/* Reset / base */
* { box-sizing: border-box; margin: 0; padding: 0; }
html, body { height: 100%; background: #fff; color: #111; font-family: system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif; }
body { overflow: hidden; }

/* Scroll container with snap */
.container {
  height: 100vh;
  width: 100%;
  overflow-y: scroll;
  scroll-snap-type: y mandatory;
  scroll-behavior: smooth;
  -webkit-overflow-scrolling: touch;
}

.container::-webkit-scrollbar { display: none; }

/* Panels (minimalist white shades for seamless blend) */
.panel {
  height: 100vh;
  width: 100%;
  scroll-snap-align: start;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.panel:nth-child(1) { background: #ffffff; }
.panel:nth-child(2) { background: #fafafa; }
.panel:nth-child(3) { background: #f5f5f5; }
.panel:nth-child(4) { background: #f0f0f0; }

/* Content */
.content { text-align: center; max-width: 640px; }
h1 { font-weight: 600; font-size: clamp(28px, 6vw, 42px); margin-bottom: 12px; }
p { font-size: clamp(16px, 3.8vw, 18px); line-height: 1.6; }
.meta { opacity: 0.6; margin-top: 8px; }

/* Floating thin chevron arrows */
.arrow {
  position: fixed;
  left: 50%;
  transform: translateX(-50%);
  width: 44px;    /* generous hit area */
  height: 44px;
  background: transparent;
  border: none;
  cursor: pointer;
  z-index: 999;
  opacity: 0.7;
  transition: opacity 0.2s ease, transform 0.2s ease;
}

.arrow:hover { opacity: 1; }

/* Draw the thin arrowhead with borders */
.arrow::before {
  content: "";
  display: block;
  width: 18px;
  height: 18px;
  margin: 0 auto;
  border-left: 2px solid #000;   /* black thin lines */
  border-bottom: 2px solid #000;
  border-radius: 2px;
  box-shadow: -2px 2px 0px rgba(0,0,0,0.4);
}

/* Orientations */
.arrow.up { top: 12px; }
.arrow.down { bottom: 12px; }

.arrow.up::before { transform: rotate(135deg); }     /* ^ */
.arrow.down::before { transform: rotate(-45deg); }   /* v */

/* Reduce motion preference */
@media (prefers-reduced-motion: reduce) {
  .container { scroll-behavior: auto; }
  .arrow { transition: none; }
}

.bounce-up {
  display: inline-block;
  animation: bounce 1s infinite;
}

@keyframes bounce {
  0%, 20%, 50%, 80%, 100% {
    transform: translateY(0); /* at rest */
  }
  40% {
    transform: translateY(-1px); /* up */
  }
  60% {
    transform: translateY(-3px); /* little up */
  }
}

.bounce-down {
  display: inline-block;
  animation: bounce 1s infinite;
}

@keyframes bounce {
  0%, 20%, 50%, 80%, 100% {
    transform: translateY(0); /* at rest */
  }
  40% {
    transform: translateY(3px); /* up */
  }
  60% {
    transform: translateY(1px); /* little up */
  }
}