/* ============================================================
   楓葉幻想 — Maple Fantasy  ·  Design System
   Dreamy night-sky blue→purple, luxe magical
   ============================================================ */
:root{
  /* core night sky */
  --night-0:#0a0820;
  --night-1:#140e36;
  --night-2:#1d1450;
  --night-3:#2a1d6e;
  /* brand gradient (from logo) */
  --ice:#8fd6ff;
  --sky:#6aa8ff;
  --blue:#5b7cff;
  --violet:#9a6cff;
  --magenta:#c77bff;
  --rose:#e8a6ff;
  /* accents */
  --gold:#ffe6a3;
  --star:#fff6d8;
  /* text */
  --ink:#f2ecff;
  --ink-soft:#c9bdf0;
  --ink-dim:#8d82bd;
  /* glass */
  --glass:rgba(40,28,92,.42);
  --glass-2:rgba(28,20,66,.62);
  --border:rgba(160,135,255,.28);
  --border-bright:rgba(170,200,255,.55);
  /* fx */
  --grad-brand:linear-gradient(100deg,var(--ice),var(--sky) 28%,var(--violet) 62%,var(--magenta));
  --grad-btn:linear-gradient(135deg,#7fb6ff,#7d6bff 55%,#b86cff);
  --glow-blue:0 0 28px rgba(106,168,255,.55);
  --glow-violet:0 0 34px rgba(154,108,255,.55);
  --shadow-card:0 22px 60px -22px rgba(0,0,0,.7),0 0 0 1px var(--border) inset;
  --maxw:1240px;
  --font-head:"Noto Serif TC",serif;
  --font-body:"Noto Sans TC",sans-serif;
  --font-disp:"Cinzel",serif;
}
/* 簡體語系改用 Noto SC，避免繁體字型 fallback 造成筆畫粗細不一 */
html[lang="zh-Hans"]{
  --font-head:"Noto Serif SC","Noto Serif TC",serif;
  --font-body:"Noto Sans SC","Noto Sans TC",sans-serif;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;overflow-x:hidden;max-width:100%}
body{
  font-family:var(--font-body);
  color:var(--ink);
  background:var(--night-0);
  line-height:1.6;
  overflow-x:hidden;
  -webkit-font-smoothing:antialiased;
}
img{display:block;max-width:100%}
a{color:inherit;text-decoration:none}
button{font-family:inherit;cursor:pointer;border:none;background:none;color:inherit}
::selection{background:rgba(154,108,255,.45);color:#fff}

/* ---------- ambient backdrop ---------- */
.sky{
  position:fixed;inset:0;z-index:-3;overflow:hidden;
  background:
    radial-gradient(120% 80% at 50% -10%, #355bbf 0%, #2a1d6e 32%, #140e36 62%, #0a0820 100%);
}
.sky::after{ /* horizon glow */
  content:"";position:absolute;left:50%;bottom:-30vh;transform:translateX(-50%);
  width:140vw;height:70vh;border-radius:50%;
  background:radial-gradient(closest-side,rgba(120,150,255,.30),transparent 70%);
  filter:blur(20px);
}
#stars{position:fixed;inset:0;z-index:-2;pointer-events:none}
.moon{
  position:fixed;top:6vh;right:8vw;z-index:-2;width:min(320px,34vw);height:min(320px,34vw);
  border-radius:50%;
  background:radial-gradient(circle at 38% 36%, #fbf7ff, #d7d2ff 45%, rgba(180,170,255,.15) 72%, transparent 73%);
  box-shadow:0 0 90px 30px rgba(190,180,255,.25);
  opacity:.85;pointer-events:none;
}
#leaves{position:fixed;inset:0;z-index:-1;pointer-events:none;overflow:hidden}
.leaf{position:absolute;will-change:transform;opacity:.0}

