/* ===================================================
   地月ECHO — style.css
   =================================================== */

* { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg-deep: #05070d;
  --bg-soft: #0a0e18;
  --ink: #f4f1ea;
  --ink-dim: rgba(244, 241, 234, 0.72);
  --ink-mute: rgba(244, 241, 234, 0.5);
  --gold: #d9b56b;
  --gold-soft: rgba(217, 181, 107, 0.6);
  --gold-line: rgba(217, 181, 107, 0.35);
  --line: rgba(244, 241, 234, 0.14);

  --font-zh: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", sans-serif;
  --font-en: "Georgia", "Times New Roman", "Cormorant Garamond", serif;
}

html, body {
  background: var(--bg-deep);
  color: var(--ink);
  font-family: var(--font-zh);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  line-height: 1.7;
  overflow-x: hidden;
}

body {
  min-height: 100vh;
  background:
    radial-gradient(ellipse at 20% 10%, rgba(40, 60, 120, 0.18), transparent 55%),
    radial-gradient(ellipse at 80% 90%, rgba(80, 50, 30, 0.16), transparent 60%),
    var(--bg-deep);
}

.accent { color: var(--gold); letter-spacing: 0.08em; }

/* ============ 缺失提示 ============ */
.missing-notice {
  position: fixed;
  inset: 0;
  z-index: 9999;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(5, 7, 13, 0.92);
  backdrop-filter: blur(8px);
  padding: 24px;
}
.missing-card {
  max-width: 480px;
  padding: 32px 28px;
  border: 1px solid var(--gold-line);
  background: rgba(10, 14, 24, 0.85);
  text-align: center;
  border-radius: 4px;
}
.missing-title {
  font-size: 18px;
  margin-bottom: 12px;
  color: var(--gold);
  letter-spacing: 0.05em;
}
.missing-text {
  color: var(--ink-dim);
  font-size: 15px;
}
.missing-text code {
  background: rgba(217, 181, 107, 0.12);
  color: var(--gold);
  padding: 1px 6px;
  border-radius: 2px;
  font-size: 13px;
}

/* ============ Hero ============ */
.hero {
  position: relative;
  width: 100%;
  height: 100vh;
  min-height: 640px;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: opacity 0.9s ease, visibility 0.9s ease;
}

.hero.is-hidden {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  height: 0;
  min-height: 0;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background-image: url("assets/poster.jpg");
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  transform: scale(1.06);
  animation: heroZoom 18s ease-out forwards;
}

.hero-bg.no-poster {
  background: radial-gradient(ellipse at 50% 40%, #1a2238 0%, #0a0e18 55%, #03050a 100%);
  animation: none;
  transform: none;
}

@keyframes heroZoom {
  from { transform: scale(1.12); }
  to   { transform: scale(1.0); }
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(180deg, rgba(5,7,13,0.55) 0%, rgba(5,7,13,0.35) 35%, rgba(5,7,13,0.8) 100%),
    linear-gradient(90deg, rgba(5,7,13,0.4) 0%, rgba(5,7,13,0.0) 50%, rgba(5,7,13,0.4) 100%);
}

.hero-grain {
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: 0.08;
  mix-blend-mode: overlay;
  background-image:
    repeating-linear-gradient(
      0deg,
      rgba(255,255,255,0.04) 0,
      rgba(255,255,255,0.04) 1px,
      transparent 1px,
      transparent 3px
    );
}

.hero-inner {
  position: relative;
  z-index: 2;
  text-align: center;
  padding: 0 24px;
  max-width: 900px;
  animation: heroFadeIn 1.4s ease-out 0.2s both;
}

@keyframes heroFadeIn {
  from { opacity: 0; transform: translateY(18px); }
  to   { opacity: 1; transform: translateY(0); }
}

.hero-eyebrow {
  font-family: var(--font-en);
  font-style: italic;
  letter-spacing: 0.42em;
  font-size: 13px;
  color: var(--gold);
  margin-bottom: 28px;
  text-transform: uppercase;
}

.hero-title {
  font-size: clamp(48px, 9vw, 112px);
  font-weight: 300;
  letter-spacing: 0.06em;
  line-height: 1.1;
  margin-bottom: 28px;
  text-shadow: 0 4px 40px rgba(0,0,0,0.6);
}

