/* =============================================================
   HOWTO SCROLL — 音を巡る三章の作法
   HERO 直下に配置。文字が呼吸し、道が描かれ、扉が開く。
   ============================================================= */

.howto-scroll {
  position: relative;
  padding: 120px 40px 90px;
  background:
    radial-gradient(ellipse 80% 100% at 50% 35%, rgba(168, 144, 90, 0.10), transparent 60%),
    radial-gradient(ellipse 60% 80% at 50% 85%, rgba(45, 90, 61, 0.08), transparent 70%),
    linear-gradient(180deg, #0a120d 0%, #0d1711 50%, #0a120d 100%);
  color: #e6ecdf;
  font-family: 'Noto Serif JP', serif;
  overflow: hidden;
}

.howto-scroll::before,
.howto-scroll::after {
  content: '';
  position: absolute;
  left: 0; right: 0;
  height: 80px;
  pointer-events: none;
  z-index: 2;
}
.howto-scroll::before {
  top: 0;
  background: linear-gradient(180deg, rgba(10, 18, 13, 0.9), transparent);
}
.howto-scroll::after {
  bottom: 0;
  background: linear-gradient(0deg, rgba(10, 18, 13, 0.9), transparent);
}

/* --- 浮遊粒子 --- */
.hs-particles {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 1;
}
.hs-particles .hs-dot {
  position: absolute;
  width: 3px; height: 3px;
  border-radius: 50%;
  background: rgba(216, 184, 119, 0.55);
  box-shadow: 0 0 8px rgba(216, 184, 119, 0.45);
  opacity: 0;
  animation: hsDrift var(--dur, 9s) ease-in-out infinite var(--delay, 0s);
}
@keyframes hsDrift {
  0%,100% { transform: translate(0, 0); opacity: 0.25; }
  50%     { transform: translate(var(--dx, 10px), calc(-1 * var(--dy, 25px))); opacity: 0.85; }
}

/* --- ヘッダー --- */
.hs-header {
  position: relative;
  z-index: 3;
  max-width: 820px;
  margin: 0 auto 80px;
  text-align: center;
}
.hs-ornament {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 18px;
  margin-bottom: 22px;
}
.hs-ornament-line {
  flex: 1;
  max-width: 140px;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(183, 201, 138, 0.55), transparent);
}
.hs-ornament svg {
  width: 32px; height: 12px;
  stroke: #b7c98a;
  stroke-width: 0.8;
  fill: none;
  stroke-linecap: round;
  filter: drop-shadow(0 0 6px rgba(183, 201, 138, 0.55));
}
.hs-kicker {
  font-family: 'Cinzel', 'Noto Serif JP', serif;
  font-size: 12px;
  letter-spacing: 0.5em;
  color: #b7c98a;
  margin-bottom: 18px;
  text-indent: 0.5em;
  opacity: 0;
  animation: hsFadeIn 1.4s ease-out 0.2s forwards;
}
.hs-title {
  font-family: 'Noto Serif JP', serif;
  font-size: clamp(22px, 3vw, 36px);
  font-weight: 400;
  letter-spacing: 0.18em;
  line-height: 1.65;
  margin: 0;
  color: #e6ecdf;
}
.hs-title-accent {
  color: #d8b877;
  font-weight: 500;
  text-shadow: 0 0 18px rgba(216, 184, 119, 0.25);
}
.hs-title .hs-char {
  display: inline-block;
  opacity: 0;
  transform: translateY(10px);
  animation: hsCharIn 0.8s cubic-bezier(0.22, 1, 0.36, 1) var(--delay, 0s) forwards,
             hsCharFloat 5s ease-in-out calc(1s + var(--delay, 0s)) infinite;
}
@keyframes hsCharIn {
  to { opacity: 1; transform: translateY(0); }
}
@keyframes hsCharFloat {
  0%, 100% { transform: translateY(0); }
  50%      { transform: translateY(-3px); }
}
@keyframes hsFadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* --- タイムライン --- */
.hs-timeline {
  position: relative;
  z-index: 3;
  max-width: 1180px;
  margin: 0 auto;
}

