/* retop.app — STL simplifier for 3D printing */

:root {
  --f-sans: 'Space Grotesk', system-ui, -apple-system, sans-serif;
  --f-display: 'Archivo', system-ui, sans-serif;
  --f-mono: 'JetBrains Mono', ui-monospace, Menlo, monospace;

  --bg: #0a0b0e;
  --bg-elev: #12141a;
  --bg-sidebar: #0d0f14;
  --panel: #171a21;
  --ink: #e8eaef;
  --ink-2: #a0a6b3;
  --ink-3: #656b78;
  --ink-4: #3b414c;
  --line: rgba(255, 255, 255, 0.06);
  --line-soft: rgba(255, 255, 255, 0.03);
  --accent: #ff6b35;
  --accent-soft: rgba(255, 107, 53, 0.12);
  --success: #4ade80;

  --r-sm: 8px;
  --r-md: 12px;
  --r-lg: 18px;
  --r-pill: 999px;

  --dur: 240ms;
  --e-out: cubic-bezier(0.32, 0.72, 0, 1);
}

@media (prefers-color-scheme: light) {
  :root {
    --bg: #f7f8fa;
    --bg-elev: #ffffff;
    --bg-sidebar: #f0f2f5;
    --panel: #ffffff;
    --ink: #0a0b0e;
    --ink-2: #4a5260;
    --ink-3: #7a8291;
    --ink-4: #a9b0bc;
    --line: rgba(0, 0, 0, 0.08);
    --line-soft: rgba(0, 0, 0, 0.04);
    --accent-soft: rgba(255, 107, 53, 0.08);
  }
}

*, *::before, *::after { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  height: 100%;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--f-sans);
  font-size: 14px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  overflow: hidden;
}

a { color: inherit; text-decoration: none; }
button { font: inherit; cursor: pointer; border: none; background: none; color: inherit; padding: 0; }
code { font-family: var(--f-mono); font-feature-settings: 'tnum' 1; }
::selection { background: var(--accent); color: white; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; border-radius: 4px; }

/* ============ TOPBAR ============ */
.topbar {
  display: flex;
  align-items: center;
  gap: 32px;
  height: 56px;
  padding: 0 20px;
  background: var(--bg-elev);
  border-bottom: 1px solid var(--line);
  position: relative;
  z-index: 10;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--f-display);
  font-weight: 600;
  font-size: 16px;
  letter-spacing: -0.02em;
}
.brand-mark {
  width: 22px;
  height: 22px;
  color: var(--accent);
}
.brand em {
  font-style: normal;
  font-weight: 400;
  color: var(--ink-3);
}
.topnav {
  display: flex;
  gap: 4px;
  font-size: 13.5px;
}
.topnav a {
  padding: 7px 12px;
  color: var(--ink-2);
  border-radius: var(--r-sm);
  transition: background var(--dur) var(--e-out), color var(--dur) var(--e-out);
}
.topnav a:hover { color: var(--ink); background: var(--line-soft); }
.topnav a[aria-current="page"] { color: var(--ink); background: var(--line-soft); }
.topright {
  margin-left: auto;
}
.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 10px;
  font-family: var(--f-mono);
  font-size: 11px;
  letter-spacing: 0.04em;
  color: var(--success);
  background: rgba(74, 222, 128, 0.1);
  border: 1px solid rgba(74, 222, 128, 0.25);
  border-radius: var(--r-pill);
}
.chip::before {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--success);
}

/* ============ WORKSPACE ============ */
.workspace {
  display: grid;
  grid-template-columns: 320px 1fr;
  height: calc(100dvh - 56px);
}

/* ============ SIDEBAR ============ */
.sidebar {
  background: var(--bg-sidebar);
  border-right: 1px solid var(--line);
  overflow-y: auto;
  padding: 18px 16px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}
.panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}
.panel-title {
  font-family: var(--f-mono);
  font-size: 10.5px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-3);
  margin: 0;
  font-weight: 500;
}

