:root {
  --paper: #ece4cf;
  --ink: #2b2b2b;
  --bar: #262422;
  --accent: #b3502b;
  --header-h: 64px;
  --footer-h: 40px;
  --icon-w: 32px;
  --controls-h: 48px;
  --chrome-v: calc(var(--header-h) + var(--footer-h) + 48px + 16px + var(--controls-h));
}

* {
  box-sizing: border-box;
}

html, body {
  height: 100%;
}

body {
  margin: 0;
  background-color: var(--paper);
  background-image:
    radial-gradient(circle at 1px 1px, rgba(0,0,0,0.05) 1px, transparent 0);
  background-size: 18px 18px;
  color: var(--ink);
}

/* ---------- Header ---------- */

header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-h);
  display: grid;
  grid-template-columns: var(--icon-w) 1fr var(--icon-w);
  align-items: center;
  column-gap: 12px;
  padding: 0 12px;
  background-color: var(--bar);
  border-bottom: 3px solid var(--accent);
  cursor: pointer;
  z-index: 20;
  transition: background-color 0.2s ease;
}

header:hover {
  background-color: #322f2c;
}

h1 {
  grid-column: 2;
  font-family: 'Special Elite', cursive;
  font-size: clamp(16px, 3vw, 26px);
  text-align: center;
  color: #f4ede0;
  margin: 0;
  letter-spacing: 0.5px;
}

.iconBtn {
  grid-column: 1;
  width: var(--icon-w);
  height: var(--icon-w);
  padding: 6px;
  border: none;
  border-radius: 50%;
  background: rgba(244, 237, 224, 0.12);
  color: #f4ede0;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background-color 0.2s ease, transform 0.2s ease;
}

.iconBtn:hover {
  background-color: var(--accent);
  transform: rotate(-8deg) scale(1.08);
}

.iconBtn svg {
  width: 100%;
  height: 100%;
}

@media (max-width: 480px) {
  :root {
    --icon-w: 26px;
    --controls-h: 44px;
  }
}

/* ---------- Main stage ---------- */

main {
  min-height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  padding-top: calc(var(--header-h) + 24px);
  padding-bottom: calc(var(--footer-h) + 24px);
}

.stage {
  position: relative;
  width: 100%;
  max-width: 640px;
  padding: 0 16px;
}

.frame {
  position: relative;
  width: min(608px, 100%, calc(100vh - var(--chrome-v)));
  margin: 0 auto;
  aspect-ratio: 1 / 1;
  background: #fff;
  padding: 14px;
  border-radius: 4px;
  box-shadow:
    0 2px 4px rgba(0,0,0,0.15),
    0 10px 30px rgba(0,0,0,0.25);
}

.frame img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: contain;
  transition: opacity 0.15s ease;
}

.frame img.is-changing {
  opacity: 0;
}

/* ---------- Nav click zones (invisible, full-height) ---------- */

.navZone {
  position: fixed;
  top: 0;
  bottom: 0;
  width: 12%;
  min-width: 40px;
  max-width: 120px;
  z-index: 10;
  cursor: pointer;
  background: transparent;
}

.navZone--left {
  left: 0;
}

.navZone--right {
  right: 0;
}

/* ---------- Controls (under the strip: prev / random / next) ---------- */

.controls {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  width: min(608px, 100%, calc(100vh - var(--chrome-v)));
  margin: 16px auto 0;
}

.ctrlBtn {
  flex: 0 0 auto;
  border: none;
  border-radius: 50%;
  background: rgba(38, 36, 34, 0.85);
  color: #fff;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background-color 0.2s ease, transform 0.2s ease;
}

.ctrlBtn:hover {
  background-color: var(--accent);
  transform: scale(1.08);
}

.ctrlBtn--arrow {
  width: var(--controls-h);
  height: var(--controls-h);
  padding: calc(var(--controls-h) * 0.22);
}

.ctrlBtn--arrow img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  filter: brightness(0) invert(1);
}

.ctrlBtn--random {
  width: calc(var(--controls-h) * 0.83);
  height: calc(var(--controls-h) * 0.83);
  padding: calc(var(--controls-h) * 0.17);
}

.ctrlBtn--random svg {
  width: 100%;
  height: 100%;
}

@media (max-width: 480px) {
  .stage {
    padding: 0 8px;
  }
}

/* ---------- Footer ---------- */

footer {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  height: var(--footer-h);
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: var(--bar);
  border-top: 3px solid var(--accent);
  z-index: 20;
}

p {
  font-family: 'Special Elite', cursive;
  text-align: center;
  color: #cfc8ba;
  font-size: 10px;
  margin: 0;
  padding: 0 10px;
}

a {
  text-decoration: none;
}