/* =========================================================
   ASURA — style.css
   Dark × Occult Japanese Modern × Dark Fantasy
   ========================================================= */

/* ---------- Custom Properties ---------- */
:root {
  --black:      #0d0d0d;
  --charcoal:   #1a1a1a;
  --crimson:    #8b0000;
  --crimson-lt: #b00000;
  --gold:       #c9a84c;
  --gold-lt:    #e8c96a;
  --white:      #f0ead6;
  --muted:      #7a7060;

  --font-en:    'Cinzel', 'Playfair Display', serif;
  --font-ja:    'Noto Serif JP', serif;

  --transition: 0.35s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  background-color: var(--black);
  color: var(--white);
  font-family: var(--font-ja);
  line-height: 1.7;
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
}

ul {
  list-style: none;
}

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

/* ---------- Container ---------- */
.container {
  width: min(90%, 1100px);
  margin-inline: auto;
}

/* =========================================================
   HERO SECTION
   ========================================================= */

.hero {
  position: relative;
  min-height: 100svh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

/* — Background layer — */
.hero__bg {
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at 50% 80%, #3d0000 0%, #1a0000 35%, var(--black) 70%);
  z-index: 0;
}

/* ---- Sigil (呪術幾何学模様) ---- */
.sigil {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: min(600px, 90vw);
  aspect-ratio: 1;
  opacity: 0.08;
  animation: sigilRotate 60s linear infinite;
}

.sigil::before,
.sigil::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: 50%;
}

/* Outer ring */
.sigil::before {
  border: 2px solid var(--gold);
  box-shadow:
    0 0 0 12px transparent,
    0 0 0 14px var(--gold),
    0 0 0 30px transparent,
    0 0 0 32px var(--crimson);
}

/* Inner geometric — triangle via clip-path pseudo element not supported, use outline trick */
.sigil::after {
  inset: 15%;
  border: 1px solid var(--gold);
  transform: rotate(30deg);
  box-shadow: 0 0 0 8px transparent, 0 0 0 10px var(--crimson);
}

/* Extra CSS-only hexagram lines via box-shadow */
.sigil {
  background:
    /* horizontal bar */
    linear-gradient(0deg, transparent calc(50% - 0.5px), var(--gold) calc(50% - 0.5px), var(--gold) calc(50% + 0.5px), transparent calc(50% + 0.5px)),
    /* vertical bar */
    linear-gradient(90deg, transparent calc(50% - 0.5px), var(--gold) calc(50% - 0.5px), var(--gold) calc(50% + 0.5px), transparent calc(50% + 0.5px)),
    /* diagonal 1 */
    linear-gradient(45deg, transparent calc(50% - 0.5px), var(--crimson) calc(50% - 0.5px), var(--crimson) calc(50% + 0.5px), transparent calc(50% + 0.5px)),
    /* diagonal 2 */
    linear-gradient(135deg, transparent calc(50% - 0.5px), var(--crimson) calc(50% - 0.5px), var(--crimson) calc(50% + 0.5px), transparent calc(50% + 0.5px));
}

@keyframes sigilRotate {
  to { transform: translate(-50%, -50%) rotate(360deg); }
}

/* ---- Flames ---- */
.flame-container {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 40%;
  display: flex;
  align-items: flex-end;
  justify-content: space-around;
  pointer-events: none;
}

.flame {
  display: block;
  border-radius: 50% 50% 20% 20% / 60% 60% 40% 40%;
  filter: blur(6px);
  animation: flameRise var(--dur, 2.5s) ease-in-out infinite alternate;
  transform-origin: bottom center;
}

