/* =========================================
   BOOKVERSE - STAGE 1 DESIGN
   Warm light-brown / beige theme
   ========================================= */

:root {
  --bg: #f3eadf;
  --surface: #fffaf4;
  --surface-2: #eadbc9;
  --primary: #5a3e2b;
  --primary-dark: #3f2a1d;
  --text: #241b15;
  --muted: #75675c;
  --border: #d8c6b3;
  --success: #4d6b4a;
  --danger: #8b4545;
  --shadow: 0 4px 16px rgba(70, 45, 25, 0.10);
  --radius: 16px;
}

* { box-sizing: border-box; }
html { min-height: 100%; scroll-behavior: smooth; }
body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--text);
  font-family: Arial, Helvetica, sans-serif;
  line-height: 1.6;
  -webkit-text-size-adjust: 100%;
}
button, input, textarea { font: inherit; }
button { -webkit-tap-highlight-color: transparent; }

header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 18px 20px;
  display: flex;
  align-items: flex-start;
  gap: 25px;
  box-shadow: 0 2px 8px rgba(70, 45, 25, 0.06);
}
header > b {
  font-size: 26px;
  color: var(--primary-dark);
  white-space: nowrap;
  display: block;
  line-height: 1.2;
}
header nav {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 7px;
}
header nav button {
  border: none;
  background: transparent;
  color: var(--primary);
  font-size: 17px;
  font-weight: 600;
  padding: 7px 12px;
  border-radius: 9px;
  cursor: pointer;
  text-align: left;
  transition: 0.2s ease;
  min-width: 145px;
}
header nav button:hover { background: var(--surface-2); color: var(--primary-dark); transform: translateX(3px); }
header nav button:active { transform: translateX(1px); }

main#app {
  width: 100%;
  max-width: 1100px;
  margin: 0 auto;
  padding: 35px 20px 60px;
}
.hero {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 22px;
  padding: 45px 30px;
  margin-bottom: 30px;
  box-shadow: var(--shadow);
}
.hero h1 { margin-top: 0; font-size: 42px; color: var(--primary-dark); }
.hero p { font-size: 19px; color: var(--muted); }
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  margin-bottom: 20px;
  box-shadow: var(--shadow);
  overflow-wrap: anywhere;
}
.card h1, .card h2, .card h3 { color: var(--primary-dark); }
.card p { color: var(--text); }
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 20px; }
.cover {
  width: 100%;
  min-height: 180px;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 20px;
  margin-bottom: 18px;
  color: var(--primary-dark);
  font-size: 22px;
  font-weight: bold;
}
.btn {
  border: none;
  background: var(--primary);
  color: white;
  border-radius: 10px;
  padding: 12px 20px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  margin: 5px 5px 5px 0;
  transition: 0.2s ease;
  min-height: 44px;
}
.btn:hover { background: var(--primary-dark); transform: translateY(-1px); }
.btn:active { transform: translateY(0); }
.btn:disabled { opacity: 0.65; cursor: wait; transform: none; }
.input, .textarea {
  display: block;
  width: 100%;
  max-width: 700px;
  background: #fffdf9;
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 13px 14px;
  font-size: 16px;
  margin: 10px 0;
  outline: none;
}
.textarea { min-height: 140px; resize: vertical; }
.input:focus, .textarea:focus { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(90, 62, 43, 0.12); }
.muted { color: var(--muted) !important; }
h1 { color: var(--primary-dark); font-size: 34px; }
h2 { color: var(--primary-dark); }
h3 { color: var(--primary); }
a { color: var(--primary); }
a:hover { color: var(--primary-dark); }

/* =========================================
   PHASE 4 - READER
   ========================================= */
.reader-shell { width: 100%; max-width: 900px; margin: 0 auto; }
.reader-card { padding: 22px; }
.reader-header { margin-bottom: 12px; }
.reader-title { margin: 4px 0; font-size: 32px; }
.reader-chapter-title { margin: 0 0 16px; font-size: 24px; }
.chapter-content {
  white-space: pre-wrap;
  line-height: 1.9;
  font-size: 19px;
  max-height: 68vh;
  overflow-y: auto;
  overscroll-behavior: contain;
  -webkit-overflow-scrolling: touch;
  padding: 14px 8px;
  scroll-behavior: smooth;
}
.reader-controls {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  margin-top: 18px;
}
.reader-controls .btn { width: 100%; margin: 0; }
.loading-card { text-align: center; padding: 35px 20px; }
.loading-pulse {
  display: inline-block;
  width: 44px;
  height: 44px;
  border: 4px solid var(--surface-2);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: bookverse-spin 0.8s linear infinite;
}
@keyframes bookverse-spin { to { transform: rotate(360deg); } }

@media (max-width: 700px) {
  header { flex-direction: column; gap: 12px; padding: 16px; }
  header > b { font-size: 27px; }
  header nav { width: 100%; gap: 3px; }
  header nav button { width: 100%; min-width: 0; font-size: 17px; padding: 9px 12px; }
  main#app { padding: 25px 14px 50px; }
  .hero { padding: 30px 22px; }
  .hero h1 { font-size: 32px; }
  .hero p { font-size: 17px; }
  .card { padding: 20px; }
  .grid { grid-template-columns: 1fr; }
  .cover { min-height: 160px; }
  .btn { width: 100%; margin: 5px 0; }
  .reader-card { padding: 16px; }
  .reader-title { font-size: 27px; }
  .reader-chapter-title { font-size: 21px; }
  .chapter-content {
    font-size: 18px;
    line-height: 1.85;
    max-height: 70vh;
    padding: 12px 4px;
  }
  .reader-controls { grid-template-columns: 1fr; gap: 8px; }
}

@media (max-width: 400px) {
  header > b { font-size: 24px; }
  .hero h1, h1 { font-size: 28px; }
  .card { padding: 17px; }
  .chapter-content { font-size: 17px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .loading-pulse { animation: none; }
  .btn { transition: none; }
}