/* 中央の縦道 (SVG でストローク描画) */
.hs-path-svg {
  position: absolute;
  top: 0; bottom: 0;
  left: 50%;
  width: 2px;
  height: 100%;
  transform: translateX(-50%);
  pointer-events: none;
  overflow: visible;
  z-index: 2;
}
.hs-path-line {
  fill: none;
  stroke: #d8b877;
  stroke-width: 1.2;
  stroke-dasharray: 4 6;
  stroke-linecap: round;
  opacity: 0.65;
  filter: drop-shadow(0 0 4px rgba(216, 184, 119, 0.4));
  /* 下記は JS で設定: pathLength, stroke-dashoffset = pathLength */
  stroke-dashoffset: var(--path-offset, 100%);
  transition: stroke-dashoffset 0.4s linear;
}

/* 道のノード */
.hs-path-node {
  position: absolute;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 22px; height: 22px;
  border-radius: 50%;
  background: radial-gradient(circle at 35% 35%, #d8b877, #8a6f35);
  border: 1px solid #d8b877;
  box-shadow:
    0 0 18px rgba(216, 184, 119, 0.55),
    inset 0 0 4px rgba(255, 230, 180, 0.5);
  z-index: 3;
  opacity: 0.5;
  transition: opacity 0.8s ease, box-shadow 0.8s ease, transform 0.8s ease;
}
.hs-path-node::after {
  content: '';
  position: absolute;
  inset: -6px;
  border-radius: 50%;
  border: 1px solid rgba(216, 184, 119, 0.35);
  animation: hsNodePulse 3s ease-in-out infinite;
}
@keyframes hsNodePulse {
  0%, 100% { transform: scale(1); opacity: 0.3; }
  50%      { transform: scale(1.5); opacity: 0; }
}
.hs-path-node.is-active {
  opacity: 1;
  box-shadow:
    0 0 28px rgba(216, 184, 119, 0.9),
    inset 0 0 6px rgba(255, 240, 200, 0.8);
  transform: translate(-50%, -50%) scale(1.1);
}

/* 章 (chapter) */
.hs-chapter {
  display: flex;
  align-items: center;
  gap: 80px;
  margin-bottom: 110px;
  position: relative;
  z-index: 3;
}
.hs-chapter:last-of-type { margin-bottom: 60px; }
.hs-chapter[data-align="left"] { flex-direction: row-reverse; }

/* 初期状態 (非表示) */
.hs-chapter {
  opacity: 0;
  transform: translateY(40px);
  transition: opacity 1.2s ease-out, transform 1.2s cubic-bezier(0.22, 1, 0.36, 1);
}
.hs-chapter.is-visible {
  opacity: 1;
  transform: translateY(0);
}

.hs-chapter-text {
  flex: 1 1 0;
  min-width: 0;
}
.hs-chapter[data-align="right"] .hs-chapter-text { text-align: left; }
.hs-chapter[data-align="left"]  .hs-chapter-text { text-align: right; }

.hs-chapter-kicker {
  font-family: 'Cinzel', 'Noto Serif JP', serif;
  font-size: 11px;
  letter-spacing: 0.5em;
  color: #b7c98a;
  margin-bottom: 14px;
  text-indent: 0.5em;
}

.hs-ord-wrap {
  display: flex;
  align-items: center;
  gap: 18px;
  margin-bottom: 14px;
}
.hs-chapter[data-align="left"] .hs-ord-wrap { justify-content: flex-end; }
.hs-ord {
  font-family: 'Noto Serif JP', serif;
  font-size: 58px;
  font-weight: 300;
  color: #d8b877;
  line-height: 1;
  text-shadow: 0 0 28px rgba(216, 184, 119, 0.45);
  animation: hsOrdBreathe 3.2s ease-in-out infinite;
}
@keyframes hsOrdBreathe {
  0%, 100% {
    text-shadow: 0 0 28px rgba(216, 184, 119, 0.45);
    transform: scale(1);
  }
  50% {
    text-shadow: 0 0 44px rgba(216, 184, 119, 0.8),
                 0 0 70px rgba(183, 201, 138, 0.25);
    transform: scale(1.03);
  }
}
.hs-ord-line {
  width: 44px; height: 1px;
  background: linear-gradient(90deg, rgba(216, 184, 119, 0.6), transparent);
}
.hs-chapter[data-align="left"] .hs-ord-line {
  background: linear-gradient(90deg, transparent, rgba(216, 184, 119, 0.6));
}
.hs-ord-en {
  font-family: 'Cinzel', 'Noto Serif JP', serif;
  font-size: 10px;
  letter-spacing: 0.5em;
  color: rgba(169, 184, 164, 0.85);
  text-indent: 0.5em;
}