.f1 { width: 60px;  height: 120px; background: radial-gradient(ellipse at 50% 80%, #ff4500, #8b0000 60%, transparent); --dur: 2.1s; opacity: 0.7; }
.f2 { width: 40px;  height: 90px;  background: radial-gradient(ellipse at 50% 80%, #ff6200, #6b0000 60%, transparent); --dur: 2.8s; opacity: 0.55; }
.f3 { width: 80px;  height: 160px; background: radial-gradient(ellipse at 50% 80%, #ff3000, #900000 60%, transparent); --dur: 2.3s; opacity: 0.65; }
.f4 { width: 50px;  height: 100px; background: radial-gradient(ellipse at 50% 80%, #ff5500, #7a0000 60%, transparent); --dur: 3.0s; opacity: 0.6;  }
.f5 { width: 35px;  height: 70px;  background: radial-gradient(ellipse at 50% 80%, #ff7700, #5a0000 60%, transparent); --dur: 1.9s; opacity: 0.5;  }

@keyframes flameRise {
  0%   { transform: scaleY(1)   scaleX(1)   translateY(0); }
  40%  { transform: scaleY(1.15) scaleX(0.92) translateY(-8px); }
  100% { transform: scaleY(0.85) scaleX(1.08) translateY(4px); }
}

/* ---- Smoke ---- */
.smoke-container {
  position: absolute;
  bottom: 30%;
  left: 0;
  right: 0;
  height: 40%;
  pointer-events: none;
  overflow: hidden;
}

.smoke {
  position: absolute;
  bottom: 0;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(40,15,15,0.6) 0%, transparent 70%);
  animation: smokeRise var(--sdur, 6s) ease-out infinite;
  filter: blur(20px);
}

.s1 { width: 200px; height: 200px; left: 20%; --sdur: 5s;  animation-delay: 0s; }
.s2 { width: 150px; height: 150px; left: 50%; --sdur: 7s;  animation-delay: 1.5s; }
.s3 { width: 180px; height: 180px; left: 70%; --sdur: 6.5s; animation-delay: 3s; }

@keyframes smokeRise {
  0%   { transform: translateY(0) scale(0.5); opacity: 0; }
  20%  { opacity: 0.6; }
  100% { transform: translateY(-300px) scale(2); opacity: 0; }
}

/* ---- Ember canvas ---- */
.ember-canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 0;
}

/* ---- Hero entrance animations ---- */
@keyframes heroFadeUp {
  from { opacity: 0; transform: translateY(28px); }
  to   { opacity: 1; transform: translateY(0); }
}

.hero__image-wrap {
  animation: heroFadeUp 1s cubic-bezier(0.22, 1, 0.36, 1) 0.2s both;
}

.hero__title-en {
  animation: heroFadeUp 1s cubic-bezier(0.22, 1, 0.36, 1) 0.5s both;
}

.hero__catch {
  animation: heroFadeUp 1s cubic-bezier(0.22, 1, 0.36, 1) 0.8s both;
}

.btn--primary {
  animation: heroFadeUp 1s cubic-bezier(0.22, 1, 0.36, 1) 1.05s both;
}

/* ---- Hero bottom fade to songs ---- */
.hero::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 180px;
  background: linear-gradient(to bottom, transparent, var(--black));
  z-index: 1;
  pointer-events: none;
}

/* — Content layer — */
.hero__content {
  position: relative;
  z-index: 1;
  text-align: center;
  padding: 4rem 1.5rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.2rem;
}

/* ---- Hero image placeholder ---- */
.hero__image-wrap {
  width: min(260px, 58vw);
  aspect-ratio: 1;
  border-radius: 50%;
  overflow: hidden;
  border: 2px solid rgba(201, 168, 76, 0.9);
  box-shadow:
    0 0 24px rgba(201, 168, 76, 0.45),
    0 0 70px rgba(139, 0, 0, 0.55),
    inset 0 0 28px rgba(0, 0, 0, 0.55);
  background: var(--charcoal);
  display: flex;
  align-items: center;
  justify-content: center;
}


.hero__image-wrap::after {
  content: '';
  position: absolute;
  inset: -8px;
  border-radius: 50%;
  border: 1px solid rgba(176, 0, 0, 0.55);
  box-shadow: 0 0 30px rgba(132, 35, 255, 0.28);
  pointer-events: none;
}

.hero__img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center center;
  opacity: 0.96;
}

/* ---- Title ---- */
.hero__title {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.2rem;
  line-height: 1;
}