/* ---------- nav ---------- */
.nav{
  position:fixed;top:0;left:0;right:0;z-index:60;
  display:flex;align-items:center;gap:28px;
  padding:14px clamp(16px,4vw,48px);
  transition:background .35s,backdrop-filter .35s,box-shadow .35s,padding .35s;
}
.nav.scrolled{
  background:linear-gradient(180deg,rgba(13,9,32,.9),rgba(13,9,32,.62));
  backdrop-filter:blur(14px);
  box-shadow:0 1px 0 var(--border),0 12px 30px -18px #000;
  padding-top:10px;padding-bottom:10px;
}
.nav__logo{display:flex;align-items:center;gap:10px;height:42px}
.nav__logo img{height:100%;width:auto;filter:drop-shadow(0 2px 8px rgba(120,140,255,.6))}
.nav__links{display:flex;gap:26px;margin-left:auto}
.nav__links a{
  font-size:15px;font-weight:500;color:var(--ink-soft);letter-spacing:.04em;
  position:relative;padding:6px 2px;transition:color .25s;
}
.nav__links a::after{
  content:"";position:absolute;left:0;right:100%;bottom:-2px;height:2px;
  background:var(--grad-brand);transition:right .3s;border-radius:2px;
}
.nav__links a:hover{color:#fff}
.nav__links a:hover::after{right:0}
.nav__right{display:flex;align-items:center;gap:14px}
.lang{
  display:flex;align-items:center;gap:2px;padding:4px;border-radius:999px;
  background:var(--glass-2);border:1px solid var(--border);
}
.lang button{
  font-size:12.5px;font-weight:600;letter-spacing:.02em;color:var(--ink-dim);
  padding:5px 11px;border-radius:999px;transition:.25s;
}
.lang button.on{color:#fff;background:var(--grad-btn);box-shadow:var(--glow-violet)}
.nav__burger{display:none;flex-direction:column;gap:5px;padding:8px}
.nav__burger span{width:24px;height:2px;background:var(--ink);border-radius:2px;transition:.3s}

/* shared button */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:10px;
  font-weight:700;letter-spacing:.04em;border-radius:14px;
  padding:15px 30px;font-size:16px;position:relative;transition:transform .2s,box-shadow .3s;
  white-space:nowrap;
}
.btn--primary{
  color:#1a103a;background:var(--grad-btn);
  box-shadow:0 12px 30px -8px rgba(140,110,255,.7),0 0 0 1px rgba(255,255,255,.25) inset;
}
.btn--primary:hover{transform:translateY(-3px);box-shadow:0 18px 40px -8px rgba(140,110,255,.85),var(--glow-blue)}
.btn--ghost{
  color:var(--ink);background:var(--glass-2);border:1px solid var(--border-bright);
  backdrop-filter:blur(6px);
}
.btn--ghost:hover{transform:translateY(-3px);border-color:#fff;box-shadow:var(--glow-blue)}
.btn--lg{padding:18px 40px;font-size:18px;border-radius:16px}

/* section scaffolding */
.section{position:relative;padding:clamp(70px,9vw,130px) clamp(16px,4vw,48px)}
.wrap{max-width:var(--maxw);margin:0 auto}
.eyebrow{
  display:inline-flex;align-items:center;gap:10px;
  font-family:var(--font-disp);font-size:13px;letter-spacing:.34em;text-transform:uppercase;
  color:var(--ice);margin-bottom:18px;
}
.eyebrow::before{content:"";width:26px;height:1px;background:var(--grad-brand)}
.h-sec{
  font-family:var(--font-head);font-weight:900;line-height:1.12;
  font-size:clamp(30px,4.6vw,56px);letter-spacing:.01em;
  background:linear-gradient(120deg,#fff,#cdbcff 60%,#b88dff);
  -webkit-background-clip:text;background-clip:text;color:transparent;
}
.sub-sec{color:var(--ink-soft);font-size:clamp(15px,1.4vw,18px);max-width:60ch;margin-top:16px}
.center{text-align:center}
.center .eyebrow::before{display:none}

/* glass card */
.card{
  background:linear-gradient(160deg,var(--glass),var(--glass-2));
  border:1px solid var(--border);border-radius:22px;
  box-shadow:var(--shadow-card);backdrop-filter:blur(10px);
  position:relative;overflow:hidden;
}
.card::before{
  content:"";position:absolute;inset:0;border-radius:inherit;padding:1px;
  background:linear-gradient(140deg,rgba(170,200,255,.6),transparent 40%,transparent 60%,rgba(200,123,255,.5));
  -webkit-mask:linear-gradient(#000 0 0) content-box,linear-gradient(#000 0 0);
  -webkit-mask-composite:xor;mask-composite:exclude;opacity:.7;pointer-events:none;
}

