/* ===========================
   GLOBAL THEME
   =========================== */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html,
body {
  width: 100%;
  height: 100%;
  scroll-behavior: smooth;
}

body {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "SF Pro Text",
    "Segoe UI", Roboto, sans-serif;
  background: radial-gradient(
      circle at 20% 10%,
      rgba(168, 85, 247, 0.26),
      transparent 55%
    ),
    radial-gradient(circle at 80% 20%, rgba(34, 211, 238, 0.18), transparent 52%),
    radial-gradient(circle at 50% 80%, rgba(255, 45, 120, 0.14), transparent 55%),
    radial-gradient(circle at top, #1a0036 0%, #050018 45%, #000 100%);
  color: #eef6ff;
  overflow-x: hidden;
}

::selection {
  background: rgba(124, 255, 251, 0.35);
}

a {
  color: #7cfffb;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.section {
  padding: 5rem min(7vw, 5rem);
  position: relative;
  z-index: 1;
}

.full-viewport {
  height: 100vh;
  padding: 0;
}

.dark-panel {
  background: radial-gradient(
      circle at top left,
      rgba(168, 85, 247, 0.14),
      transparent 55%
    ),
    radial-gradient(circle at top, rgba(34, 211, 238, 0.08), transparent 45%),
    radial-gradient(circle at top, #12002a 0%, #040012 55%, #000 100%);
  border-top: 1px solid rgba(124, 255, 251, 0.16);
  border-bottom: 1px solid rgba(168, 85, 247, 0.18);
}

.section-header {
  margin-bottom: 2.5rem;
  max-width: 900px;
}

.section-header h2 {
  font-size: clamp(2rem, 3vw, 2.6rem);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: #e8f5ff;
}

.section-header p {
  margin-top: 0.75rem;
  color: #a7bdd9;
  line-height: 1.6;
}

/* ===========================
   HEADER
   =========================== */
.eh-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 10;
  padding: 0.75rem min(5vw, 4rem);
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: linear-gradient(
    to bottom,
    rgba(2, 2, 10, 0.96),
    rgba(2, 2, 14, 0.82),
    transparent
  );
  backdrop-filter: blur(18px);
  border-bottom: 1px solid rgba(84, 120, 255, 0.35);
}

.logo {
  display: flex;
  flex-direction: column;
  gap: 0.1rem;
}

.logo-main {
  font-size: 0.92rem;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: #f5fbff;
}

.logo-sub {
  font-size: 0.7rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: #8fb3ff;
}

.main-nav {
  display: flex;
  gap: 1.5rem;
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.main-nav a {
  position: relative;
  color: #d3e2ff;
}

.main-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -0.25rem;
  width: 0;
  height: 1px;
  background: linear-gradient(90deg, #37e0ff, #8b5cff);
  transition: width 0.25s ease-out;
}

.main-nav a:hover::after {
  width: 100%;
}

/* ===========================
   LOADING OVERLAY
   =========================== */
#loading-overlay {
  position: fixed;
  inset: 0;
  background: radial-gradient(circle at center, #05091a 0%, #000 65%, #000 100%);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 1.2rem;
  color: #d7ecff;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  font-size: 0.7rem;
  z-index: 20;
  transition: opacity 0.8s ease-out, visibility 0.8s ease-out;
}

#loading-overlay.hidden {
  opacity: 0;
  visibility: hidden;
}

.loading-core {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: radial-gradient(circle at center, #000 0%, #000 45%, #1d2a4f 100%);
  box-shadow: 0 0 30px rgba(114, 204, 255, 0.7);
}

.loading-ring {
  width: 120px;
  height: 120px;
  border-radius: 999px;
  border: 1px solid rgba(111, 171, 255, 0.25);
  border-top-color: rgba(55, 224, 255, 0.95);
  border-left-color: rgba(184, 120, 255, 0.9);
  animation: loading-spin 1.4s linear infinite;
  box-shadow: 0 0 30px rgba(55, 224, 255, 0.8);
}

