/* The Deep Sea Explorer – Free-Floating Organic Presentation Styling */
:root {
  --text-main: #ffffff;
  --text-name: #ffffff;
  --text-blurb: rgba(255, 255, 255, 0.9);
  --accent-cyan: #38bdf8;
  --accent-gold: #facc15;
  --zone-glow: #eabdff;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-tap-highlight-color: transparent;
}

html, body {
  width: 100%;
  min-height: 100%;
  overflow-x: hidden;
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "Outfit", "Segoe UI", sans-serif;
  background-color: #020b18;
  color: var(--text-main);
}

/* App Wrapper */
.app-container {
  width: 100%;
  position: relative;
  overflow: hidden;
}

/* Ocean Depth Continuous Gradient Track */
#ocean-track {
  width: 100%;
  height: 65000px;
  position: relative;
  background: linear-gradient(
    180deg,
    #48dbfb 0%,
    #0abde3 4%,
    #10356c 12%,
    #071a3d 25%,
    #030c1d 40%,
    #020814 65%,
    #01050c 80%,
    #000205 97%,
    #ede5ce 100%
  );
}

#ambient-canvas {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  pointer-events: none;
  z-index: 2;
}

/* Top Navigation Bar */
.top-nav {
  position: fixed;
  top: 16px;
  left: 20px;
  z-index: 100;
  display: flex;
  align-items: center;
  gap: 12px;
}

.nav-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(4, 16, 36, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.15);
  color: var(--text-main);
  text-decoration: none;
  font-size: 0.85rem;
  font-weight: 700;
  padding: 8px 16px;
  border-radius: 50px;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.3);
  transition: all 0.2s ease;
}

.nav-pill:hover {
  background: rgba(14, 35, 70, 0.95);
  transform: translateY(-2px);
}

.nav-actions {
  position: fixed;
  top: 16px;
  right: 20px;
  z-index: 100;
  display: flex;
  align-items: center;
  gap: 10px;
}

.icon-btn {
  background: rgba(4, 16, 36, 0.85);
  backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.15);
  color: var(--text-main);
  padding: 8px 14px;
  border-radius: 50px;
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 700;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.3);
  transition: all 0.2s ease;
}

.icon-btn:hover {
  background: rgba(14, 35, 70, 0.95);
  transform: translateY(-2px);
}

/* Sticky Bottom Telemetry HUD */
.telemetry-hud {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%);
  background: rgba(3, 12, 28, 0.92);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid rgba(56, 189, 248, 0.3);
  border-radius: 24px;
  padding: 12px 28px;
  display: flex;
  align-items: center;
  gap: 24px;
  z-index: 100;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.7), 0 0 20px rgba(56, 189, 248, 0.2);
}

.hud-depth-box {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
}

.hud-depth-number {
  font-family: "Space Mono", monospace;
  font-size: 1.5rem;
  font-weight: 800;
  color: #38bdf8;
  line-height: 1;
}

.hud-depth-label {
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.hud-gauges-box {
  display: flex;
  align-items: center;
  gap: 16px;
  border-left: 1px solid rgba(255, 255, 255, 0.12);
  padding-left: 20px;
}

.gauge-item {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.gauge-value {
  font-family: "Space Mono", monospace;
  font-size: 0.92rem;
  font-weight: 700;
  color: #ffffff;
}

.gauge-title {
  font-size: 0.65rem;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--text-muted);
}

/* Center Depth Guide Line */
.center-depth-line {
  position: fixed;
  top: 50%;
  left: 0;
  width: 100vw;
  height: 1px;
  border-top: 1px dashed rgba(255, 255, 255, 0.12);
  pointer-events: none;
  z-index: 10;
}

/* Surface Title Header */
.surface-header {
  position: absolute;
  top: 80px;
  left: 50%;
  transform: translateX(-50%);
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  width: 90%;
  max-width: 680px;
  z-index: 20;
}

.surface-title {
  font-size: 3.4rem;
  font-weight: 900;
  letter-spacing: -0.02em;
  color: #0f172a;
  text-shadow: 0 2px 12px rgba(255, 255, 255, 0.6);
}

.surface-subtitle {
  font-size: 1.15rem;
  font-weight: 700;
  color: #1e293b;
}

