/* ===== Reset & Base ===== */
*, *::before, *::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-sans);
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
}

img {
  max-width: 100%;
  display: block;
}

a {
  text-decoration: none;
}

button {
  font-family: var(--font-sans);
  cursor: pointer;
}

/* ===== Focus visible ===== */
:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 4px;
}

/* ===== Selection ===== */
::selection {
  background: rgba(44, 212, 197, 0.3);
  color: #fff;
}

/* ===== Scrollbar ===== */
::-webkit-scrollbar {
  width: 10px;
}
::-webkit-scrollbar-track {
  background: #0a0f1d;
}
::-webkit-scrollbar-thumb {
  background: #1e2b48;
  border-radius: 8px;
}
::-webkit-scrollbar-thumb:hover {
  background: #2a3a5f;
}

/* ===== Skip link (accessibility) ===== */
.skip-link {
  position: absolute;
  top: -100%;
  left: 16px;
  z-index: 9999;
  padding: 8px 16px;
  background: var(--accent);
  color: #04121c;
  font-weight: 700;
  border-radius: 0 0 8px 8px;
  transition: top 0.2s;
}
.skip-link:focus {
  top: 0;
}

/* ===== Keyframes ===== */
@keyframes blink {
  0%, 49% { opacity: 1; }
  50%, 100% { opacity: 0; }
}
@keyframes shimmer {
  to { background-position: 200% center; }
}
@keyframes float-a {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-14px); }
}
@keyframes float-b {
  0%, 100% { transform: translate(0, 0); }
  50% { transform: translate(20px, -26px); }
}
@keyframes float-c {
  0%, 100% { transform: translate(0, 0); }
  50% { transform: translate(-24px, 18px); }
}
@keyframes pulse-ring {
  0% { transform: scale(0.9); opacity: 0.7; }
  70% { transform: scale(1.25); opacity: 0; }
  100% { opacity: 0; }
}
@keyframes twinkle {
  0%, 100% { opacity: 0.12; }
  50% { opacity: 1; }
}

/* ===== Ambient Background ===== */
.ambient {
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  overflow: hidden;
}
.ambient__base {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, #080d1a 0%, #0a1124 40%, #080d1a 100%);
}
.ambient__orb--a {
  position: absolute;
  top: -180px;
  left: -120px;
  width: 560px;
  height: 560px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(34, 211, 238, 0.16), transparent 65%);
  filter: blur(20px);
  animation: float-b 16s ease-in-out infinite;
}
.ambient__orb--b {
  position: absolute;
  top: 600px;
  right: -160px;
  width: 620px;
  height: 620px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(45, 212, 191, 0.13), transparent 65%);
  filter: blur(20px);
  animation: float-c 19s ease-in-out infinite;
}
.ambient__orb--c {
  position: absolute;
  bottom: -200px;
  left: 30%;
  width: 520px;
  height: 520px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(99, 102, 241, 0.1), transparent 65%);
  filter: blur(20px);
  animation: float-b 22s ease-in-out infinite;
}

/* ===== Scroll Progress Bar ===== */
.progress-bar-wrap {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  z-index: 120;
  pointer-events: none;
}
.progress-bar {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--accent), var(--accent2));
  box-shadow: 0 0 12px var(--accent);
  transition: width 0.1s linear;
}

/* ===== Section label (mono tag) ===== */
.section-tag {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--accent);
  margin-bottom: 12px;
}

/* ===== Section heading ===== */
.section-title {
  font-size: clamp(30px, 4vw, 46px);
  font-weight: 700;
  letter-spacing: -0.03em;
  margin: 0;
}

/* ===== Utility: position relative, z-index 1 ===== */
.site-wrapper {
  position: relative;
  overflow: hidden;
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  border-radius: 11px;
  padding: 0.85em 1.5em;
  font-weight: 600;
  font-size: 15px;
  font-family: var(--font-sans);
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
  border: none;
  cursor: pointer;
}
.btn:hover {
  transform: translateY(-2px);
}
.btn:active {
  transform: translateY(0);
}
.btn--primary {
  background: var(--accent);
  color: #04121c;
  box-shadow: 0 4px 16px rgba(44, 212, 197, 0.22);
}
.btn--primary:hover {
  box-shadow: 0 8px 22px rgba(44, 212, 197, 0.36);
}
.btn--outline {
  background: transparent;
  color: var(--ink);
  border: 1px solid var(--border);
}
.btn--outline:hover {
  border-color: var(--accent);
}

/* ===== details / FAQ ===== */
details > summary {
  list-style: none;
  cursor: pointer;
}
summary::-webkit-details-marker {
  display: none;
}
details[open] .faq-chev {
  transform: rotate(180deg);
}
details[open] .faq-q {
  color: var(--accent);
}