/* ============================================================
   Sichuan Citur Travel — Landing Page
   方向：暗色奢华航空风（墨蓝 × 品牌金 × 编辑部衬线）
   ============================================================ */

:root {
  /* 色板 */
  --ink-950: #060a13;
  --ink-900: #0a1020;
  --ink-850: #0d1528;
  --ink-800: #121b32;
  --ink-700: #1a2542;
  --gold-200: #f6e3b4;
  --gold-300: #eccf8d;
  --gold-400: #ddb45f;
  --gold-500: #c99e3f;
  --gold-600: #a87f28;
  --paper: #f3edde;
  --paper-dim: rgba(243, 237, 222, 0.66);
  --paper-faint: rgba(243, 237, 222, 0.38);
  --hairline: rgba(221, 180, 95, 0.22);
  --hairline-strong: rgba(221, 180, 95, 0.45);

  /* 字体 */
  --font-display: "Songti SC", "Noto Serif SC", "STSong", Georgia, "Times New Roman", serif;
  --font-body: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", -apple-system, "Segoe UI", sans-serif;
  --font-mono: "SF Mono", "Menlo", "Consolas", "Courier New", monospace;

  /* 字号 */
  --text-base: clamp(1rem, 0.94rem + 0.3vw, 1.125rem);
  --text-hero: clamp(3.4rem, 1.6rem + 9vw, 9rem);
  --text-h2: clamp(1.9rem, 1.4rem + 2.2vw, 3.2rem);
  --text-kicker: clamp(0.68rem, 0.64rem + 0.2vw, 0.8rem);

  /* 节奏 */
  --space-section: clamp(5rem, 3.5rem + 6vw, 10rem);
  --gutter: clamp(1.25rem, 4vw, 4rem);
  --content-max: 72rem;

  /* 动效 */
  --duration-fast: 180ms;
  --duration-normal: 420ms;
  --duration-slow: 800ms;
  --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--ink-900);
  color: var(--paper);
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: 1.85;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

a { color: inherit; }

/* ---------- 通用元素 ---------- */

.kicker {
  font-family: var(--font-display);
  font-size: var(--text-kicker);
  letter-spacing: 0.42em;
  text-transform: uppercase;
  color: var(--gold-400);
  margin: 0 0 0.9rem;
}

.section {
  padding: var(--space-section) var(--gutter);
  max-width: calc(var(--content-max) + 2 * var(--gutter));
  margin: 0 auto;
}

.section-head { margin-bottom: clamp(2.5rem, 2rem + 3vw, 4.5rem); }

.section-head h2 {
  font-family: var(--font-display);
  font-size: var(--text-h2);
  font-weight: 600;
  letter-spacing: 0.06em;
  margin: 0;
  line-height: 1.25;
}

.section-head h2::after {
  content: "";
  display: block;
  width: 3.5rem;
  height: 1px;
  margin-top: 1.4rem;
  background: linear-gradient(90deg, var(--gold-400), transparent);
}

.section-sub {
  max-width: 38em;
  color: var(--paper-dim);
  margin: 1.2rem 0 0;
}

.section-sub strong { color: var(--gold-300); font-weight: 600; }

/* ---------- 按钮 ---------- */

.btn {
  display: inline-block;
  padding: 0.85em 2.2em;
  font-size: 0.95rem;
  letter-spacing: 0.18em;
  text-decoration: none;
  border: 1px solid transparent;
  transition: transform var(--duration-fast) ease,
              box-shadow var(--duration-fast) ease,
              background-color var(--duration-fast) ease,
              color var(--duration-fast) ease,
              border-color var(--duration-fast) ease;
}

.btn-gold {
  background: linear-gradient(135deg, var(--gold-300), var(--gold-500));
  color: var(--ink-950);
  font-weight: 600;
}

.btn-gold:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 32px rgba(221, 180, 95, 0.35);
}

.btn-gold:active { transform: translateY(0); }

.btn-ghost {
  border-color: var(--hairline-strong);
  color: var(--gold-200);
}

.btn-ghost:hover {
  border-color: var(--gold-300);
  background: rgba(221, 180, 95, 0.08);
  transform: translateY(-2px);
}

