/* =========================================================
   Da Nang Pass — Design System
   ========================================================= */

:root {
  /* Brand */
  --terracotta: #C4613A;
  --terracotta-deep: #A04D2D;
  --terracotta-soft: #E69478;
  --ocean: #1B4F72;
  --ocean-deep: #0F3A57;

  /* Surfaces */
  --cream: #FDF8F2;
  --sand: #F5EFE6;
  --paper: #FFFFFF;
  --night: #0D1117;
  --night-2: #161B22;

  /* Ink */
  --ink: #1A1A1A;
  --ink-2: #2D2D2D;
  --mist: #6B7280;
  --mist-2: #9CA3AF;
  --hairline: rgba(26, 26, 26, 0.08);
  --hairline-strong: rgba(26, 26, 26, 0.14);

  /* Type */
  --serif: "Playfair Display", "Iowan Old Style", Georgia, serif;
  --sans: "DM Sans", system-ui, -apple-system, "Segoe UI", sans-serif;
  --mono: "JetBrains Mono", "SF Mono", ui-monospace, monospace;

  /* Motion */
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
  --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);

  /* Layout */
  --nav-h: 68px;
  --page-x: clamp(20px, 4vw, 56px);
  --radius-s: 10px;
  --radius-m: 16px;
  --radius-l: 24px;
  --radius-xl: 32px;
}

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.55;
  color: var(--ink);
  background: var(--cream);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}
img, svg { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
button { font: inherit; cursor: pointer; border: none; background: none; color: inherit; }
input, select { font: inherit; color: inherit; }

/* ---------- Typography ---------- */
h1, h2, h3, h4 {
  font-family: var(--serif);
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.05;
  margin: 0;
  text-wrap: balance;
}
p { margin: 0; text-wrap: pretty; }

.eyebrow {
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--mist);
}

/* ---------- Nav ---------- */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-h);
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--page-x);
  background: rgba(253, 248, 242, 0.72);
  backdrop-filter: blur(14px) saturate(180%);
  -webkit-backdrop-filter: blur(14px) saturate(180%);
  border-bottom: 1px solid transparent;
  transition: background 240ms var(--ease-out), border-color 240ms var(--ease-out), backdrop-filter 240ms var(--ease-out);
}
.nav.scrolled {
  background: rgba(253, 248, 242, 0.86);
  backdrop-filter: blur(22px) saturate(190%);
  -webkit-backdrop-filter: blur(22px) saturate(190%);
  border-bottom-color: var(--hairline);
}
.nav__logo {
  font-family: var(--serif);
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -0.01em;
  display: inline-flex;
  align-items: baseline;
  gap: 4px;
  white-space: nowrap;
  flex-shrink: 0;
}
.nav__logo .t { color: var(--terracotta); }
.nav__logo .o { color: var(--ocean); }

.nav__links {
  display: flex;
  align-items: center;
  gap: 4px;
}
.nav__link {
  padding: 9px 14px;
  border-radius: 999px;
  font-size: 14px;
  font-weight: 500;
  color: var(--ink-2);
  transition: background 180ms var(--ease-out), color 180ms var(--ease-out);
}
.nav__link:hover { background: rgba(26, 26, 26, 0.05); color: var(--ink); }
.nav__link.is-active { background: rgba(196, 97, 58, 0.10); color: var(--terracotta-deep); }

.nav__right { display: flex; align-items: center; gap: 14px; }

.lang-toggle {
  display: inline-flex;
  align-items: center;
  background: rgba(26, 26, 26, 0.06);
  border-radius: 999px;
  padding: 3px;
  position: relative;
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.05em;
}
.lang-toggle button {
  position: relative;
  z-index: 1;
  padding: 6px 12px;
  border-radius: 999px;
  color: var(--mist);
  transition: color 180ms var(--ease-out);
}
.lang-toggle button.is-active { color: var(--paper); }
.lang-toggle__pill {
  position: absolute;
  top: 3px; bottom: 3px;
  width: calc(50% - 3px);
  background: var(--ink);
  border-radius: 999px;
  transition: transform 240ms var(--ease-out);
}
.lang-toggle[data-lang="vi"] .lang-toggle__pill { transform: translateX(100%); }

.menu-btn { display: none; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 22px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 14px;
  letter-spacing: -0.005em;
  transition: transform 220ms var(--ease-out), box-shadow 220ms var(--ease-out), background 220ms var(--ease-out);
  white-space: nowrap;
}
.btn--primary {
  background: var(--terracotta);
  color: var(--paper);
  box-shadow: 0 1px 0 rgba(255,255,255,0.4) inset, 0 6px 18px rgba(196,97,58,0.20);
}
.btn--primary:hover {
  background: var(--terracotta-deep);
  transform: translateY(-2px);
  box-shadow: 0 0 0 3px rgba(196,97,58,0.18),
              0 14px 32px rgba(196,97,58,0.32);
}
.btn--ghost {
  background: rgba(26, 26, 26, 0.05);
  color: var(--ink);
}
.btn--ghost:hover {
  background: rgba(26, 26, 26, 0.10);
  transform: translateY(-2px);
}
.btn--ocean {
  background: var(--ocean);
  color: var(--paper);
  box-shadow: 0 6px 18px rgba(27,79,114,0.22);
}
.btn--ocean:hover {
  background: var(--ocean-deep);
  transform: translateY(-2px);
  box-shadow: 0 0 20px rgba(27,79,114,0.28), 0 14px 32px rgba(27,79,114,0.30);
}
.btn__arrow { transition: transform 220ms var(--ease-out); }
.btn:hover .btn__arrow { transform: translateX(3px); }