@keyframes loading-spin {
  to {
    transform: rotate(360deg);
  }
}

/* ===========================
   HERO / UNIVERSE ENTRY
   =========================== */
#universeCanvas {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
  background: radial-gradient(circle at top, #040720, #000 65%);
  z-index: 0;
}

.hero-overlay {
  position: relative;
  z-index: 2;
  height: 100vh;
  padding-top: 7rem;
  padding-inline: min(7vw, 5rem);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: flex-start;
  pointer-events: none;
}

.hero-overlay h1 {
  font-size: clamp(2.4rem, 5vw, 3.6rem);
  letter-spacing: 0.3em;
  text-transform: uppercase;
  margin-bottom: 0.75rem;
  text-shadow: 0 0 25px rgba(122, 209, 255, 0.8);
}

.hero-subtitle {
  font-size: 1rem;
  max-width: 540px;
  color: #c5dcff;
  line-height: 1.7;
  margin-bottom: 2rem;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  pointer-events: auto;
}

.space-mode-cta {
  margin-top: 1.8rem;
  pointer-events: auto;
}

.space-mode-btn {
  position: relative;
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.2rem;
  padding: 1rem 2.6rem;
  border-radius: 999px;
  border: 1px solid rgba(124, 255, 251, 0.7);
  background: radial-gradient(circle at top left, #1e0648, #050015 60%);
  box-shadow: 0 0 40px rgba(168, 85, 247, 0.7), 0 0 34px rgba(34, 211, 238, 0.5);
  color: #f5fbff;
  font-size: 0.95rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  cursor: pointer;
  overflow: hidden;
}

.space-mode-btn::before {
  content: "";
  position: absolute;
  inset: -1px;
  border-radius: inherit;
  background: conic-gradient(
    from 0deg,
    #7cfffb,
    #a855f7,
    #ff2d78,
    #22d3ee,
    #7cfffb
  );
  opacity: 0.72;
  filter: blur(2px);
  z-index: -1;
  animation: gradient-rotate 8s linear infinite;
}

.space-mode-btn .btn-subtext {
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  opacity: 0.82;
}

.space-mode-btn:hover {
  transform: translateY(-1px);
}

@keyframes gradient-rotate {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(360deg);
  }
}

.primary-btn,
.ghost-btn {
  padding: 0.7rem 1.5rem;
  border-radius: 999px;
  border: 1px solid transparent;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  cursor: pointer;
  background: none;
  color: #e4f1ff;
  transition: background 0.25s ease, color 0.25s ease, transform 0.18s ease,
    box-shadow 0.25s ease, border-color 0.25s ease;
}

.primary-btn {
  background: linear-gradient(120deg, #a855f7, #22d3ee, #ff2d78, #7cfffb);
  background-size: 240% 240%;
  color: #060012;
  box-shadow: 0 0 26px rgba(168, 85, 247, 0.45), 0 0 22px rgba(34, 211, 238, 0.35);
  animation: gradient-shift 6s ease infinite;
}

.primary-btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 0 34px rgba(88, 205, 255, 0.9);
}

.ghost-btn {
  border-color: rgba(124, 255, 251, 0.55);
  background: rgba(8, 3, 24, 0.45);
  backdrop-filter: blur(16px);
}

.ghost-btn:hover {
  background: rgba(18, 6, 45, 0.58);
  transform: translateY(-1px);
  box-shadow: 0 0 20px rgba(124, 255, 251, 0.35), 0 0 22px rgba(255, 45, 120, 0.22);
}

@keyframes gradient-shift {
  0% {
    background-position: 0% 50%;
  }
  50% {
    background-position: 100% 50%;
  }
  100% {
    background-position: 0% 50%;
  }
}

/* ===========================
   MODAL (BLACK HOLE POPUPS)
   =========================== */
.modal {
  position: fixed;
  inset: 0;
  z-index: 30;
  display: grid;
  place-items: center;
  background: rgba(0, 0, 0, 0.55);
  backdrop-filter: blur(10px);
  transition: opacity 0.2s ease, visibility 0.2s ease;
}