.btn:focus-visible,
a:focus-visible {
  outline: 2px solid var(--gold-300);
  outline-offset: 3px;
}

/* ---------- 顶部导航 ---------- */

.site-nav {
  position: fixed;
  inset: 0 0 auto;
  z-index: 50;
  transition: background-color var(--duration-normal) ease,
              box-shadow var(--duration-normal) ease;
}

.site-nav.scrolled {
  background: rgba(6, 10, 19, 0.88);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  box-shadow: 0 1px 0 var(--hairline);
}

.nav-inner {
  max-width: calc(var(--content-max) + 2 * var(--gutter));
  margin: 0 auto;
  padding: 0.9rem var(--gutter);
  display: flex;
  align-items: center;
  gap: 2rem;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  margin-right: auto;
}

.nav-brand img { width: 44px; height: auto; }

.brand-text { display: flex; flex-direction: column; line-height: 1.25; }

.brand-text strong {
  font-family: var(--font-display);
  font-size: 1.12rem;
  letter-spacing: 0.32em;
}

.brand-text small {
  font-size: 0.62rem;
  letter-spacing: 0.34em;
  color: var(--gold-400);
}

.nav-links {
  display: flex;
  gap: 2.2rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-links a {
  font-size: 0.92rem;
  letter-spacing: 0.12em;
  text-decoration: none;
  color: var(--paper-dim);
  padding: 0.4em 0;
  position: relative;
  transition: color var(--duration-fast) ease;
}

.nav-links a::after {
  content: "";
  position: absolute;
  left: 0; right: 100%; bottom: 0;
  height: 1px;
  background: var(--gold-300);
  transition: right var(--duration-normal) var(--ease-out-expo);
}

.nav-links a:hover { color: var(--gold-200); }
.nav-links a:hover::after { right: 0; }

.nav-cta { padding: 0.6em 1.6em; font-size: 0.88rem; }

@media (max-width: 860px) {
  .nav-links { display: none; }
}

/* ---------- HERO ---------- */

.hero {
  position: relative;
  min-height: 100svh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  overflow: hidden;
  padding: 7rem var(--gutter) 0;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(180deg, rgba(6, 10, 19, 0.55) 0%, rgba(6, 10, 19, 0.25) 45%, var(--ink-900) 96%),
    radial-gradient(ellipse at 70% 30%, rgba(221, 180, 95, 0.12), transparent 55%),
    url("../img/hero-network.jpg") center / cover no-repeat;
  transform: scale(1.06);
  animation: hero-drift 24s var(--ease-out-expo) forwards;
}

@keyframes hero-drift {
  to { transform: scale(1); }
}

.hero-content {
  position: relative;
  max-width: var(--content-max);
  margin: 0 auto;
  width: 100%;
}

.hero h1 {
  font-family: var(--font-display);
  font-size: var(--text-hero);
  font-weight: 600;
  letter-spacing: 0.18em;
  line-height: 1.08;
  margin: 0 0 1.2rem;
  text-shadow: 0 4px 60px rgba(6, 10, 19, 0.8);
}

.hero-sub {
  font-size: clamp(1.1rem, 1rem + 0.8vw, 1.55rem);
  letter-spacing: 0.22em;
  color: var(--gold-200);
  margin: 0 0 0.4rem;
}

.hero-en {
  font-family: var(--font-display);
  font-size: 0.78rem;
  letter-spacing: 0.4em;
  color: var(--paper-faint);
  margin: 0 0 2.8rem;
}

.hero-actions { display: flex; gap: 1.1rem; flex-wrap: wrap; }

.hero-stats {
  position: relative;
  max-width: var(--content-max);
  margin: clamp(3rem, 2rem + 5vh, 6rem) auto 0;
  width: 100%;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border-top: 1px solid var(--hairline);
  padding: 2rem 0 2.6rem;
  gap: 1.5rem;
}

.hero-stats div { min-width: 0; }

.hero-stats dt {
  font-family: var(--font-display);
  font-size: clamp(1.9rem, 1.3rem + 2.4vw, 3.4rem);
  color: var(--gold-300);
  line-height: 1.1;
  font-variant-numeric: tabular-nums;
}

.hero-stats dt i {
  font-style: normal;
  font-size: 0.55em;
  color: var(--gold-500);
}

