footer-links a:hover { color: var(--cream); text-decoration: underline; }

/* ===== RESPONSIVE ===== */
@media (max-width: 800px) {
  .nav-shell { gap: 10px; padding: 10px 16px; }
  .nav-menu { flex: 0 0 100%; order: 3; justify-content: flex-start; gap: 14px; padding: 8px 0; border-top: 1px solid var(--border); }
  .nav-actions { order: 2; }
  .hero { padding: 40px 0 32px; }
  .reader { padding: 22px 18px 28px; }
  .footer-grid { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
  .reader-bar { gap: 8px; }
  .reader-counter { width: 100%; text-align: center; order: 3; }
  .reader-nav-btn { font-size: 12px; padding: 6px 10px; }
  .reader-close { width: 32px; height: 32px; font-size: 18px; }
}