.modal.hidden {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.modal-panel {
  width: min(620px, calc(100% - 2rem));
  border-radius: 1.2rem;
  padding: 1.1rem 1.2rem 1.2rem;
  background: linear-gradient(
    135deg,
    rgba(168, 85, 247, 0.18),
    rgba(34, 211, 238, 0.12),
    rgba(255, 45, 120, 0.12)
  );
  border: 1px solid rgba(124, 255, 251, 0.35);
  box-shadow: 0 0 50px rgba(168, 85, 247, 0.35), 0 0 40px rgba(34, 211, 238, 0.22);
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 0.6rem;
}

.modal-header h3 {
  letter-spacing: 0.14em;
  text-transform: uppercase;
  font-size: 0.92rem;
}

.modal-panel p {
  color: #d7e7ff;
  line-height: 1.7;
  font-size: 0.92rem;
}

.modal-close {
  width: 40px;
  height: 40px;
  border-radius: 999px;
  border: 1px solid rgba(124, 255, 251, 0.4);
  background: rgba(0, 0, 0, 0.35);
  color: #eef6ff;
  cursor: pointer;
  transition: transform 0.16s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.modal-close:hover {
  transform: translateY(-1px);
  box-shadow: 0 0 18px rgba(124, 255, 251, 0.32);
  background: rgba(18, 6, 45, 0.5);
}

/* ===========================
   SPACE MODE TOGGLE
   =========================== */
.space-toggle {
  position: fixed;
  right: 1.6rem;
  top: 5rem;
  z-index: 15;
  padding: 0.5rem 1.2rem;
  border-radius: 999px;
  border: 1px solid rgba(124, 255, 251, 0.7);
  background: rgba(3, 4, 20, 0.9);
  color: #f5fbff;
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  cursor: pointer;
  box-shadow: 0 0 20px rgba(124, 255, 251, 0.45);
}

.space-toggle.hidden {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.scroll-indicator {
  position: absolute;
  left: min(7vw, 5rem);
  bottom: 2.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  align-items: flex-start;
  font-size: 0.7rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: #9db6ff;
}

.scroll-line {
  width: 1px;
  height: 52px;
  background: linear-gradient(to bottom, #9ae8ff, transparent);
  position: relative;
  overflow: hidden;
}

.scroll-line::before {
  content: "";
  position: absolute;
  top: -20%;
  left: 0;
  width: 100%;
  height: 20px;
  background: linear-gradient(to bottom, #9ae8ff, transparent);
  animation: scroll-pulse 1.5s infinite;
}

@keyframes scroll-pulse {
  0% {
    transform: translateY(0);
    opacity: 1;
  }
  100% {
    transform: translateY(120%);
    opacity: 0;
  }
}

/* ===========================
   SPACE TOOLTIP
   =========================== */
.space-tooltip {
  position: fixed;
  right: min(5vw, 4rem);
  bottom: 4.5rem;
  max-width: 280px;
  padding: 1rem 1.2rem;
  border-radius: 1rem;
  background: radial-gradient(circle at top, #091226, #020412);
  box-shadow: 0 0 26px rgba(102, 194, 255, 0.7);
  border: 1px solid rgba(121, 187, 255, 0.75);
  z-index: 5;
}

.space-tooltip.hidden {
  opacity: 0;
  pointer-events: none;
  transform: translateY(10px);
  transition: opacity 0.2s ease, transform 0.2s ease;
}

.space-tooltip h3 {
  font-size: 0.8rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  margin-bottom: 0.4rem;
  color: #e7f3ff;
}

.space-tooltip p {
  font-size: 0.78rem;
  color: #b5d0ff;
  line-height: 1.5;
}

/* ===========================
   LAB SECTION
   =========================== */
.lab-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.7fr) minmax(0, 1.1fr);
  gap: 2.5rem;
}