.hero__title-en {
  font-family: var(--font-en);
  font-size: clamp(4rem, 14vw, 10rem);
  font-weight: 900;
  letter-spacing: 0.15em;
  color: var(--gold);
  text-shadow:
    0 0 20px rgba(201, 168, 76, 0.8),
    0 0 60px rgba(201, 168, 76, 0.4),
    2px 2px 0 rgba(139, 0, 0, 0.6);
  animation: titleGlow 3s ease-in-out infinite alternate;
}

.hero__title-ja {
  font-family: var(--font-ja);
  font-size: clamp(1rem, 3vw, 1.6rem);
  font-weight: 300;
  letter-spacing: 0.5em;
  color: var(--muted);
}

@keyframes titleGlow {
  from { text-shadow: 0 0 20px rgba(201,168,76,0.8), 0 0 60px rgba(201,168,76,0.4), 2px 2px 0 rgba(139,0,0,0.6); }
  to   { text-shadow: 0 0 30px rgba(201,168,76,1),   0 0 80px rgba(201,168,76,0.6), 2px 2px 0 rgba(139,0,0,0.8); }
}

/* ---- Catch copy ---- */
.hero__catch {
  font-family: var(--font-ja);
  font-size: clamp(1rem, 3.5vw, 1.4rem);
  font-weight: 300;
  letter-spacing: 0.25em;
  color: rgba(240, 234, 214, 0.85);
  position: relative;
}

.hero__catch::before,
.hero__catch::after {
  content: '—';
  margin-inline: 0.8em;
  color: var(--gold);
  opacity: 0.6;
}

/* ---- CTA Button ---- */
.btn {
  display: inline-block;
  font-family: var(--font-ja);
  font-size: 0.9rem;
  letter-spacing: 0.2em;
  padding: 0.8em 2.4em;
  border: 1px solid currentColor;
  transition: var(--transition);
  cursor: pointer;
  margin-top: 0.5rem;
}

.btn--primary {
  color: var(--gold);
  border-color: var(--gold);
  background: transparent;
  position: relative;
  overflow: hidden;
}

.btn--primary::before {
  content: '';
  position: absolute;
  inset: 0;
  background: var(--gold);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition);
  z-index: -1;
}

.btn--primary:hover {
  color: var(--black);
}

.btn--primary:hover::before {
  transform: scaleX(1);
}

/* =========================================================
   SECTION TITLES
   ========================================================= */

.section-title {
  text-align: center;
  margin-bottom: 3rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.3rem;
}

.section-title__en {
  font-family: var(--font-en);
  font-size: clamp(2rem, 6vw, 3.5rem);
  font-weight: 700;
  color: var(--gold);
  letter-spacing: 0.2em;
}

.section-title__ja {
  font-family: var(--font-ja);
  font-size: clamp(0.75rem, 2vw, 0.95rem);
  letter-spacing: 0.4em;
  color: var(--muted);
}

/* =========================================================
   SONGS SECTION
   ========================================================= */

.songs {
  padding: 6rem 0;
  background: linear-gradient(180deg, var(--black) 0%, var(--charcoal) 50%, var(--black) 100%);
  position: relative;
}

/* Top divider */
.songs::before {
  content: '';
  display: block;
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 1px;
  height: 100px;
  background: linear-gradient(to bottom, var(--gold), rgba(201,168,76,0.2));
  box-shadow: 0 0 8px rgba(201,168,76,0.4);
}

/* ---- Grid ---- */
.song-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 1.5rem;
}

/* ---- Artist Card ---- */
.artist-card {
  background: linear-gradient(135deg, rgba(26,26,26,0.9) 0%, rgba(20,5,5,0.9) 100%);
  border: 1px solid rgba(201, 168, 76, 0.2);
  padding: 1.5rem;
  position: relative;
  transition: var(--transition);
  overflow: hidden;
}

/* corner accent */
.artist-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 30px;
  height: 30px;
  border-top: 1px solid var(--gold);
  border-left: 1px solid var(--gold);
  opacity: 0.7;
  transition: var(--transition);
}

