/* ── Tokens ── */
:root {
  --color-bg: #0E1418;
  --color-amber: #E8A04A;
  --color-mist: #C4D4C8;
  --color-steel: #6B7C86;
  --color-shock: #FF6B3D;
  --color-surface: rgba(196, 212, 200, 0.06);

  --font-display: 'Dela Gothic One', sans-serif;
  --font-body: 'Zen Kaku Gothic New', sans-serif;

  --ring-size: min(72vw, 320px);
  --ring-stroke: 3px;
  --zazen-size: 44%;
  --zazen-opacity: 0.09;
  --zazen-opacity-peak: 0.15;
  --transition-screen: 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ── Fonts (self-hosted) ── */
@font-face {
  font-family: 'Dela Gothic One';
  src: url('../fonts/DelaGothicOne-Regular.ttf') format('truetype');
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: 'Zen Kaku Gothic New';
  src: url('../fonts/ZenKakuGothicNew-Regular.ttf') format('truetype');
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: 'Zen Kaku Gothic New';
  src: url('../fonts/ZenKakuGothicNew-Medium.ttf') format('truetype');
  font-weight: 500;
  font-style: normal;
  font-display: swap;
}

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

html, body {
  height: 100%;
  height: 100dvh;
  overflow: hidden;
}

body {
  font-family: var(--font-body);
  font-weight: 400;
  background: var(--color-bg);
  color: var(--color-mist);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ── Header ── */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.25rem;
  padding-top: max(1rem, env(safe-area-inset-top));
  pointer-events: none;
}

.site-title {
  font-family: var(--font-display);
  font-size: 0.7rem;
  letter-spacing: 0.04em;
  color: var(--color-steel);
  opacity: 0.6;
}

.btn-why {
  pointer-events: auto;
  font-family: var(--font-body);
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--color-steel);
  background: transparent;
  border: 1px solid rgba(107, 124, 134, 0.35);
  border-radius: 999px;
  padding: 0.35rem 0.85rem;
  cursor: pointer;
  transition: color 0.2s, border-color 0.2s, background 0.2s;
}

.btn-why:hover,
.btn-why:focus-visible {
  color: var(--color-mist);
  border-color: var(--color-amber);
  background: rgba(232, 160, 74, 0.08);
  outline: none;
}

/* ── Screens ── */
#app {
  position: relative;
  width: 100%;
  height: 100%;
  height: 100vh; /* fallback for browsers without dvh */
  height: 100dvh;
  container-type: size;
  container-name: app;
}

.screen {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  opacity: 1;
  transition: opacity var(--transition-screen);
}

.screen[hidden] {
  display: none;
  opacity: 0;
  pointer-events: none;
}

/* ── Gate ── */
.screen--gate {
  cursor: pointer;
}

.gate-content {
  text-align: center;
  pointer-events: none;
  user-select: none;
}

.gate-title {
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 6vw, 2.4rem);
  color: var(--color-mist);
  letter-spacing: 0.02em;
  margin-bottom: 2rem;
}

.gate-hint {
  font-size: 1rem;
  font-weight: 500;
  color: var(--color-amber);
  margin-bottom: 0.75rem;
  animation: pulse-hint 2.4s ease-in-out infinite;
}

.gate-sub {
  font-size: 0.8rem;
  color: var(--color-steel);
  letter-spacing: 0.08em;
}

.gate-tap {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  background: transparent;
  border: none;
  cursor: pointer;
  z-index: 1;
}

.gate-tap:focus-visible {
  outline: 2px solid var(--color-amber);
  outline-offset: -4px;
}

@keyframes pulse-hint {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.45; }
}

/* ── 人数表示 ── */
/* 出ていない間も高さを確保して、数字が届いた瞬間にレイアウトがずれないようにする。 */
.presence {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.45rem;
  min-height: 1.15rem;
  margin-top: 1.5rem;
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  color: var(--color-steel);
  opacity: 0;
  transition: opacity 0.8s ease;
}

.presence.is-visible {
  opacity: 0.85;
}

.presence[data-tier='live'] {
  color: var(--color-mist);
}

.presence[data-tier='live']::before {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-amber);
  box-shadow: 0 0 6px rgba(232, 160, 74, 0.6);
  animation: presence-blink 3s ease-in-out infinite;
}

@keyframes presence-blink {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.3; }
}

.screen--done .presence {
  margin-top: 0.25rem;
}

/* ── Session ── */
.screen--session {
  gap: 1.5rem;
  /* Keep the centered ring/copy from sitting on the bottom links. */
  padding-bottom: calc(4.5rem + env(safe-area-inset-bottom, 0px));
}

.mach-ring {
  position: relative;
  width: var(--ring-size);
  height: var(--ring-size);
}

.mach-ring__svg {
  width: 100%;
  height: 100%;
  transform: rotate(-90deg);
}

.mach-ring__figure {
  position: absolute;
  top: 50%;
  left: 50%;
  width: var(--zazen-size);
  height: var(--zazen-size);
  fill: var(--color-mist);
  opacity: var(--zazen-opacity);
  transform: translate(-50%, -50%);
  animation: zazen-breath 10s ease-in-out infinite;
  pointer-events: none;
}