.scroll-indicator {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(8px);
  padding: 8px 22px;
  border-radius: 50px;
  font-size: 0.9rem;
  font-weight: 800;
  color: #0f172a;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.1);
  animation: bounceDown 2s infinite ease-in-out;
}

@keyframes bounceDown {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(8px); }
}

/* 1. Organic Free-Floating Creature Entities */
.creature-entity {
  position: absolute;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  z-index: 20;
  pointer-events: auto;
  transform: translateX(-50%);
  animation: floatCreature 4.5s ease-in-out infinite alternate;
  width: 320px;
}

@keyframes floatCreature {
  0% { transform: translateX(-50%) translateY(0px); }
  100% { transform: translateX(-50%) translateY(8px); }
}

.creature-image {
  max-width: 230px;
  max-height: 160px;
  object-fit: contain;
  filter: drop-shadow(0 8px 24px rgba(0, 0, 0, 0.65));
  transition: transform 0.25s ease;
  margin-bottom: 8px;
}

.creature-image:hover {
  transform: scale(1.08);
}

.creature-image.large-entity {
  max-width: 360px;
  max-height: 220px;
}

.creature-name {
  font-size: 1.05rem;
  font-weight: 900;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-name);
  margin-top: 4px;
  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.9), 0 0 16px rgba(0, 0, 0, 0.8), 0 1px 2px rgba(0, 0, 0, 0.95);
}

.creature-depth-tag {
  font-family: "Space Mono", monospace;
  font-size: 0.76rem;
  font-weight: 800;
  color: var(--accent-cyan);
  text-shadow: 0 2px 8px rgba(0, 0, 0, 0.8);
  margin-top: 2px;
}

.creature-blurb {
  font-size: 0.88rem;
  color: var(--text-blurb);
  width: 100%;
  max-width: 300px;
  line-height: 1.5;
  margin-top: 4px;
  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.9), 0 0 16px rgba(0, 0, 0, 0.8);
}

/* 2. Floating Luminous Zone Milestone Banners */
.zone-milestone-banner {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  width: 90%;
  max-width: 800px;
  text-align: center;
  z-index: 15;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

.zone-milestone-title {
  font-size: 2.8rem;
  font-weight: 900;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--zone-glow);
  text-shadow: 0 0 26px rgba(234, 189, 255, 0.65), 0 2px 12px rgba(0, 0, 0, 0.9);
}

.zone-milestone-desc {
  font-size: 1.05rem;
  font-weight: 600;
  color: rgba(255, 255, 255, 0.85);
  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.9);
}

/* Challenger Deep Floor */
.challenger-deep-floor {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 280px;
  background: linear-gradient(180deg, transparent 0%, #ede5ce 45%);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-end;
  padding-bottom: 40px;
  color: #1e293b;
  z-index: 25;
}

.floor-badge {
  background: #1e293b;
  color: #ede5ce;
  font-family: "Space Mono", monospace;
  font-size: 1.05rem;
  font-weight: 800;
  padding: 12px 26px;
  border-radius: 50px;
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.25);
}

/* Semantic SEO Article Section */
.seo-article {
  position: relative;
  z-index: 30;
  width: 95%;
  max-width: 960px;
  margin: 15px auto 25px auto;
  padding: 20px 24px;
  background: rgba(4, 16, 36, 0.92);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 16px;
  color: var(--text-muted);
  font-size: 0.88rem;
  line-height: 1.6;
}

.seo-article h2 {
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--text-main);
  margin-bottom: 8px;
}

.seo-article h3 {
  font-size: 0.98rem;
  font-weight: 800;
  color: var(--text-main);
  margin: 12px 0 6px 0;
}

/* Responsive Mobile Layout */
@media (max-width: 768px) {
  .surface-title {
    font-size: 2.2rem;
  }
  .zone-milestone-title {
    font-size: 1.8rem;
  }
  .creature-entity {
    width: 260px;
  }
  .creature-image {
    max-width: 170px;
  }
  .creature-image.large-entity {
    max-width: 240px;
  }
  .creature-blurb {
    font-size: 0.82rem;
    max-width: 240px;
  }
  .telemetry-hud {
    width: 92%;
    padding: 10px 16px;
    gap: 14px;
    bottom: 16px;
  }
  .hud-depth-number {
    font-size: 1.2rem;
  }
  .hud-gauges-box {
    padding-left: 12px;
    gap: 10px;
  }
  .gauge-value {
    font-size: 0.82rem;
  }
}