.hero-title .accent {
  font-weight: 400;
  letter-spacing: 0.14em;
}

.hero-sub {
  font-size: clamp(15px, 1.6vw, 18px);
  color: var(--ink-dim);
  letter-spacing: 0.12em;
  margin-bottom: 40px;
}

.hero-quote {
  font-size: clamp(15px, 1.8vw, 19px);
  color: var(--ink);
  line-height: 2;
  letter-spacing: 0.06em;
  max-width: 640px;
  margin: 0 auto 56px;
  font-weight: 300;
  opacity: 0.95;
}

.hero-cta {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 22px;
}

.btn-primary {
  background: transparent;
  color: var(--ink);
  border: 1px solid var(--gold-line);
  padding: 18px 56px;
  font-family: var(--font-zh);
  font-size: 15px;
  letter-spacing: 0.18em;
  cursor: pointer;
  transition: all 0.4s ease;
  position: relative;
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  min-width: 220px;
  overflow: hidden;
}

.btn-primary::before {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--gold);
  transform: translateX(-101%);
  transition: transform 0.5s cubic-bezier(0.77, 0, 0.18, 1);
  z-index: 0;
}

.btn-primary:hover {
  color: var(--bg-deep);
  border-color: var(--gold);
}

.btn-primary:hover::before {
  transform: translateX(0);
}

.btn-primary > * {
  position: relative;
  z-index: 1;
}

.btn-label-en {
  font-family: var(--font-en);
  font-style: italic;
  font-size: 12px;
  letter-spacing: 0.28em;
  opacity: 0.7;
}

.hero-hint {
  font-size: 12px;
  color: var(--ink-mute);
  letter-spacing: 0.18em;
  line-height: 1.8;
}
.hero-hint .en-hint {
  font-family: var(--font-en);
  font-style: italic;
  font-size: 11px;
  letter-spacing: 0.2em;
}

.hero-scroll {
  position: absolute;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%);
  width: 1px;
  height: 48px;
  background: var(--gold-line);
  overflow: hidden;
}
.hero-scroll span {
  display: block;
  width: 100%;
  height: 16px;
  background: var(--gold);
  animation: scrollDown 2.4s ease-in-out infinite;
}
@keyframes scrollDown {
  0%   { transform: translateY(-100%); }
  60%  { transform: translateY(300%); }
  100% { transform: translateY(300%); }
}

/* ============ Video Section ============ */
.video-section {
  position: fixed;
  inset: 0;
  background: #000;
  z-index: 50;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transition: opacity 0.7s ease;
}

.video-section.is-visible {
  opacity: 1;
}

.video-stage {
  flex: 1;
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px 16px;
  min-height: 0;
}

#film {
  display: block;
  width: 100%;
  height: 100%;
  max-width: 100vw;
  max-height: calc(100vh - 100px);
  object-fit: contain;
  background: #000;
  outline: none;
}

.video-actions {
  display: flex;
  gap: 16px;
  padding: 18px 24px 28px;
  flex-wrap: wrap;
  justify-content: center;
}

.btn-ghost {
  background: transparent;
  color: var(--ink-dim);
  border: 1px solid var(--line);
  padding: 12px 28px;
  font-family: var(--font-zh);
  font-size: 14px;
  letter-spacing: 0.16em;
  cursor: pointer;
  transition: all 0.3s ease;
  min-width: 140px;
}

.btn-ghost:hover {
  color: var(--gold);
  border-color: var(--gold-line);
}

/* ============ About ============ */
.about {
  padding: 140px 24px 100px;
  position: relative;
}

.about-inner {
  max-width: 760px;
  margin: 0 auto;
  text-align: center;
}

.section-title {
  font-size: clamp(28px, 4vw, 44px);
  font-weight: 300;
  letter-spacing: 0.12em;
  margin-bottom: 56px;
  position: relative;
  display: inline-block;
}

.section-title::after {
  content: "";
  display: block;
  width: 40px;
  height: 1px;
  background: var(--gold);
  margin: 24px auto 0;
}