.hs-chapter-title {
  font-family: 'Noto Serif JP', serif;
  font-size: clamp(18px, 2vw, 26px);
  font-weight: 400;
  letter-spacing: 0.1em;
  line-height: 1.7;
  margin: 0 0 16px;
  color: #e6ecdf;
}

.hs-verb-wrap {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 18px;
}
.hs-chapter[data-align="left"] .hs-verb-wrap { justify-content: flex-end; }
.hs-verb-sub {
  font-family: 'Cinzel', 'Noto Serif JP', serif;
  font-style: italic;
  font-size: 12px;
  letter-spacing: 0.3em;
  color: #b7c98a;
}
.hs-verb {
  position: relative;
  font-family: 'Noto Serif JP', serif;
  font-size: 15px;
  letter-spacing: 0.45em;
  color: #d8b877;
  padding: 3px 14px 3px 16px;
  border: 1px solid rgba(216, 184, 119, 0.75);
  border-radius: 2px;
  text-indent: 0.45em;
  overflow: hidden;
  background: rgba(216, 184, 119, 0.03);
  text-shadow: 0 0 12px rgba(216, 184, 119, 0.4);
}
.hs-verb::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(
    90deg,
    transparent 0%,
    rgba(255, 230, 180, 0.25) 50%,
    transparent 100%
  );
  transform: translateX(-100%);
  animation: hsVerbSheen 4.5s ease-in-out infinite;
}
@keyframes hsVerbSheen {
  0%, 85%, 100% { transform: translateX(-100%); }
  95% { transform: translateX(100%); }
}

.hs-chapter-desc {
  font-size: 13.5px;
  line-height: 2;
  color: rgba(230, 236, 223, 0.72);
  letter-spacing: 0.08em;
  margin: 0 0 20px;
}

.hs-chapter-hint {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: 'Noto Serif JP', serif;
  font-size: 12px;
  color: #b7c98a;
  letter-spacing: 0.15em;
  font-style: italic;
  margin-bottom: 20px;
}
.hs-chapter-hint svg { width: 14px; height: 14px; flex-shrink: 0; animation: hsHintPulse 2.4s ease-in-out infinite; }
@keyframes hsHintPulse {
  0%, 100% { opacity: 0.5; transform: scale(1); }
  50%      { opacity: 1;   transform: scale(1.15); }
}

/* CTAリンク */
.hs-cta {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 10px 24px;
  font-family: 'Noto Serif JP', serif;
  font-size: 13px;
  letter-spacing: 0.2em;
  color: #f4e9d4;
  background: transparent;
  border: 1px solid rgba(216, 184, 119, 0.55);
  border-radius: 2px;
  text-decoration: none;
  transition: all 0.4s cubic-bezier(0.22, 1, 0.36, 1);
  position: relative;
  overflow: hidden;
  text-indent: 0.2em;
}
.hs-cta::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(216, 184, 119, 0.15), rgba(183, 201, 138, 0.08));
  opacity: 0;
  transition: opacity 0.4s ease;
}
.hs-cta:hover {
  border-color: #d8b877;
  color: #fff;
  box-shadow: 0 0 24px rgba(216, 184, 119, 0.35),
              inset 0 0 12px rgba(216, 184, 119, 0.12);
  transform: translateY(-1px);
}
.hs-cta:hover::before { opacity: 1; }
.hs-cta svg {
  width: 14px; height: 14px;
  stroke: currentColor;
  stroke-width: 1.4;
  fill: none;
  transition: transform 0.4s;
}
.hs-cta:hover svg { transform: translateX(4px); }