.artist-card::after {
  content: '';
  position: absolute;
  bottom: 0;
  right: 0;
  width: 30px;
  height: 30px;
  border-bottom: 1px solid var(--crimson);
  border-right: 1px solid var(--crimson);
  opacity: 0.5;
  transition: var(--transition);
}

.artist-card:hover {
  border-color: rgba(201, 168, 76, 0.5);
  box-shadow: 0 0 30px rgba(139, 0, 0, 0.3), 0 0 10px rgba(201, 168, 76, 0.1);
  transform: translateY(-3px);
}

.artist-card:hover::before {
  width: 50px;
  height: 50px;
  opacity: 1;
}

.artist-card:hover::after {
  width: 50px;
  height: 50px;
  opacity: 0.8;
}

/* ---- Artist Name ---- */
.artist-name {
  font-family: var(--font-en);
  font-size: clamp(0.85rem, 2.2vw, 1rem);
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--gold);
  margin-bottom: 0.8rem;
  padding-bottom: 0.6rem;
  border-bottom: 1px solid rgba(201, 168, 76, 0.2);
}

/* ---- Song List ---- */
.song-list {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.song-list li {
  font-family: var(--font-ja);
  font-size: clamp(0.82rem, 2vw, 0.92rem);
  font-weight: 300;
  color: rgba(240, 234, 214, 0.8);
  padding-left: 1em;
  position: relative;
  transition: color var(--transition);
}

.song-list li::before {
  content: '›';
  position: absolute;
  left: 0;
  color: var(--crimson);
  font-size: 0.8em;
  top: 0.1em;
}

.song-list li:hover {
  color: var(--white);
}

/* =========================================================
   SNS SECTION
   ========================================================= */

.sns {
  padding: 5rem 0;
  background: var(--black);
  position: relative;
}

.sns::before {
  content: '';
  display: block;
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 1px;
  background: linear-gradient(to right, transparent, var(--gold), transparent);
}

/* Grid: allows easy addition of new buttons */
.sns-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: center;
  align-items: center;
}

/* Base SNS button */
.sns-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.9em 2em;
  font-family: var(--font-en);
  font-size: 0.9rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  border: 1px solid rgba(201, 168, 76, 0.4);
  background: rgba(26, 26, 26, 0.8);
  color: var(--white);
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.sns-btn::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, var(--crimson), #5a0000);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition);
  z-index: 0;
}

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

.sns-btn:hover {
  border-color: var(--crimson);
  color: var(--white);
  box-shadow: 0 0 20px rgba(139, 0, 0, 0.5);
}

.sns-btn:hover::before {
  transform: scaleX(1);
}

.sns-btn__icon {
  font-size: 1.1em;
  line-height: 1;
}

/* X-specific styling */
.sns-btn--x .sns-btn__icon {
  font-family: var(--font-en);
  font-weight: 900;
  color: var(--gold);
}

/* =========================================================
   FOOTER
   ========================================================= */

.footer {
  background: var(--charcoal);
  border-top: 1px solid rgba(201, 168, 76, 0.1);
  padding: 2rem 1.5rem;
  text-align: center;
}

.footer__copy {
  font-family: var(--font-en);
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  color: var(--muted);
}

/* =========================================================
   SCROLL REVEAL (JS adds .is-visible)
   ========================================================= */

.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* =========================================================
   RESPONSIVE
   ========================================================= */

/* Mobile first — most rules already are.
   Adjust some things for larger screens. */

@media (max-width: 480px) {
  .song-grid {
    grid-template-columns: 1fr;
  }

  .hero__title-en {
    font-size: clamp(3.5rem, 20vw, 5rem);
  }

  .hero__image-wrap {
    width: 180px;
  }

  .hero__catch::before,
  .hero__catch::after {
    display: none;
  }
}

@media (min-width: 769px) {
  .song-grid {
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  }
}

@media (min-width: 1200px) {
  .song-grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

/* =========================================================
   SCROLLBAR
   ========================================================= */

::-webkit-scrollbar {
  width: 6px;
}

::-webkit-scrollbar-track {
  background: var(--black);
}

::-webkit-scrollbar-thumb {
  background: var(--crimson);
  border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--gold);
}