:root {
  --bg: #f3f5f7;
  --ink: #1a1d21;
  --muted: #6b7280;
  --accent: #1f6feb;
  --card: #ffffff;
  --line: #e5e7eb;
  --danger: #c62828;
  --ok: #2e7d32;
  --nav-h: 64px;
  --font-display: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-body: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
}

* { box-sizing: border-box; }
html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-body);
  min-height: 100%;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; }
ul { list-style: none; margin: 0; padding: 0; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-height: var(--nav-h);
  padding: 0.75rem 1.5rem;
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.04em;
}
.brand img, .brand-logo {
  height: 36px;
  width: 36px;
  object-fit: contain;
  border-radius: 8px;
  background: transparent;
  display: inline-block;
  vertical-align: middle;
}
.brand-logo-lg {
  height: 72px;
  width: 72px;
  border-radius: 16px;
}
.nav-links {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}
.nav-links a, .nav-links button.linkish {
  font-size: 0.85rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--muted);
  background: none;
  border: 0;
  cursor: pointer;
  padding: 0;
}
.nav-links a:hover, .nav-links a.active { color: var(--ink); }

.dropdown { position: relative; }
.dropdown-panel {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  min-width: 180px;
  background: var(--card);
  border: 1px solid var(--line);
  box-shadow: 0 8px 24px rgba(0,0,0,0.08);
  padding: 0.5rem 0;
  z-index: 60;
}
.dropdown:hover .dropdown-panel,
.dropdown:focus-within .dropdown-panel { display: block; }
.dropdown-panel a {
  display: block;
  padding: 0.45rem 1rem;
  font-size: 0.8rem;
}

.search-form {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}
.search-form input {
  border: 1px solid var(--line);
  background: #fff;
  padding: 0.45rem 0.7rem;
  min-width: 160px;
  font-size: 0.85rem;
}
.search-form button, .btn {
  border: 0;
  background: var(--accent);
  color: #fff;
  padding: 0.5rem 0.9rem;
  font-size: 0.85rem;
  cursor: pointer;
  letter-spacing: 0.04em;
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  vertical-align: middle;
  text-decoration: none;
  line-height: 1.2;
}
.btn.secondary { background: #374151; }
.btn.ghost {
  background: transparent;
  color: var(--ink);
  border: 1px solid var(--line);
}
.btn.danger { background: var(--danger); }
.btn:disabled { opacity: 0.55; cursor: not-allowed; }

/*
 * Whole-button 3D flip (cube rotateX):
 * parent = perspective shell; inner = rigid body; faces = front + bottom.
 */
.btn-flip {
  --flip-h: 2.45em;
  --flip-pad-x: 0.9rem;
  --btn-bg: var(--accent);
  --btn-fg: #fff;
  --btn-border: transparent;
  height: var(--flip-h);
  padding: 0 !important;
  border: 0 !important;
  background: transparent !important;
  color: var(--btn-fg);
  overflow: visible;
  perspective: 800px;
  perspective-origin: 50% 50%;
  transform-style: preserve-3d;
}
.btn-flip.secondary { --btn-bg: #374151; --btn-fg: #fff; }
.btn-flip.danger { --btn-bg: var(--danger); --btn-fg: #fff; }
.btn-flip.ghost {
  --btn-bg: #fff;
  --btn-fg: var(--ink);
  --btn-border: var(--line);
}
.search-form button.btn-flip {
  --btn-bg: var(--accent);
  --btn-fg: #fff;
}
.viewer-toolbar .btn.btn-flip {
  --btn-bg: #fff;
  --btn-fg: #111;
  --btn-border: transparent;
}
.viewer-toolbar .btn.btn-flip.secondary {
  --btn-bg: #374151;
  --btn-fg: #fff;
}
.viewer-toolbar .btn.btn-flip.ghost {
  --btn-bg: rgba(255,255,255,0.12);
  --btn-fg: #fff;
  --btn-border: rgba(255,255,255,0.35);
}

.btn-flip-inner {
  position: relative;
  display: block;
  width: 100%;
  height: 100%;
  transform-style: preserve-3d;
  transition: transform 0.48s cubic-bezier(0.4, 0.1, 0.2, 1);
  will-change: transform;
}
.btn-flip:hover:not(:disabled) .btn-flip-inner,
.btn-flip:focus-visible:not(:disabled) .btn-flip-inner {
  transform: rotateX(90deg);
}