.hero-stats dd {
  margin: 0.5rem 0 0;
  font-size: 0.85rem;
  letter-spacing: 0.14em;
  color: var(--paper-dim);
}

@media (max-width: 720px) {
  .hero-stats { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 480px) {
  .kicker { letter-spacing: 0.26em; }
  .hero-en { letter-spacing: 0.2em; }
}

/* ---------- 公司简介 ---------- */

.about-grid {
  display: grid;
  grid-template-columns: minmax(0, 5fr) minmax(0, 6fr);
  gap: clamp(2rem, 1.5rem + 3vw, 5rem);
  align-items: start;
}

.about-photo {
  margin: 0;
  position: sticky;
  top: 7rem;
}

.about-photo img {
  border: 1px solid var(--hairline);
  box-shadow: 24px 24px 0 -1px var(--ink-850), 24px 24px 0 0 var(--hairline);
}

.about-photo figcaption {
  margin-top: 1.1rem;
  font-size: 0.8rem;
  letter-spacing: 0.18em;
  color: var(--paper-faint);
}

.about-copy .lede {
  font-family: var(--font-display);
  font-size: clamp(1.4rem, 1.2rem + 1vw, 2rem);
  line-height: 1.6;
  letter-spacing: 0.04em;
  color: var(--gold-200);
  margin: 0 0 1.8rem;
}

.about-copy p { color: var(--paper-dim); margin: 0 0 1.4rem; }

.about-copy strong { color: var(--paper); font-weight: 600; }

.about-points {
  list-style: none;
  margin: 2.4rem 0 0;
  padding: 0;
  display: grid;
  gap: 1.1rem;
}

.about-points li {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
  padding: 1rem 1.3rem;
  border-left: 2px solid var(--gold-500);
  background: linear-gradient(90deg, rgba(221, 180, 95, 0.07), transparent 70%);
}

.about-points strong { letter-spacing: 0.08em; }

.about-points span { font-size: 0.86rem; color: var(--paper-faint); }

@media (max-width: 860px) {
  .about-grid { grid-template-columns: 1fr; }
  .about-photo { position: static; }
}

/* ---------- 发展历程 ---------- */

.timeline-track {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--hairline);
  border: 1px solid var(--hairline);
}

.timeline-track li {
  background: var(--ink-850);
  padding: 2.2rem 1.8rem 2.5rem;
  transition: background-color var(--duration-normal) ease;
}

.timeline-track li:hover { background: var(--ink-800); }

.timeline-track time {
  font-family: var(--font-display);
  font-size: 1.55rem;
  color: var(--gold-300);
  letter-spacing: 0.08em;
}

.timeline-track h3 {
  font-size: 1.05rem;
  letter-spacing: 0.12em;
  margin: 0.9rem 0 0.6rem;
  font-weight: 600;
}

.timeline-track p {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.8;
  color: var(--paper-faint);
}

@media (max-width: 960px) {
  .timeline-track { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 600px) {
  .timeline-track { grid-template-columns: 1fr; }
}

/* ---------- 业务模式 ---------- */

.model { background: var(--ink-850); max-width: none; }

.model > * {
  max-width: var(--content-max);
  margin-left: auto;
  margin-right: auto;
}

.model-grid {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: clamp(1.2rem, 1rem + 2vw, 2.6rem);
  align-items: stretch;
}

.model-card {
  border: 1px solid var(--hairline);
  background:
    radial-gradient(ellipse at top left, rgba(221, 180, 95, 0.08), transparent 60%),
    var(--ink-900);
  padding: clamp(1.8rem, 1.4rem + 2vw, 3rem);
  transition: border-color var(--duration-normal) ease, transform var(--duration-normal) var(--ease-out-expo);
}

.model-card:hover {
  border-color: var(--hairline-strong);
  transform: translateY(-4px);
}

.model-tag {
  display: inline-block;
  font-family: var(--font-display);
  font-size: 0.72rem;
  letter-spacing: 0.4em;
  color: var(--gold-400);
  border: 1px solid var(--hairline);
  padding: 0.45em 1.1em 0.45em 1.4em;
}

.model-card h3 {
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 1.3rem + 1vw, 2.1rem);
  letter-spacing: 0.2em;
  margin: 1.4rem 0 1rem;
  font-weight: 600;
}