/* ============ DROPZONE ============ */
.dropzone {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  padding: 32px 16px;
  border: 1.5px dashed var(--line);
  border-radius: var(--r-md);
  cursor: pointer;
  transition: all var(--dur) var(--e-out);
  text-align: center;
}
.dropzone:hover,
.dropzone.drag {
  border-color: var(--accent);
  background: var(--accent-soft);
}
.dropzone svg {
  width: 32px;
  height: 32px;
  color: var(--ink-3);
  transition: color var(--dur) var(--e-out);
}
.dropzone:hover svg,
.dropzone.drag svg {
  color: var(--accent);
}
.drop-label {
  font-size: 13.5px;
  color: var(--ink);
  font-weight: 500;
}
.drop-hint {
  font-family: var(--f-mono);
  font-size: 10.5px;
  color: var(--ink-3);
  letter-spacing: 0.04em;
}

/* ============ META ROWS ============ */
.file-meta,
.result-stats {
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.meta-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 12px;
  padding: 6px 0;
  border-bottom: 1px solid var(--line-soft);
  font-size: 12.5px;
}
.meta-row:last-child { border-bottom: none; }
.meta-row span {
  color: var(--ink-3);
  font-family: var(--f-mono);
  font-size: 10.5px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.meta-row code {
  color: var(--ink);
  font-size: 13px;
}

/* ============ SLIDER ============ */
.slider-group {
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.slider-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
}
.slider-head label {
  font-size: 12.5px;
  color: var(--ink-2);
  font-weight: 500;
}
.slider-head output {
  font-family: var(--f-mono);
  font-size: 15px;
  font-weight: 500;
  color: var(--accent);
  letter-spacing: -0.01em;
}
input[type="range"] {
  appearance: none;
  width: 100%;
  height: 4px;
  background: var(--line);
  border-radius: var(--r-pill);
  outline: none;
  cursor: pointer;
}
input[type="range"]::-webkit-slider-thumb {
  appearance: none;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--accent);
  border: 2px solid var(--bg-elev);
  box-shadow: 0 0 0 1px var(--accent);
  cursor: grab;
}
input[type="range"]::-webkit-slider-thumb:active { cursor: grabbing; transform: scale(1.1); }
input[type="range"]::-moz-range-thumb {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--accent);
  border: 2px solid var(--bg-elev);
  cursor: grab;
}
.slider-hint {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--f-mono);
  font-size: 11px;
  color: var(--ink-3);
}
.slider-hint .arrow { color: var(--ink-4); }

/* ============ PRESETS ============ */
.preset-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 6px;
}
.preset {
  padding: 7px 0;
  font-family: var(--f-mono);
  font-size: 11.5px;
  letter-spacing: 0.03em;
  color: var(--ink-2);
  background: transparent;
  border: 1px solid var(--line);
  border-radius: var(--r-sm);
  transition: all var(--dur) var(--e-out);
}
.preset:hover {
  color: var(--ink);
  border-color: var(--ink-4);
  background: var(--line-soft);
}
.preset:active { transform: scale(0.97); }

/* ============ BUTTONS ============ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 10px 16px;
  font-family: var(--f-sans);
  font-size: 13.5px;
  font-weight: 500;
  letter-spacing: -0.005em;
  border-radius: var(--r-sm);
  transition: all var(--dur) var(--e-out);
  cursor: pointer;
}
.btn svg { width: 15px; height: 15px; }
.btn-primary {
  background: var(--accent);
  color: white;
}
.btn-primary:hover { filter: brightness(1.1); }
.btn-primary:active { transform: translateY(1px); }
.btn-primary:disabled {
  background: var(--line);
  color: var(--ink-3);
  cursor: not-allowed;
}
.btn-ghost {
  background: var(--line-soft);
  color: var(--ink);
  border: 1px solid var(--line);
}
.btn-ghost:hover { background: var(--line); }

/* ============ TOGGLE GROUP ============ */
.toggle-group {
  display: inline-flex;
  background: var(--line-soft);
  border: 1px solid var(--line);
  border-radius: var(--r-sm);
  padding: 2px;
  width: 100%;
}
.toggle {
  flex: 1;
  padding: 6px 0;
  font-size: 12px;
  color: var(--ink-3);
  border-radius: 6px;
  transition: all var(--dur) var(--e-out);
}
.toggle:hover { color: var(--ink-2); }
.toggle.active {
  background: var(--panel);
  color: var(--ink);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.15);
}

/* ============ SIDE FOOTER ============ */
.side-footer {
  margin-top: auto;
  padding-top: 16px;
  font-family: var(--f-mono);
  font-size: 10.5px;
  letter-spacing: 0.06em;
  color: var(--ink-3);
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}
.side-footer a:hover { color: var(--ink); }