/* メダリオン */
.hs-chapter-scene {
  flex: 0 0 320px;
  display: flex;
  justify-content: center;
}
.hs-medallion {
  position: relative;
  width: 300px; height: 300px;
  display: flex; align-items: center; justify-content: center;
}
.hs-medallion-outer {
  position: absolute;
  inset: 0;
  border-radius: 50%;
  border: 1px solid rgba(216, 184, 119, 0.55);
  box-shadow: 0 0 38px rgba(216, 184, 119, 0.22),
              inset 0 0 30px rgba(216, 184, 119, 0.08);
}
.hs-medallion-dashed {
  position: absolute;
  inset: -14px;
  border-radius: 50%;
  border: 1px dashed rgba(183, 201, 138, 0.35);
  opacity: 0.6;
  animation: hsRot 120s linear infinite;
}
@keyframes hsRot { from { transform: rotate(0); } to { transform: rotate(360deg); } }
.hs-medallion-dashed--rev {
  animation: hsRotRev 80s linear infinite;
}
@keyframes hsRotRev { from { transform: rotate(0); } to { transform: rotate(-360deg); } }
.hs-medallion-dashed--rev {
  position: absolute;
  inset: -28px;
  border-radius: 50%;
  border: 1px dashed rgba(216, 184, 119, 0.22);
}
.hs-medallion-inner {
  position: relative;
  z-index: 2;
  width: 220px; height: 220px;
  border-radius: 50%;
  background: radial-gradient(circle at 50% 40%, rgba(20, 30, 22, 0.7), rgba(10, 18, 13, 0.98));
  border: 1px solid rgba(183, 201, 138, 0.25);
  display: flex; align-items: center; justify-content: center;
  overflow: hidden;
}
.hs-medallion-inner::after {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at 50% 30%, rgba(216, 184, 119, 0.2), transparent 70%);
  pointer-events: none;
  animation: hsMedShimmer 5s ease-in-out infinite;
}
@keyframes hsMedShimmer {
  0%, 100% { opacity: 0.6; }
  50%      { opacity: 1; }
}
.hs-medallion-orb {
  position: absolute;
  top: -8px; left: 50%;
  transform: translateX(-50%);
  background: #0a120d;
  padding: 5px;
  border-radius: 50%;
  border: 1px solid #b7c98a;
  box-shadow: 0 0 14px rgba(183, 201, 138, 0.6);
  z-index: 3;
  animation: hsOrbPulse 2.5s ease-in-out infinite;
}
@keyframes hsOrbPulse {
  0%, 100% { box-shadow: 0 0 14px rgba(183, 201, 138, 0.6); }
  50%      { box-shadow: 0 0 22px rgba(183, 201, 138, 1); }
}
.hs-medallion-orb svg { display: block; }

.hs-cardinal {
  position: absolute;
  top: 50%; left: 50%;
  width: 6px; height: 6px;
  border-radius: 50%;
  background: #d8b877;
  box-shadow: 0 0 8px rgba(216, 184, 119, 0.7);
  transform-origin: 0 0;
}
.hs-cardinal--1 { transform: rotate(0deg)   translate(0, -136px) translate(-50%, -50%); }
.hs-cardinal--2 { transform: rotate(90deg)  translate(0, -136px) translate(-50%, -50%); }
.hs-cardinal--3 { transform: rotate(180deg) translate(0, -136px) translate(-50%, -50%); }
.hs-cardinal--4 { transform: rotate(270deg) translate(0, -136px) translate(-50%, -50%); }

/* ======== 扉 (GATE) — 次の8カテゴリへの導線 ======== */
.hs-gate {
  position: relative;
  z-index: 3;
  max-width: 940px;
  margin: 60px auto 0;
  text-align: center;
  padding: 40px 20px 10px;
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 1.5s ease-out, transform 1.5s cubic-bezier(0.22, 1, 0.36, 1);
}
.hs-gate.is-visible {
  opacity: 1;
  transform: translateY(0);
}
.hs-gate-kicker {
  font-family: 'Cinzel', 'Noto Serif JP', serif;
  font-size: 11px;
  letter-spacing: 0.5em;
  color: #b7c98a;
  margin-bottom: 10px;
  text-indent: 0.5em;
}
.hs-gate-title {
  font-family: 'Noto Serif JP', serif;
  font-size: clamp(18px, 2.4vw, 26px);
  font-weight: 400;
  letter-spacing: 0.25em;
  color: #e6ecdf;
  margin: 0 0 6px;
  text-shadow: 0 0 18px rgba(216, 184, 119, 0.35);
}
.hs-gate-sub {
  font-family: 'Noto Serif JP', serif;
  font-size: 12px;
  letter-spacing: 0.3em;
  color: rgba(230, 236, 223, 0.6);
  margin-bottom: 36px;
}

