@import url("https://fonts.googleapis.com/css2?family=Noto+Sans+TC:wght@100;300;400;500;700&family=Noto+Serif+TC:wght@300;400;500;600;700&family=Lato:wght@100;300;400;700;900&display=swap");
/* ===========================================
   CSS CUSTOM PROPERTIES
   =========================================== */
:root {
  /* ── Brand ── */
  --brand-purple: #4A1A78;
  --brand-purple-light: #6B2BA8;
  --brand-gold: #F5B800;
  --brand-gold-hover: #D9A300;

  /* ── Index: colors ── */
  --bg-primary: #FAFAFC;
  --bg-gradient: radial-gradient(ellipse 90% 70% at 50% 50%, #F4ECFB 0%, #FAFAFC 75%);
  --card-bg: #4A1A78;
  --card-bg-alt: #6B2BA8;
  --text-primary: #1A0A2E;
  --text-secondary: rgba(26,10,46,0.62);
  --text-on-card: #ffffff;
  --accent: #4A1A78;
  --accent-dim: rgba(74,26,120,0.1);

  /* ── Index: typography ── */
  --font-display: 'Archivo Black', sans-serif;
  --font-body: 'Space Grotesk', sans-serif;
  --title-size: clamp(2.2rem, 6vw, 4.5rem);
  --h2-size: clamp(1.6rem, 4vw, 3rem);
  --h3-size: clamp(1.15rem, 2.8vw, 1.75rem);
  --body-size: clamp(0.9rem, 1.6vw, 1.25rem);
  --small-size: clamp(0.75rem, 1.1vw, 0.95rem);

  /* ── Index: layout ── */
  --slide-padding: clamp(1.5rem, 4vw, 4rem);
  --content-gap: clamp(0.75rem, 2vw, 1.5rem);
  --element-gap: clamp(0.3rem, 1vw, 0.75rem);

  /* ── Index: animation ── */
  --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);
  --duration-normal: 0.6s;

  /* ── Screen-size-tool: colors ── */
  --purple: #5b2d8e;
  --purple-light: #f3eef8;
  --purple-mid: #7a3db8;
  --dark: #2a1a3a;
  --text: #3a3a4a;
  --text-light: #8a8a9a;
  --bg: #ffffff;
  --white: #ffffff;
  --border: #e4e0ee;
  --border-light: #f0eef5;
}

/* ===========================================
   RESPONSIVE :root OVERRIDES (index)
   =========================================== */
@media (max-height: 700px) {
  :root {
    --slide-padding: clamp(0.75rem, 3vw, 2rem);
    --content-gap: clamp(0.4rem, 1.5vw, 1rem);
    --title-size: clamp(1.5rem, 5vw, 3rem);
    --h2-size: clamp(1.3rem, 3.5vw, 2rem);
    --body-size: clamp(0.85rem, 1.4vw, 1.1rem);
  }
}
@media (max-height: 600px) {
  :root {
    --slide-padding: clamp(0.5rem, 2.5vw, 1.5rem);
    --content-gap: clamp(0.3rem, 1vw, 0.75rem);
    --title-size: clamp(1.3rem, 4.5vw, 2.2rem);
    --body-size: clamp(0.8rem, 1.3vw, 1rem);
  }
}
@media (max-height: 500px) {
  :root {
    --slide-padding: clamp(0.4rem, 2vw, 1rem);
    --title-size: clamp(1rem, 3.5vw, 1.5rem);
    --h2-size: clamp(0.9rem, 2.5vw, 1.25rem);
    --body-size: clamp(0.65rem, 1vw, 0.85rem);
  }
}
@media (max-width: 600px) {
  :root { --title-size: clamp(1.25rem, 7vw, 2.5rem); }
}
@media (max-width: 1024px) {
  :root {
    --title-size: clamp(2.2rem, 9.5vw, 3.2rem);
    --h2-size: clamp(1.75rem, 7vw, 2.4rem);
    --h3-size: clamp(1.25rem, 5.2vw, 1.55rem);
    --body-size: clamp(1.05rem, 4.2vw, 1.2rem);
    --small-size: clamp(0.9rem, 3.6vw, 1.02rem);
    --content-gap: 1rem;
    --element-gap: 0.5rem;
    --slide-padding: 1.25rem;
  }
}
@media (max-width: 480px) {
  :root {
    --title-size: clamp(2rem, 9.5vw, 2.6rem);
    --h2-size: clamp(1.55rem, 7vw, 2.1rem);
  }
}
@media (min-width: 768px) and (max-width: 1024px) and (orientation: portrait) {
  :root {
    --title-size: clamp(3rem, 7vw, 4.2rem);
    --h2-size: clamp(2.2rem, 5.5vw, 3.2rem);
    --h3-size: clamp(1.5rem, 3.5vw, 1.95rem);
    --body-size: clamp(1.3rem, 2.6vw, 1.55rem);
    --small-size: clamp(1.05rem, 2.2vw, 1.3rem);
    --content-gap: 1.4rem;
    --element-gap: 0.7rem;
  }
}

/* Reset */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

/* 結構性基礎 */
html {
  scroll-behavior: smooth;
  scroll-padding-top: 64px;
}
html, body {
  overflow-x: hidden;
  font-family: "Noto Sans TC", -apple-system, "Microsoft JhengHei", sans-serif;
}

img {
  display: block;
  width: 100%;
  height: auto;
  vertical-align: bottom;
}

.for_m {
  display: none;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

.text_center {
  text-align: center;
}

.d_flex {
  display: flex;
}

.align_items_center {
  align-items: center;
}

.flex_justify_center {
  justify-content: center;
}

.flex_justify_between {
  justify-content: space-between;
}

.wow {
  opacity: 0;
  visibility: hidden;
  animation-fill-mode: forwards;
}

.wow.animated {
  visibility: visible;
}

.no_scroll {
  overflow: hidden;
}

@media (max-width: 1200px) {
  .for_m {
    display: block !important;
  }

  .for_pc {
    display: none !important;
  }
}

/* ===========================================
   BACK-TO-TOP BUTTON
   =========================================== */
.back-to-top {
  position: fixed;
  right: 35px;
  bottom: 122px;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: var(--brand-purple);
  color: #ffffff;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  padding: 0;
  box-shadow: 0 4px 10px rgba(74, 26, 120, 0.2);
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: opacity 0.3s ease, visibility 0.3s ease, transform 0.3s ease, background 0.2s;
  z-index: 9990;
}
.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
@media(hover: hover) {
  .back-to-top:hover {
    background: var(--brand-purple-light);
    transform: translateY(-3px);
  }
}
.back-to-top svg {
  width: 20px;
  height: 20px;
  stroke: currentColor;
  stroke-width: 2.5;
  fill: none;
  stroke-linecap: round;
  stroke-linejoin: round;
}
@media (max-width: 480px) {
  .back-to-top {
    width: 44px;
    height: 44px;
    right: 35px;
    bottom: 120px;
  }
}