.model-card p { color: var(--paper-dim); margin: 0 0 1.4rem; font-size: 0.95rem; }

.model-card ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.55rem;
}

.model-card li {
  font-size: 0.9rem;
  color: var(--paper-dim);
  padding-left: 1.4em;
  position: relative;
}

.model-card li::before {
  content: "✦";
  position: absolute;
  left: 0;
  color: var(--gold-500);
  font-size: 0.75em;
  top: 0.45em;
}

.model-link {
  align-self: center;
  font-family: var(--font-display);
  font-size: clamp(2rem, 1.6rem + 2vw, 3.4rem);
  color: var(--gold-500);
}

@media (max-width: 860px) {
  .model-grid { grid-template-columns: 1fr; }
  .model-link { justify-self: center; }
}

/* ---------- 航线信息板 ---------- */

.board {
  border: 1px solid var(--hairline);
  background: var(--ink-950);
  font-family: var(--font-mono);
}

.board-head,
.board-row {
  display: grid;
  grid-template-columns: minmax(9.5em, 1fr) 2fr minmax(8em, 1fr);
  gap: 1rem;
  padding: 0.95rem 1.6rem;
  align-items: baseline;
}

.board-head {
  font-size: 0.68rem;
  letter-spacing: 0.3em;
  color: var(--paper-faint);
  border-bottom: 1px solid var(--hairline);
}

.board-row {
  border-bottom: 1px dashed rgba(221, 180, 95, 0.12);
  font-size: 0.95rem;
  color: var(--paper-dim);
  transition: background-color var(--duration-fast) ease;
}

.board-row:last-child { border-bottom: 0; }

.board-row:hover { background: rgba(221, 180, 95, 0.05); }

.board-row .code {
  color: var(--gold-300);
  letter-spacing: 0.12em;
  font-weight: 600;
}

.status { font-size: 0.78rem; letter-spacing: 0.1em; }
.status.on { color: #8fce9a; }
.status.new { color: var(--gold-300); }
.status.plan { color: var(--paper-faint); }

@media (max-width: 640px) {
  .board-head, .board-row {
    grid-template-columns: minmax(7.5em, 1fr) 1.6fr;
    padding: 0.85rem 1rem;
  }
  .board-head span:last-child { display: none; }
  .board-row .status { display: none; }
}

/* ---------- 明星航线 ---------- */

.star-route {
  margin-top: clamp(2rem, 1.6rem + 2vw, 3.5rem);
  border: 1px solid var(--hairline);
  background:
    radial-gradient(ellipse at 85% 20%, rgba(221, 180, 95, 0.14), transparent 55%),
    var(--ink-850);
  padding: clamp(1.8rem, 1.4rem + 2.4vw, 3.2rem);
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(0, 1.6fr);
  gap: 2rem;
  align-items: center;
}

.star-title h3 {
  font-family: var(--font-display);
  font-size: clamp(1.7rem, 1.4rem + 1.6vw, 2.6rem);
  letter-spacing: 0.14em;
  margin: 0 0 0.6rem;
  font-weight: 600;
}

.star-note { color: var(--paper-faint); font-size: 0.88rem; letter-spacing: 0.12em; margin: 0; }

.star-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
  margin: 0;
}

.star-stats dt {
  font-family: var(--font-display);
  font-size: clamp(2rem, 1.5rem + 2.4vw, 3.4rem);
  color: var(--gold-300);
  line-height: 1.05;
  font-variant-numeric: tabular-nums;
}

.star-stats dt i { font-style: normal; font-size: 0.45em; color: var(--gold-500); letter-spacing: 0.1em; }

.star-stats dd { margin: 0.4rem 0 0; font-size: 0.84rem; letter-spacing: 0.16em; color: var(--paper-dim); }

@media (max-width: 760px) {
  .star-route { grid-template-columns: 1fr; }
}

/* ---------- 合作伙伴 ---------- */

.partner-grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
}

.partner-grid li {
  border: 1px solid var(--hairline);
  background: var(--ink-850);
  padding: 1.6rem 1.5rem 1.4rem;
  display: flex;
  flex-direction: column;
  transition: border-color var(--duration-normal) ease, transform var(--duration-normal) var(--ease-out-expo);
}