/* ---------- Glass ---------- */
.glass {
  background: rgba(255, 255, 255, 0.55);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border: 1px solid rgba(255, 255, 255, 0.55);
  border-top-color: rgba(255, 255, 255, 0.85);
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.6),
    inset 0 -1px 0 rgba(0,0,0,0.04),
    0 8px 32px rgba(20, 20, 20, 0.07);
}
.glass-warm {
  background: rgba(196, 97, 58, 0.10);
  backdrop-filter: blur(16px) saturate(160%);
  -webkit-backdrop-filter: blur(16px) saturate(160%);
  border: 1px solid rgba(196, 97, 58, 0.22);
}
.glass-dark {
  background: rgba(13, 17, 23, 0.55);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border: 1px solid rgba(255,255,255,0.10);
  color: var(--paper);
}

/* ---------- Tilt cards ---------- */
.tilt {
  transform-style: preserve-3d;
  transition: transform 320ms var(--ease-spring), box-shadow 320ms var(--ease-out);
  will-change: transform;
}
.tilt:hover {
  transform: translateY(-6px) rotateX(2.5deg) rotateY(-1.5deg);
  box-shadow:
    0 22px 60px rgba(0,0,0,0.14),
    0 0 40px rgba(196,97,58,0.07);
}

/* ---------- Page enter ---------- */
.page-enter {
  animation: pageEnter 520ms var(--ease-out) both;
}
@keyframes pageEnter {
  from { opacity: 0; transform: translateY(14px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ---------- Reveal on scroll ---------- */
.reveal { opacity: 0; transform: translateY(18px); transition: opacity 600ms var(--ease-out), transform 600ms var(--ease-out); }
.reveal.is-in { opacity: 1; transform: none; }

/* ---------- Footer ---------- */
.footer {
  margin-top: 120px;
  padding: 72px var(--page-x) 40px;
  background: var(--ink);
  color: rgba(255,255,255,0.78);
}
.footer__grid {
  display: grid;
  grid-template-columns: 1.4fr repeat(3, 1fr);
  gap: 48px;
  max-width: 1400px;
  margin: 0 auto;
}
.footer__logo { font-family: var(--serif); font-size: 28px; font-weight: 700; }
.footer__logo .t { color: var(--terracotta-soft); }
.footer__logo .o { color: #6DA8D9; }
.footer__col h4 { font-family: var(--sans); font-size: 12px; font-weight: 600; letter-spacing: 0.16em; text-transform: uppercase; color: rgba(255,255,255,0.55); margin-bottom: 14px; }
.footer__col ul { list-style: none; padding: 0; margin: 0; display: grid; gap: 8px; }
.footer__col a { font-size: 14px; color: rgba(255,255,255,0.78); transition: color 180ms; }
.footer__col a:hover { color: var(--terracotta-soft); }
.footer__bottom {
  max-width: 1400px;
  margin: 56px auto 0;
  padding-top: 28px;
  border-top: 1px solid rgba(255,255,255,0.10);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  font-family: var(--mono);
  color: rgba(255,255,255,0.5);
  letter-spacing: 0.04em;
}

/* ---------- Placeholder imagery (no real photos) ---------- */
.placeholder-img {
  position: relative;
  overflow: hidden;
  background:
    repeating-linear-gradient(135deg,
      rgba(196,97,58,0.10) 0 2px,
      transparent 2px 14px),
    linear-gradient(160deg, #EDD9C7 0%, #E0BFA8 100%);
}
.placeholder-img--ocean {
  background:
    repeating-linear-gradient(135deg,
      rgba(27,79,114,0.10) 0 2px,
      transparent 2px 14px),
    linear-gradient(160deg, #BFD4E3 0%, #8FB1C9 100%);
}
.placeholder-img--night {
  background:
    repeating-linear-gradient(135deg,
      rgba(255,255,255,0.06) 0 2px,
      transparent 2px 14px),
    linear-gradient(160deg, #1F2A36 0%, #0D1117 100%);
}
.placeholder-img--sand {
  background:
    repeating-linear-gradient(135deg,
      rgba(196,97,58,0.10) 0 2px,
      transparent 2px 14px),
    linear-gradient(160deg, #F2E2CC 0%, #DCC4A4 100%);
}
.placeholder-img__label {
  position: absolute;
  bottom: 12px; left: 12px;
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  padding: 5px 9px;
  border-radius: 6px;
  background: rgba(255,255,255,0.78);
  color: var(--ink);
  backdrop-filter: blur(8px);
}
.placeholder-img--night .placeholder-img__label { background: rgba(255,255,255,0.12); color: rgba(255,255,255,0.9); }

/* ---------- Forms / search ---------- */
.search {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 8px 8px 20px;
  border-radius: 999px;
}
.search input {
  flex: 1;
  background: none;
  border: none;
  outline: none;
  font-size: 15px;
  color: var(--ink);
}
.search input::placeholder { color: var(--mist); }

/* ---------- Mobile ---------- */
@media (max-width: 920px) {
  .nav__links { display: none; }
  .menu-btn {
    display: inline-flex;
    width: 38px; height: 38px;
    align-items: center;
    justify-content: center;
    border-radius: 999px;
    background: rgba(26,26,26,0.06);
  }
  .footer__grid { grid-template-columns: 1fr 1fr; gap: 36px; }
  .footer__bottom { flex-direction: column; gap: 12px; align-items: flex-start; }
}