/* ============ HERO ============ */
.hero{
  min-height:100svh;position:relative;display:flex;flex-direction:column;
  align-items:center;justify-content:center;text-align:center;
  padding:120px clamp(16px,4vw,48px) 90px;overflow:hidden;
}
.hero__chars{position:absolute;inset:0;z-index:1;pointer-events:none}
/* official aurora wallpaper, masked + veiled to melt into the night */
.hero__bg{
  position:absolute;inset:0;z-index:0;
  background:url(img/hero_bg.png?v=2) center 24% / cover no-repeat;
  opacity:.5;
  -webkit-mask-image:linear-gradient(to bottom,rgba(0,0,0,.96) 0%,rgba(0,0,0,.92) 42%,rgba(0,0,0,.45) 74%,transparent 95%);
  mask-image:linear-gradient(to bottom,rgba(0,0,0,.96) 0%,rgba(0,0,0,.92) 42%,rgba(0,0,0,.45) 74%,transparent 95%);
}
.hero__veil{
  position:absolute;inset:0;z-index:0;pointer-events:none;
  background:
    radial-gradient(118% 78% at 50% 24%,transparent 0%,rgba(10,8,32,.4) 55%,rgba(10,8,32,.7) 82%),
    linear-gradient(180deg,rgba(10,8,32,.55) 0%,rgba(10,8,32,.34) 30%,rgba(10,8,32,.76) 76%,var(--night-0) 100%);
}
.hero__char{
  position:absolute;bottom:-2%;filter:drop-shadow(0 28px 40px rgba(0,0,0,.55));
  opacity:.96;
}
.hero__char--l{left:-1%;width:min(440px,33vw)}
.hero__char--r{right:-2%;width:min(470px,35vw);transition-delay:.18s}
html.anim-ok .hero__char{
  opacity:0;transform:translateY(60px) scale(.96);
  transition:opacity 1.1s ease,transform 1.1s cubic-bezier(.2,.8,.2,1);
}
html.anim-ok .hero.ready .hero__char{opacity:.96;transform:none}
.hero__inner{position:relative;z-index:3;max-width:880px}
.hero__logo{
  width:min(640px,82vw);margin:0 auto 10px;
  filter:drop-shadow(0 10px 40px rgba(120,140,255,.6));
}
html.anim-ok .hero__logo{
  opacity:0;transform:translateY(-24px) scale(.94);
  transition:opacity .9s ease,transform .9s cubic-bezier(.2,.8,.2,1);
}
html.anim-ok .hero.ready .hero__logo{opacity:1;transform:none}
.hero__tag{
  font-family:var(--font-head);font-weight:700;font-size:clamp(20px,2.7vw,34px);
  letter-spacing:.12em;color:var(--ink);margin-top:6px;
  text-shadow:0 2px 24px rgba(110,140,255,.6);
}
.hero__tag b{
  background:var(--grad-brand);-webkit-background-clip:text;background-clip:text;color:transparent;
}
.hero__desc{color:var(--ink-soft);font-size:clamp(15px,1.5vw,18px);margin:18px auto 0;max-width:46ch}
.hero__cta{display:flex;gap:16px;justify-content:center;flex-wrap:wrap;margin-top:36px}
.hero__stats{
  display:flex;gap:clamp(20px,5vw,64px);justify-content:center;flex-wrap:wrap;
  margin-top:54px;
}
.stat{text-align:center}
.stat b{
  display:block;font-family:var(--font-disp);font-weight:700;
  font-size:clamp(26px,3.4vw,40px);
  background:linear-gradient(120deg,#fff,#bcd0ff);-webkit-background-clip:text;background-clip:text;color:transparent;
}
.stat span{font-size:13px;letter-spacing:.16em;text-transform:uppercase;color:var(--ink-dim)}
.scroll-cue{
  position:absolute;bottom:26px;left:50%;transform:translateX(-50%);z-index:3;
  font-size:11px;letter-spacing:.3em;color:var(--ink-dim);text-transform:uppercase;
  display:flex;flex-direction:column;align-items:center;gap:8px;
}
.scroll-cue i{width:1px;height:34px;background:linear-gradient(var(--ice),transparent);animation:cue 1.8s infinite}
@keyframes cue{0%{transform:scaleY(.2);transform-origin:top}50%{transform:scaleY(1);transform-origin:top}50.1%{transform-origin:bottom}100%{transform:scaleY(.2);transform-origin:bottom}}

/* reveal on scroll — visible by default; the hidden-then-reveal animation
   is opted into only when JS confirms requestAnimationFrame ticks (html.anim-ok).
   In frozen render contexts that never add anim-ok, content stays visible. */
html.anim-ok .reveal{opacity:0;transform:translateY(34px);transition:opacity .8s,transform .8s}
html.anim-ok .reveal.in{opacity:1;transform:none}