.partner-grid li:hover {
  border-color: var(--gold-500);
  transform: translateY(-4px);
}

.partner-grid strong {
  font-family: var(--font-mono);
  font-size: 1.5rem;
  color: var(--gold-300);
  letter-spacing: 0.1em;
}

.partner-grid span { margin-top: 0.5rem; letter-spacing: 0.1em; font-size: 0.98rem; }

.partner-grid small { color: var(--paper-faint); font-size: 0.76rem; letter-spacing: 0.05em; margin-top: 0.2rem; }

@media (max-width: 900px) { .partner-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 480px) { .partner-grid { grid-template-columns: 1fr; } }

.channel-strip {
  margin-top: clamp(2rem, 1.6rem + 2vw, 3rem);
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border-top: 1px solid var(--hairline);
  border-bottom: 1px solid var(--hairline);
  padding: 1.6rem 0;
  gap: 1.5rem;
}

.channel-strip div { display: flex; flex-direction: column; gap: 0.25rem; }

.channel-strip strong {
  font-family: var(--font-display);
  font-size: 1.5rem;
  color: var(--gold-300);
  letter-spacing: 0.08em;
}

.channel-strip span { font-size: 0.84rem; color: var(--paper-dim); letter-spacing: 0.1em; }

@media (max-width: 760px) { .channel-strip { grid-template-columns: repeat(2, 1fr); } }

/* ---------- CTA 区 ---------- */

.cta-band {
  position: relative;
  padding: var(--space-section) var(--gutter);
  background:
    linear-gradient(180deg, rgba(6, 10, 19, 0.82), rgba(6, 10, 19, 0.82)),
    url("../img/hero-network.jpg") center / cover no-repeat;
  border-top: 1px solid var(--hairline);
  text-align: center;
}

.cta-inner { max-width: 42rem; margin: 0 auto; }

.cta-inner h2 {
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 1.4rem + 2vw, 3rem);
  letter-spacing: 0.12em;
  margin: 0 0 1rem;
  font-weight: 600;
}

.cta-inner p { color: var(--paper-dim); margin: 0 0 2.2rem; }

.cta-inner .hero-actions { justify-content: center; }

/* ---------- 页脚 ---------- */

.site-footer {
  background: var(--ink-950);
  padding: 3.5rem var(--gutter) 2.5rem;
}

.footer-inner {
  max-width: var(--content-max);
  margin: 0 auto;
  display: grid;
  gap: 1.6rem;
}

.footer-brand { display: flex; align-items: center; gap: 1rem; }

.footer-brand strong {
  display: block;
  font-family: var(--font-display);
  letter-spacing: 0.18em;
  font-size: 1.05rem;
}

.footer-brand span {
  font-size: 0.66rem;
  letter-spacing: 0.32em;
  color: var(--gold-500);
}

.footer-links {
  list-style: none;
  margin: 0;
  padding: 1.4rem 0;
  display: flex;
  flex-wrap: wrap;
  gap: 2rem;
  border-top: 1px solid var(--hairline);
  border-bottom: 1px solid var(--hairline);
}

.footer-links a {
  font-size: 0.88rem;
  letter-spacing: 0.14em;
  color: var(--paper-dim);
  text-decoration: none;
  transition: color var(--duration-fast) ease;
}

.footer-links a:hover { color: var(--gold-200); }

.footer-meta, .footer-legal {
  margin: 0;
  font-size: 0.8rem;
  color: var(--paper-faint);
  letter-spacing: 0.08em;
}

.footer-legal a { color: var(--paper-faint); }

/* ---------- 入场动效 ---------- */

.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity var(--duration-slow) var(--ease-out-expo),
              transform var(--duration-slow) var(--ease-out-expo);
}

.reveal.is-visible { opacity: 1; transform: none; }

.reveal.d1 { transition-delay: 90ms; }
.reveal.d2 { transition-delay: 180ms; }
.reveal.d3 { transition-delay: 300ms; }
.reveal.d4 { transition-delay: 420ms; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .hero-bg { animation: none; transform: none; }
  .btn, .model-card, .partner-grid li, .timeline-track li { transition: none; }
}