.lab-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.2rem;
}

.lab-card {
  background: radial-gradient(circle at top left, #131c3f, #060918 55%, #040613 100%);
  border-radius: 1.1rem;
  padding: 1.2rem 1.2rem 1.3rem;
  border: 1px solid rgba(92, 146, 255, 0.45);
  box-shadow: 0 0 24px rgba(0, 0, 0, 0.9);
  position: relative;
  overflow: hidden;
}

.lab-card::before {
  content: "";
  position: absolute;
  inset: -40%;
  background: radial-gradient(
    circle at top left,
    rgba(75, 197, 255, 0.26),
    transparent 55%
  );
  opacity: 0;
  transition: opacity 0.3s ease;
}

.lab-card:hover::before {
  opacity: 1;
}

.lab-card h3 {
  font-size: 1rem;
  margin-bottom: 0.4rem;
}

.lab-card p,
.lab-card ul {
  font-size: 0.82rem;
  color: #b4ccff;
  line-height: 1.6;
}

.lab-card ul {
  margin-left: 1.1rem;
}

.lab-focus-btn {
  margin-top: 0.8rem;
}

.lab-diagram-panel {
  background: radial-gradient(circle at top, #151e3c, #02020a 60%);
  border-radius: 1.2rem;
  padding: 1.4rem 1.4rem 1.6rem;
  border: 1px solid rgba(108, 161, 255, 0.65);
  box-shadow: 0 0 38px rgba(50, 137, 255, 0.75);
}

.lab-diagram-panel h3 {
  font-size: 0.95rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  margin-bottom: 0.5rem;
}

.lab-diagram-text {
  font-size: 0.82rem;
  color: #c5d9ff;
  margin-bottom: 1rem;
}

.inline-tag {
  background: rgba(66, 162, 255, 0.15);
  border-radius: 0.75rem;
  padding: 0.1rem 0.6rem;
  border: 1px solid rgba(115, 183, 255, 0.6);
}

.diagram-legend {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  font-size: 0.8rem;
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.legend-swatch {
  width: 18px;
  height: 10px;
  border-radius: 999px;
}

.swatch-core {
  background: radial-gradient(circle at center, #000, #1f2c4b);
}
.swatch-horizon {
  background: linear-gradient(90deg, #f9f9ff, #6474ff);
}
.swatch-disk {
  background: linear-gradient(90deg, #ff9b40, #ff3c7f);
}
.swatch-photon {
  background: linear-gradient(90deg, #f3ff9c, #64fff0);
}

/* ===========================
   JOURNEY TIMELINE
   =========================== */
.journey-track {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 1.5rem;
  position: relative;
}

.journey-stage {
  background: radial-gradient(circle at top, #171f3c, #050716 60%);
  border-radius: 1.2rem;
  padding: 1.1rem 1.2rem 1.3rem;
  border: 1px solid rgba(100, 151, 255, 0.5);
  box-shadow: 0 0 28px rgba(0, 0, 0, 0.85);
  transform-origin: center;
  transform: translateY(12px) scale(0.98);
  opacity: 0;
  transition: transform 0.45s ease-out, opacity 0.45s ease-out,
    box-shadow 0.45s ease-out, border-color 0.45s ease-out;
}

.journey-stage.visible {
  opacity: 1;
  transform: translateY(0) scale(1);
  box-shadow: 0 0 42px rgba(86, 158, 255, 0.65);
  border-color: rgba(133, 193, 255, 0.95);
}

.journey-stage h3 {
  font-size: 0.98rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  margin-bottom: 0.5rem;
}

.journey-stage p {
  font-size: 0.84rem;
  color: #c3d6ff;
  line-height: 1.7;
}

/* ===========================
   ASSISTANT
   =========================== */
.assistant-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.7fr) minmax(0, 1.1fr);
  gap: 2.5rem;
}

.assistant-console {
  background: radial-gradient(circle at top, #071322, #020511 65%);
  border-radius: 1.2rem;
  border: 1px solid rgba(96, 168, 255, 0.7);
  box-shadow: 0 0 40px rgba(75, 159, 255, 0.75);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  min-height: 260px;
}