/* ============ VIEWPORT ============ */
.viewport-wrap {
  position: relative;
  background:
    radial-gradient(ellipse at center, var(--bg-elev) 0%, var(--bg) 100%);
  overflow: hidden;
}
#viewport {
  display: block;
  width: 100%;
  height: 100%;
}
.viewport-overlay {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  pointer-events: none;
  text-align: center;
  padding: 40px;
}
.viewport-overlay.hidden {
  display: none;
}
.viewport-overlay svg {
  width: 80px;
  height: 80px;
  color: var(--ink-4);
  margin-bottom: 20px;
}
.viewport-overlay h1 {
  font-family: var(--f-display);
  font-weight: 500;
  font-size: clamp(28px, 3.5vw, 44px);
  letter-spacing: -0.025em;
  line-height: 1.1;
  margin: 0 0 12px;
}
.viewport-overlay h1 em {
  color: var(--accent);
  font-style: normal;
}
.viewport-overlay p {
  color: var(--ink-2);
  font-size: 15px;
  max-width: 440px;
  margin: 0 0 24px;
}
.features {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-family: var(--f-mono);
  font-size: 11.5px;
  color: var(--ink-3);
  letter-spacing: 0.02em;
}
.features li::before {
  content: '→ ';
  color: var(--accent);
}

/* ============ HUD ============ */
.viewport-hud {
  position: absolute;
  bottom: 16px;
  left: 16px;
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 10px 14px;
  background: rgba(10, 11, 14, 0.75);
  backdrop-filter: blur(10px);
  border: 1px solid var(--line);
  border-radius: var(--r-sm);
  font-family: var(--f-mono);
  font-size: 11px;
  pointer-events: none;
}
.viewport-hud .hud-label {
  color: var(--ink-3);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-size: 9.5px;
  margin-right: 8px;
}
.viewport-hud code { color: var(--ink); }

/* ============ TOAST ============ */
.toast {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translate(-50%, 30px);
  background: var(--panel);
  border: 1px solid var(--line);
  color: var(--ink);
  padding: 10px 18px;
  border-radius: var(--r-pill);
  font-size: 13px;
  z-index: 100;
  opacity: 0;
  pointer-events: none;
  transition: all var(--dur) var(--e-out);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.4);
}
.toast.show { opacity: 1; transform: translate(-50%, 0); }
.toast.err { border-color: #f87171; color: #fca5a5; }
.toast.ok { border-color: var(--success); color: var(--success); }

/* ============ ARTICLE / ABOUT ============ */
.article-wrap {
  overflow-y: auto;
  height: calc(100dvh - 56px);
}
.article {
  max-width: 720px;
  margin: 0 auto;
  padding: 60px 24px 100px;
}
.article h1 {
  font-family: var(--f-display);
  font-weight: 500;
  font-size: clamp(36px, 5vw, 56px);
  line-height: 1.05;
  letter-spacing: -0.03em;
  margin: 0 0 20px;
}
.article h1 em { color: var(--accent); font-style: normal; }
.article .lead {
  font-size: 18px;
  color: var(--ink-2);
  line-height: 1.55;
  margin: 0 0 48px;
  max-width: 56ch;
}
.article h2 {
  font-family: var(--f-display);
  font-weight: 500;
  font-size: 22px;
  letter-spacing: -0.02em;
  margin: 40px 0 12px;
}
.article p {
  color: var(--ink-2);
  margin: 0 0 16px;
  line-height: 1.65;
}
.article code {
  background: var(--panel);
  border: 1px solid var(--line);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 12.5px;
}
.article ul {
  padding-left: 20px;
  color: var(--ink-2);
}
.article li { margin-bottom: 8px; }

/* ============ MOBILE ============ */
@media (max-width: 880px) {
  .workspace {
    grid-template-columns: 1fr;
    grid-template-rows: auto 1fr;
    height: calc(100dvh - 56px);
  }
  .sidebar {
    border-right: none;
    border-bottom: 1px solid var(--line);
    max-height: 55vh;
  }
  .topnav { display: none; }
  .brand-name { font-size: 15px; }
  .viewport-overlay h1 { font-size: 28px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}