/* ── Variables ── */
:root {
  --ink: #1a1612;
  --paper: #f5f0e8;
  --cream: #e8e4dd;
  --dust: #c8c2b8;
  --fog: #9a948c;
  --accent: #8b5e3c;
  --accent-light: #c49a6c;
  --panel-bg: rgba(26, 22, 18, 0.92);
  --panel-border: rgba(255,255,255,0.06);
  --radius: 6px;
  --font-serif: 'Cormorant Garamond', Georgia, serif;
  --font-mono: 'DM Mono', monospace;
}

/* ── Reset ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html, body { width: 100%; height: 100%; overflow: hidden; background: #1a1612; }
body { font-family: var(--font-mono); font-size: 12px; color: var(--paper); }

/* ── Screens ── */
.screen {
  position: fixed; inset: 0;
  display: none; opacity: 0;
  transition: opacity 0.5s ease;
}
.screen.active { display: flex; opacity: 1; }
.screen.fade-in { opacity: 1; }

/* ── Upload Screen ── */
#upload-screen {
  align-items: center; justify-content: center;
  background: #f5f0e8;
  color: var(--ink);
}

.upload-bg {
  position: absolute; inset: 0; overflow: hidden;
}
.upload-grain {
  position: absolute; inset: 0;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)' opacity='0.04'/%3E%3C/svg%3E");
  opacity: 0.5;
}
.upload-lines {
  position: absolute; inset: 0;
  background-image: repeating-linear-gradient(
    0deg,
    transparent,
    transparent 39px,
    rgba(26,22,18,0.06) 39px,
    rgba(26,22,18,0.06) 40px
  );
}

.upload-content {
  position: relative; z-index: 1;
  display: flex; flex-direction: column;
  align-items: center; gap: 48px;
  padding: 40px;
}

.brand { text-align: center; }
.brand-mark { font-size: 32px; color: var(--accent); letter-spacing: 0; }
.brand h1 {
  font-family: var(--font-serif);
  font-size: 52px; font-weight: 300;
  color: var(--ink); letter-spacing: -1px;
  line-height: 1; margin-top: 8px;
}
.brand h1 em { font-style: italic; color: var(--accent); font-weight: 300; }
.brand-sub {
  font-family: var(--font-mono); font-size: 11px;
  color: var(--fog); letter-spacing: 2px; text-transform: uppercase;
  margin-top: 12px;
}

.drop-zone {
  width: 480px; max-width: 90vw;
  border: 1.5px dashed rgba(26,22,18,0.2);
  border-radius: 4px; cursor: pointer;
  transition: border-color 0.2s, background 0.2s;
  background: rgba(26,22,18,0.02);
}
.drop-zone:hover, .drop-zone.over {
  border-color: var(--accent);
  background: rgba(139,94,60,0.05);
}
.drop-inner {
  padding: 56px 40px;
  display: flex; flex-direction: column;
  align-items: center; gap: 12px;
}
.drop-icon { width: 48px; height: 48px; color: var(--fog); }
.drop-icon svg { width: 100%; height: 100%; }
.drop-text { font-family: var(--font-serif); font-size: 22px; font-weight: 400; color: var(--ink); }
.drop-sub { font-size: 11px; color: var(--fog); }
.drop-btn {
  margin-top: 8px;
  padding: 10px 28px;
  border: 1.5px solid var(--ink);
  border-radius: 2px;
  font-family: var(--font-mono); font-size: 11px;
  letter-spacing: 1.5px; text-transform: uppercase;
  color: var(--ink); cursor: pointer;
  transition: all 0.15s;
  background: transparent;
}
.drop-btn:hover { background: var(--ink); color: var(--paper); }
#file-input { display: none; }

.upload-specs {
  display: flex; gap: 12px;
  font-size: 10px; color: var(--fog);
  letter-spacing: 1px; text-transform: uppercase;
}

/* ── Loading Screen ── */
#loading-screen {
  align-items: center; justify-content: center;
  background: #1a1612; flex-direction: column;
}
.loading-content { display: flex; flex-direction: column; align-items: center; gap: 32px; }

.loading-book {
  position: relative; width: 80px; height: 80px;
  display: flex; align-items: center; justify-content: center;
}
.loading-page {
  position: absolute;
  width: 50px; height: 65px;
  background: var(--paper);
  border-radius: 1px;
  transform-origin: left center;
  animation: pageFlip 1.5s ease-in-out infinite;
}
.p1 { animation-delay: 0s; z-index: 3; }
.p2 { animation-delay: 0.3s; z-index: 2; left: 3px; background: #e8e4dd; }
.p3 { animation-delay: 0.6s; z-index: 1; left: 6px; background: #ddd9d0; }
@keyframes pageFlip {
  0%, 70%, 100% { transform: rotateY(0deg); }
  35% { transform: rotateY(-140deg); }
}