.assistant-log {
  flex: 1;
  padding: 1rem 1.2rem;
  font-family: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Monaco,
    Consolas, "Liberation Mono", "Courier New", monospace;
  font-size: 0.78rem;
  color: #c7e4ff;
  overflow-y: auto;
  max-height: 280px;
}

.assistant-message {
  margin-bottom: 0.6rem;
  line-height: 1.5;
}

.assistant-message.system {
  color: #7ed1ff;
}

.assistant-message.user {
  color: #e2f5ff;
}

.assistant-message.ai {
  color: #9bf0ff;
}

.assistant-form {
  display: flex;
  gap: 0.65rem;
  border-top: 1px solid rgba(70, 120, 198, 0.8);
  padding: 0.7rem 0.9rem 0.8rem;
  background: linear-gradient(to right, #04091c, #071322);
}

.assistant-form input {
  flex: 1;
  padding: 0.55rem 0.9rem;
  border-radius: 999px;
  border: 1px solid rgba(108, 165, 255, 0.75);
  background: radial-gradient(circle at top, #020716, #02020a);
  color: #e3f4ff;
  font-size: 0.8rem;
}

.assistant-form input::placeholder {
  color: #6d87ba;
}

.assistant-hints {
  background: radial-gradient(circle at top, #081631, #030616 70%);
  border-radius: 1.1rem;
  padding: 1.1rem 1.3rem 1.3rem;
  border: 1px dashed rgba(112, 167, 255, 0.8);
  color: #c4d9ff;
  font-size: 0.84rem;
}

.assistant-hints h3 {
  font-size: 0.92rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  margin-bottom: 0.6rem;
}

.assistant-hints ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

/* ===========================
   GAME
   =========================== */
.game-layout {
  display: grid;
  grid-template-columns: minmax(0, 2fr) minmax(0, 1.1fr);
  gap: 2rem;
  align-items: flex-start;
}

#gameCanvas {
  width: 100%;
  max-width: 100%;
  border-radius: 1.1rem;
  background: radial-gradient(circle at left, #02040c 0%, #000 55%, #000 100%);
  border: 1px solid rgba(90, 133, 233, 0.8);
  box-shadow: 0 0 40px rgba(42, 117, 250, 0.8);
}

.game-hud {
  background: radial-gradient(circle at top, #0a1230, #030518 70%);
  border-radius: 1.1rem;
  padding: 1.2rem 1.4rem 1.3rem;
  border: 1px solid rgba(105, 159, 255, 0.7);
  color: #c7ddff;
  font-size: 0.84rem;
}

.hud-line {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  margin-bottom: 0.9rem;
}

.hud-label {
  font-size: 0.74rem;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: #92b3ff;
}

.hud-value {
  font-size: 0.86rem;
}

/* ===========================
   FOOTER
   =========================== */
.eh-footer {
  padding: 1.7rem min(7vw, 5rem) 2.2rem;
  font-size: 0.78rem;
  color: #7d94c1;
  opacity: 0.9;
}

/* ===========================
   RESPONSIVE
   =========================== */
@media (max-width: 900px) {
  .eh-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
  }

  .main-nav {
    width: 100%;
    justify-content: space-between;
    flex-wrap: wrap;
    row-gap: 0.4rem;
  }

  .hero-overlay {
    align-items: flex-start;
    padding-inline: 1.5rem;
  }

  .lab-layout,
  .assistant-layout,
  .game-layout {
    grid-template-columns: minmax(0, 1fr);
  }

  .space-tooltip {
    position: fixed;
    right: 1.2rem;
    left: 1.2rem;
    bottom: 4.5rem;
  }
}

@media (max-width: 600px) {
  .hero-actions {
    flex-direction: column;
    align-items: stretch;
    width: 100%;
  }

  .section {
    padding-inline: 1.5rem;
  }
}