.btn-flip-face {
  display: flex;
  align-items: center;
  justify-content: center;
  box-sizing: border-box;
  height: 100%;
  padding: 0 var(--flip-pad-x);
  background: var(--btn-bg);
  color: var(--btn-fg);
  border: 1px solid var(--btn-border);
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
  box-shadow: 0 1px 0 rgba(0,0,0,0.06);
}
.btn-flip-front {
  position: relative;
  transform: translateZ(calc(var(--flip-h) / 2));
}
.btn-flip-back {
  position: absolute;
  inset: 0;
  transform: rotateX(-90deg) translateZ(calc(var(--flip-h) / 2));
}

@media (prefers-reduced-motion: reduce) {
  .btn-flip-inner { transition: none; }
  .btn-flip:hover:not(:disabled) .btn-flip-inner,
  .btn-flip:focus-visible:not(:disabled) .btn-flip-inner {
    transform: none;
  }
}

.user-chip {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.user-chip img {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  object-fit: cover;
  background: #ddd;
}

.page {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem 1.5rem 4rem;
}
.hero-block {
  margin-bottom: 2rem;
}
.hero-block h1 {
  margin: 0 0 0.35rem;
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.hero-block p {
  margin: 0;
  color: var(--muted);
}

.model-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 1.25rem;
}
.product_box, .model-card {
  background: var(--card);
  border: 1px solid var(--line);
  overflow: hidden;
  display: flex;
  flex-direction: column;
}
.product_show, .model-thumb {
  aspect-ratio: 4 / 3;
  background: #e8ecef center/cover no-repeat;
  display: block;
}
.product_description, .model-meta {
  padding: 0.85rem 1rem 1rem;
  display: grid;
  gap: 0.35rem;
}
.product_title, .model-title {
  font-weight: 600;
  margin: 0;
  font-size: 0.95rem;
}
.model-stats {
  display: flex;
  gap: 0.85rem;
  color: var(--muted);
  font-size: 0.8rem;
}
.model-actions {
  display: flex;
  gap: 0.4rem;
  flex-wrap: wrap;
}
.model-actions button, .model-actions a {
  font-size: 0.75rem;
  padding: 0.3rem 0.55rem;
}
.model-actions .btn-flip {
  --flip-h: 1.95em;
  --flip-pad-x: 0.55rem;
  font-size: 0.75rem;
}

.auth-shell {
  min-height: calc(100vh - var(--nav-h));
  display: grid;
  place-items: center;
  padding: 2rem 1rem;
  background:
    radial-gradient(circle at 20% 20%, rgba(31,111,235,0.12), transparent 40%),
    radial-gradient(circle at 80% 0%, rgba(0,0,0,0.05), transparent 35%),
    var(--bg);
}
.auth-card, .form-card {
  width: min(420px, 100%);
  background: var(--card);
  border: 1px solid var(--line);
  padding: 2rem 1.5rem;
}
.auth-card h1, .form-card h1 {
  margin: 0 0 1.25rem;
  font-size: 1.25rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  text-align: center;
}
.form-row {
  display: grid;
  gap: 0.35rem;
  margin-bottom: 0.9rem;
}
.form-row label {
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--muted);
}
.form-row input, .form-row textarea, .form-row select {
  width: 100%;
  border: 1px solid var(--line);
  padding: 0.65rem 0.75rem;
  font: inherit;
  background: #fff;
}
.form-row textarea { min-height: 100px; resize: vertical; }
.form-actions { display: flex; gap: 0.6rem; margin-top: 1rem; }
.flash {
  padding: 0.7rem 0.9rem;
  margin-bottom: 1rem;
  border: 1px solid var(--line);
  background: #fff;
  font-size: 0.9rem;
}
.flash.error { border-color: #ffcdd2; color: var(--danger); background: #ffebee; }
.flash.success, .flash.ok { border-color: #c8e6c9; color: var(--ok); background: #e8f5e9; }
.flash.warning { border-color: #ffe0b2; color: #e65100; background: #fff3e0; }

.profile-head {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: 1.25rem;
  align-items: center;
  margin-bottom: 2rem;
}
.profile-head .avatar_big img, .profile-head img {
  width: 120px;
  height: 120px;
  border-radius: 50%;
  object-fit: cover;
  background: #ddd;
}
.profile-stats {
  display: flex;
  gap: 1.25rem;
  color: var(--muted);
  font-size: 0.9rem;
  margin-top: 0.5rem;
}