.loading-label {
  font-size: 11px; letter-spacing: 2px; text-transform: uppercase;
  color: var(--fog); font-family: var(--font-mono);
}
.loading-bar {
  width: 240px; height: 1px;
  background: rgba(255,255,255,0.1);
}
.loading-fill {
  height: 100%; width: 0%;
  background: var(--accent-light);
  transition: width 0.3s ease;
}

/* ── Viewer Screen ── */
#viewer-screen { display: none; background: #1a1612; }
#viewer-screen.active { display: block; }
#gl-canvas { display: block; width: 100%; height: 100%; }

/* ── HUD Top ── */
.hud-top {
  position: fixed; top: 0; left: 0; right: 0;
  height: 52px;
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 20px;
  background: linear-gradient(to bottom, rgba(26,22,18,0.7) 0%, transparent 100%);
  z-index: 100;
  pointer-events: none;
}
.hud-top > * { pointer-events: auto; }

.hud-brand {
  display: flex; align-items: center; gap: 8px;
  background: none; border: none; cursor: pointer;
  color: var(--paper); font-family: var(--font-mono);
  font-size: 11px; letter-spacing: 1px;
  opacity: 0.7; transition: opacity 0.15s;
}
.hud-brand:hover { opacity: 1; }
.brand-mark-sm { font-size: 14px; color: var(--accent-light); }

.hud-title {
  font-family: var(--font-serif); font-size: 15px;
  font-weight: 300; font-style: italic;
  color: rgba(245,240,232,0.6);
  max-width: 40%; overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
}

.hud-actions { display: flex; gap: 8px; }
.hud-btn {
  display: flex; align-items: center; gap: 6px;
  padding: 7px 14px;
  background: rgba(26,22,18,0.7); border: 1px solid var(--panel-border);
  border-radius: var(--radius);
  color: var(--paper); font-family: var(--font-mono);
  font-size: 11px; cursor: pointer; letter-spacing: 0.5px;
  transition: all 0.15s;
  backdrop-filter: blur(10px);
}
.hud-btn svg { width: 15px; height: 15px; }
.hud-btn:hover { background: rgba(139,94,60,0.3); border-color: var(--accent); }

/* ── Panel Izquierdo ── */
.panel-left {
  position: fixed; top: 0; left: 0; bottom: 0;
  width: 220px;
  background: var(--panel-bg);
  border-right: 1px solid var(--panel-border);
  backdrop-filter: blur(20px);
  overflow-y: auto; overflow-x: hidden;
  z-index: 90;
  padding-top: 60px;
  scrollbar-width: thin; scrollbar-color: rgba(255,255,255,0.1) transparent;
}
.panel-left::-webkit-scrollbar { width: 3px; }
.panel-left::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.1); border-radius: 2px; }

.panel-section {
  padding: 20px 16px;
  border-bottom: 1px solid var(--panel-border);
}
.panel-title {
  font-size: 9px; letter-spacing: 2.5px; text-transform: uppercase;
  color: var(--fog); margin-bottom: 16px; font-weight: 400;
}

.ctrl-row {
  display: flex; align-items: center; justify-content: space-between;
  margin-bottom: 12px; gap: 8px;
}
.ctrl-row label {
  font-size: 11px; color: rgba(245,240,232,0.6);
  white-space: nowrap; min-width: 70px;
}

/* Slider */
.slider {
  -webkit-appearance: none; appearance: none;
  flex: 1; height: 2px;
  background: rgba(255,255,255,0.1);
  border-radius: 1px; outline: none; cursor: pointer;
}
.slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 12px; height: 12px;
  background: var(--accent-light);
  border-radius: 50%; cursor: pointer;
  box-shadow: 0 0 8px rgba(196,154,108,0.4);
}
.slider::-moz-range-thumb {
  width: 12px; height: 12px;
  background: var(--accent-light);
  border-radius: 50%; cursor: pointer; border: none;
}

/* Color picker */
.color-row {
  display: flex; align-items: center; gap: 8px;
  flex: 1; justify-content: flex-end;
}
input[type="color"] {
  width: 24px; height: 24px;
  border: 1px solid rgba(255,255,255,0.15);
  border-radius: 3px; cursor: pointer; padding: 1px;
  background: transparent;
}
input[type="color"]::-webkit-color-swatch-wrapper { padding: 0; }
input[type="color"]::-webkit-color-swatch { border: none; border-radius: 2px; }
.color-row span {
  font-size: 10px; color: var(--fog);
  font-family: var(--font-mono); letter-spacing: 0.5px;
}