.about-quote {
  font-family: var(--font-zh);
  font-size: clamp(18px, 2.4vw, 24px);
  line-height: 2;
  letter-spacing: 0.08em;
  color: var(--gold);
  margin: 0 auto 56px;
  padding: 32px 0;
  border-top: 1px solid var(--gold-line);
  border-bottom: 1px solid var(--gold-line);
  max-width: 600px;
  font-weight: 300;
}

.about-text {
  font-size: clamp(15px, 1.4vw, 17px);
  color: var(--ink-dim);
  line-height: 2.1;
  letter-spacing: 0.04em;
  margin-bottom: 28px;
  text-align: justify;
  text-justify: inter-ideograph;
}

.about-emph {
  margin-top: 56px;
  font-size: clamp(16px, 1.8vw, 20px);
  color: var(--ink);
  letter-spacing: 0.06em;
  line-height: 1.9;
  font-weight: 300;
}

/* ============ Features ============ */
.features {
  padding: 80px 24px 140px;
}

.features-inner {
  max-width: 1100px;
  margin: 0 auto;
  text-align: center;
}

.features .section-title {
  margin-bottom: 72px;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 24px;
  text-align: left;
}

.feature-card {
  background: rgba(15, 20, 32, 0.55);
  border: 1px solid var(--gold-line);
  padding: 36px 28px 32px;
  position: relative;
  transition: all 0.5s ease;
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
}

.feature-card:hover {
  border-color: var(--gold);
  background: rgba(20, 26, 42, 0.75);
  transform: translateY(-4px);
}

.feature-num {
  font-family: var(--font-en);
  font-style: italic;
  font-size: 13px;
  letter-spacing: 0.3em;
  color: var(--gold);
  margin-bottom: 20px;
  opacity: 0.85;
}

.feature-title {
  font-size: 20px;
  font-weight: 400;
  letter-spacing: 0.1em;
  margin-bottom: 18px;
  color: var(--ink);
}

.feature-desc {
  font-size: 14px;
  color: var(--ink-dim);
  line-height: 1.9;
  letter-spacing: 0.03em;
}

/* ============ Footer ============ */
.footer {
  text-align: center;
  padding: 60px 24px 80px;
  border-top: 1px solid var(--line);
  margin-top: 40px;
}
.footer-title {
  font-size: 22px;
  font-weight: 300;
  letter-spacing: 0.12em;
  margin-bottom: 10px;
}
.footer-en {
  font-family: var(--font-en);
  font-style: italic;
  font-size: 12px;
  letter-spacing: 0.32em;
  color: var(--ink-mute);
}

/* ============ Mobile ============ */
@media (max-width: 720px) {
  .hero { min-height: 580px; height: 100svh; }
  .hero-eyebrow { font-size: 11px; letter-spacing: 0.32em; margin-bottom: 22px; }
  .hero-title { font-size: 56px; letter-spacing: 0.04em; margin-bottom: 22px; }
  .hero-sub { font-size: 14px; letter-spacing: 0.08em; margin-bottom: 32px; }
  .hero-quote { font-size: 15px; line-height: 1.9; margin-bottom: 44px; padding: 0 12px; }
  .btn-primary { padding: 16px 40px; font-size: 14px; min-width: 200px; }
  .hero-scroll { height: 36px; bottom: 24px; }

  .about { padding: 100px 22px 80px; }
  .about-quote { font-size: 17px; padding: 26px 0; }
  .about-text { font-size: 15px; line-height: 2; }

  .features { padding: 60px 22px 100px; }
  .feature-card { padding: 30px 24px 28px; }

  #film { max-height: calc(100svh - 110px); }
  .video-actions { padding: 14px 16px 22px; gap: 12px; }
  .btn-ghost { padding: 12px 22px; font-size: 13px; min-width: 120px; flex: 1; max-width: 180px; }
}

@media (max-width: 380px) {
  .hero-title { font-size: 46px; }
  .btn-primary { min-width: 180px; padding: 14px 32px; }
}

/* 防止 iOS 触发字号自动放大 */
@supports (-webkit-touch-callout: none) {
  body { -webkit-text-size-adjust: 100%; }
}