.show-page-full, body.show-page-full {
  min-height: 100%;
  overflow-y: auto;
  background: #111;
}
.show-layout {
  min-height: calc(100vh - var(--nav-h));
}
#webGLContainer, #webGLContainerCanvas {
  width: 100%;
  height: calc(100vh - var(--nav-h));
  display: block;
}
.viewer-toolbar {
  position: relative;
  margin: -3.5rem 1rem 1rem;
  z-index: 20;
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  align-items: center;
  background: rgba(0,0,0,0.55);
  color: #fff;
  padding: 0.65rem 0.85rem;
  max-width: calc(100% - 2rem);
}
.viewer-toolbar .btn { background: #fff; color: #111; }
.viewer-toolbar .btn-flip { --flip-h: 2.25em; }
.viewer-toolbar .meta { font-size: 0.85rem; opacity: 0.9; }
.viewer-toolbar .meta a { color: #9ecbff; }
.comments-panel {
  background: #1a1a1a;
  color: #ccc;
  padding: 1.25rem 1.5rem 2.5rem;
}
.comments-panel h3 {
  margin: 0 0 0.75rem;
  color: #fff;
  font-size: 1rem;
}
.comment-item {
  background: #2a2a2a;
  padding: 0.65rem 0.85rem;
  margin: 0 0 0.5rem;
  border-radius: 4px;
  font-size: 0.85rem;
}
.comment-item p { margin: 0.35rem 0 0; }
.comment-head {
  display: flex;
  gap: 0.65rem;
  align-items: center;
  flex-wrap: wrap;
}
.comment-head .muted, .comments-panel .muted { color: #888; font-size: 0.75rem; }
.comment-form {
  display: flex;
  gap: 0.5rem;
  margin-top: 0.85rem;
  align-items: flex-start;
}
.comment-form textarea {
  flex: 1;
  padding: 0.5rem;
  border: 0;
  border-radius: 4px;
  resize: vertical;
  min-height: 2.5rem;
  font: inherit;
}
.gallery-filters {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin: 0 0 1.25rem;
  align-items: center;
}
.gallery-filters input[type="search"],
.gallery-filters select {
  padding: 0.45rem 0.65rem;
  border: 1px solid var(--line);
  background: #fff;
  font: inherit;
  min-width: 10rem;
}
.pagination {
  display: flex;
  gap: 0.75rem;
  align-items: center;
  justify-content: center;
  margin: 1.75rem 0 0.5rem;
}
.pagination-meta { color: var(--muted); font-size: 0.85rem; }

.edit-layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 1.25rem;
}
@media (max-width: 860px) {
  .edit-layout { grid-template-columns: 1fr; }
  .profile-head { grid-template-columns: 1fr; justify-items: start; }
  .site-header { flex-wrap: wrap; }
}

.footer {
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.8rem;
  text-align: center;
}
.empty-state {
  padding: 3rem 1rem;
  text-align: center;
  color: var(--muted);
  border: 1px dashed var(--line);
  background: rgba(255,255,255,0.5);
}
.pop-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.45);
  display: none;
  place-items: center;
  z-index: 200;
  padding: 1rem;
}
.pop-overlay.open { display: grid; }
.pop-panel {
  width: min(420px, 100%);
  background: #fff;
  padding: 1.35rem 1.4rem 1.2rem;
  border: 1px solid var(--line);
  box-shadow: 0 16px 40px rgba(0,0,0,0.18);
}
.pop-title {
  margin: 0 0 0.5rem;
  font-size: 1rem;
  letter-spacing: 0.04em;
}
.pop-message {
  margin: 0;
  color: var(--ink);
  font-size: 0.95rem;
  line-height: 1.5;
  white-space: pre-wrap;
}
.pop-prompt { margin-top: 0.85rem; }
.pop-input {
  width: 100%;
  border: 1px solid var(--line);
  padding: 0.65rem 0.75rem;
  font: inherit;
  background: #fff;
}
.pop-actions {
  display: flex;
  justify-content: flex-end;
  gap: 0.55rem;
  margin-top: 1.15rem;
}
.lang-toggle {
  font-size: 0.8rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--muted);
  background: none;
  border: 1px solid var(--line);
  cursor: pointer;
  padding: 0.25rem 0.55rem;
}
.lang-toggle:hover { color: var(--ink); border-color: #c5cad1; }
.help-content {
  max-width: 720px;
  line-height: 1.7;
  color: #333;
}
.help-content h2 { margin-top: 2rem; font-size: 1.1rem; letter-spacing: 0.05em; }