/* Select */
.select {
  flex: 1;
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: var(--radius);
  color: var(--paper); font-family: var(--font-mono);
  font-size: 11px; padding: 5px 8px;
  outline: none; cursor: pointer;
}
.select:focus { border-color: var(--accent); }

/* Page nav */
.page-nav {
  display: flex; align-items: center; gap: 8px;
}
.page-nav button {
  width: 22px; height: 22px;
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: 3px; color: var(--paper);
  font-size: 14px; cursor: pointer; line-height: 1;
  transition: all 0.15s; display: flex; align-items: center; justify-content: center;
}
.page-nav button:hover { background: var(--accent); border-color: var(--accent); }
#page-indicator { font-size: 10px; color: var(--fog); white-space: nowrap; }

/* Camera presets */
.preset-grid {
  display: grid; grid-template-columns: 1fr 1fr 1fr;
  gap: 6px;
}
.preset-btn {
  padding: 7px 4px;
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(255,255,255,0.08);
  border-radius: var(--radius);
  color: rgba(245,240,232,0.7);
  font-family: var(--font-mono); font-size: 10px;
  cursor: pointer; letter-spacing: 0.3px;
  transition: all 0.15s;
}
.preset-btn:hover {
  background: rgba(139,94,60,0.25);
  border-color: var(--accent);
  color: var(--paper);
}
.preset-btn.active {
  background: rgba(139,94,60,0.35);
  border-color: var(--accent-light);
  color: var(--accent-light);
}

/* ── Hint bar ── */
.hint-bar {
  position: fixed; bottom: 24px; left: 50%; transform: translateX(-50%);
  display: flex; gap: 24px;
  background: rgba(26,22,18,0.75);
  backdrop-filter: blur(12px);
  border: 1px solid var(--panel-border);
  border-radius: 40px;
  padding: 9px 24px;
  z-index: 90;
  transition: opacity 0.5s;
}
.hint-bar span { font-size: 10px; color: var(--fog); display: flex; align-items: center; gap: 6px; }
kbd {
  display: inline-block;
  padding: 2px 6px;
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.12);
  border-radius: 3px;
  font-family: var(--font-mono); font-size: 9px;
  color: rgba(245,240,232,0.7);
}
.hint-bar.hidden { opacity: 0; pointer-events: none; }

/* ── Toast ── */
.toast {
  position: fixed; bottom: 80px; left: 50%; transform: translateX(-50%);
  background: rgba(26,22,18,0.95);
  border: 1px solid var(--accent);
  border-radius: 40px;
  padding: 10px 24px;
  font-size: 11px; color: var(--paper);
  letter-spacing: 0.5px;
  z-index: 1000;
  opacity: 0; pointer-events: none;
  transition: opacity 0.3s;
}
.toast.show { opacity: 1; }

/* ── Responsive ── */
@media (max-width: 680px) {
  .panel-left { width: 180px; }
  .drop-zone { width: 90vw; }
  .brand h1 { font-size: 38px; }
  .hint-bar { display: none; }
}

/* ── Extras v3 ── */

/* slider value label */
.slider-val {
  font-size: 10px; color: var(--fog);
  min-width: 28px; text-align: right;
  font-family: var(--font-mono);
}

/* full-width preset button */
.preset-btn.full-width {
  grid-column: span 3;
  width: 100%;
  padding: 8px;
  text-align: center;
}

/* Cover upload */
.cover-drop {
  cursor: pointer;
  border: 1px dashed rgba(255,255,255,0.12);
  border-radius: 4px;
  overflow: hidden;
  transition: border-color .2s;
  margin-bottom: 2px;
}
.cover-drop:hover { border-color: var(--accent); }

.cover-preview {
  width: 100%;
  height: 110px;
  background: rgba(255,255,255,0.04);
  background-size: cover;
  background-position: center;
  display: flex; align-items: center; justify-content: center;
  position: relative;
  transition: background .3s;
}
.cover-preview.has-img .cover-placeholder { display: none; }

.cover-placeholder {
  display: flex; flex-direction: column;
  align-items: center; gap: 6px;
  color: var(--fog);
  font-size: 10px; letter-spacing: 0.5px;
  pointer-events: none;
}

.cover-label {
  display: block;
  padding: 6px 10px;
  font-size: 10px; letter-spacing: 0.8px; text-transform: uppercase;
  color: rgba(245,240,232,0.45);
  text-align: center;
  border-top: 1px solid rgba(255,255,255,0.06);
  cursor: pointer;
  transition: color .15s, background .15s;
}
.cover-drop:hover .cover-label { color: var(--accent-light); background: rgba(139,94,60,0.1); }

/* Disable buttons */
.page-nav button:disabled {
  opacity: 0.25;
  cursor: default;
  pointer-events: none;
}