/* 8つの光の輪 (カテゴリを象徴) */
.hs-orbs {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 18px;
  margin: 0 auto 40px;
  flex-wrap: wrap;
  max-width: 600px;
}
.hs-orb {
  position: relative;
  width: 20px; height: 20px;
  border-radius: 50%;
  background: var(--orb-color, rgba(216, 184, 119, 0.8));
  box-shadow: 0 0 12px var(--orb-color, rgba(216, 184, 119, 0.8)),
              inset 0 0 4px rgba(255, 255, 255, 0.35);
  animation: hsOrbFloat var(--orb-dur, 3s) ease-in-out infinite var(--orb-delay, 0s);
}
.hs-orb::before {
  content: '';
  position: absolute;
  inset: -4px;
  border-radius: 50%;
  border: 1px solid var(--orb-color, rgba(216, 184, 119, 0.6));
  opacity: 0.5;
  animation: hsOrbRipple var(--orb-dur, 3s) ease-in-out infinite var(--orb-delay, 0s);
}
@keyframes hsOrbFloat {
  0%, 100% { transform: translateY(0); opacity: 0.75; }
  50%      { transform: translateY(-6px); opacity: 1; }
}
@keyframes hsOrbRipple {
  0%   { transform: scale(1); opacity: 0.6; }
  100% { transform: scale(1.8); opacity: 0; }
}

/* 8つの軌跡 (下へ流れる) */
.hs-gate-arrow {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  color: #d8b877;
  animation: hsGateBreathe 2.8s ease-in-out infinite;
}
@keyframes hsGateBreathe {
  0%, 100% { transform: translateY(0); opacity: 0.65; }
  50%      { transform: translateY(4px); opacity: 1; }
}
.hs-gate-arrow svg {
  width: 18px; height: 18px;
  stroke: currentColor;
  stroke-width: 1.4;
  fill: none;
  stroke-linecap: round;
  stroke-linejoin: round;
}
.hs-gate-arrow-label {
  font-family: 'Cinzel', 'Noto Serif JP', serif;
  font-size: 10px;
  letter-spacing: 0.4em;
  color: rgba(216, 184, 119, 0.7);
  text-indent: 0.4em;
}

/* ============ RESPONSIVE ============ */
@media (max-width: 820px) {
  .howto-scroll { padding: 80px 20px 60px; }
  .hs-header { margin-bottom: 60px; }

  /* モバイル: 左右交互をやめ縦1列中央寄せに */
  .hs-chapter,
  .hs-chapter[data-align="left"],
  .hs-chapter[data-align="right"] {
    flex-direction: column;
    gap: 24px;
    margin-bottom: 70px;
    text-align: center;
  }
  .hs-chapter[data-align="right"] .hs-chapter-text,
  .hs-chapter[data-align="left"]  .hs-chapter-text { text-align: center; }
  .hs-ord-wrap,
  .hs-verb-wrap { justify-content: center; }
  .hs-chapter[data-align="left"] .hs-ord-line {
    background: linear-gradient(90deg, rgba(216, 184, 119, 0.6), transparent);
  }

  /* 中央の道は非表示に (縦1列では不要) */
  .hs-path-svg { display: none; }
  .hs-path-node { display: none; }

  /* メダリオン縮小 */
  .hs-chapter-scene { flex: 0 0 auto; }
  .hs-medallion { width: 200px; height: 200px; }
  .hs-medallion-inner { width: 150px; height: 150px; }
  .hs-medallion-inner svg { width: 120px; height: 120px; }
  .hs-cardinal--1 { transform: rotate(0deg)   translate(0, -94px) translate(-50%, -50%); }
  .hs-cardinal--2 { transform: rotate(90deg)  translate(0, -94px) translate(-50%, -50%); }
  .hs-cardinal--3 { transform: rotate(180deg) translate(0, -94px) translate(-50%, -50%); }
  .hs-cardinal--4 { transform: rotate(270deg) translate(0, -94px) translate(-50%, -50%); }

  .hs-ord { font-size: 42px; }
  .hs-orbs { gap: 10px; }
  .hs-orb { width: 14px; height: 14px; }
}

/* アクセシビリティ: 動き抑制 */
@media (prefers-reduced-motion: reduce) {
  .hs-title .hs-char,
  .hs-ord,
  .hs-orb,
  .hs-orb::before,
  .hs-medallion-dashed,
  .hs-medallion-dashed--rev,
  .hs-verb::before,
  .hs-chapter-hint svg,
  .hs-medallion-orb,
  .hs-gate-arrow,
  .hs-path-node::after {
    animation: none !important;
  }
  .hs-chapter,
  .hs-gate {
    transition: none !important;
    opacity: 1;
    transform: none;
  }
}