@keyframes zazen-breath {
  0%, 100% {
    opacity: var(--zazen-opacity);
    transform: translate(-50%, -50%) scale(1);
  }
  50% {
    opacity: var(--zazen-opacity-peak);
    transform: translate(-50%, -50%) scale(1.035);
  }
}

.mach-ring__track {
  stroke: rgba(107, 124, 134, 0.2);
  stroke-width: var(--ring-stroke);
}

.mach-ring__progress {
  stroke: var(--color-amber);
  stroke-width: var(--ring-stroke);
  stroke-linecap: round;
  stroke-dasharray: 553;
  stroke-dashoffset: 553;
  transition: stroke-dashoffset 0.3s linear;
  filter: drop-shadow(0 0 6px rgba(232, 160, 74, 0.4));
}

.mach-ring__shockwave {
  position: absolute;
  inset: 0;
  border-radius: 50%;
  border: 2px solid var(--color-shock);
  opacity: 0;
  transform: scale(0.6);
  pointer-events: none;
}

.mach-ring--shock .mach-ring__shockwave {
  animation: shockwave 0.7s cubic-bezier(0.2, 0.8, 0.3, 1) forwards;
}

@keyframes shockwave {
  0% {
    opacity: 0.9;
    transform: scale(0.6);
    border-color: var(--color-shock);
  }
  100% {
    opacity: 0;
    transform: scale(1.5);
    border-color: var(--color-amber);
  }
}

.session-time {
  font-family: var(--font-display);
  font-size: clamp(2rem, 8vw, 3rem);
  color: var(--color-mist);
  letter-spacing: 0.06em;
  font-variant-numeric: tabular-nums;
}

.session-label {
  font-size: 0.85rem;
  color: var(--color-steel);
  letter-spacing: 0.12em;
}

.session-aside {
  position: absolute;
  right: 0;
  bottom: 0;
  z-index: 2;
  display: flex;
  gap: 0.6rem;
  padding: 1rem 1.25rem;
  padding-right: max(1.25rem, env(safe-area-inset-right));
  padding-bottom: max(1rem, env(safe-area-inset-bottom));
}

@media (max-width: 640px) {
  .session-aside {
    left: 0;
    right: 0;
    justify-content: center;
    flex-wrap: wrap;
    padding-left: max(1rem, env(safe-area-inset-left));
    padding-right: max(1rem, env(safe-area-inset-right));
  }
}

@media (max-height: 700px) {
  :root {
    --ring-size: min(58vw, 260px);
  }

  .screen--session {
    gap: 1rem;
  }
}

@media (max-height: 520px) {
  :root {
    --ring-size: min(42vw, 180px);
  }
}

/* Same breakpoints against #app itself, so device-emulation / split views still match. */
@container app (max-width: 640px) {
  .session-aside {
    left: 0;
    right: 0;
    justify-content: center;
    flex-wrap: wrap;
    padding-left: max(1rem, env(safe-area-inset-left));
    padding-right: max(1rem, env(safe-area-inset-right));
  }
}

@container app (max-height: 700px) {
  .screen--session {
    --ring-size: min(58cqw, 260px);
    gap: 1rem;
  }
}

@container app (max-height: 520px) {
  .screen--session {
    --ring-size: min(42cqw, 180px);
  }
}

/* Same pill as .btn-why, so these read as controls rather than stray text. */
.session-aside__link {
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  color: var(--color-steel);
  text-decoration: none;
  border: 1px solid rgba(107, 124, 134, 0.35);
  border-radius: 999px;
  padding: 0.35rem 0.85rem;
  opacity: 0.75;
  transition: opacity 0.3s, color 0.3s, border-color 0.3s, background 0.3s;
}

.session-aside__link--tip {
  color: var(--color-amber);
  border-color: rgba(232, 160, 74, 0.4);
  opacity: 0.9;
}

.session-aside__link:hover,
.session-aside__link:focus-visible {
  opacity: 1;
  color: var(--color-mist);
  border-color: var(--color-amber);
  background: rgba(232, 160, 74, 0.08);
  outline: none;
}

/* ── Done ── */
.screen--done {
  gap: 1.25rem;
  padding: 2rem;
  text-align: center;
}

.done-title {
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 5vw, 2rem);
  color: var(--color-mist);
}

.done-lead {
  font-size: 0.95rem;
  color: var(--color-steel);
  margin-bottom: 0.5rem;
}

.done-links {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  margin: 1rem 0;
}

.done-link {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-amber);
  text-decoration: none;
  padding: 0.6rem 1.5rem;
  border: 1px solid rgba(232, 160, 74, 0.4);
  border-radius: 999px;
  transition: background 0.2s, border-color 0.2s;
}

.done-link:hover,
.done-link:focus-visible {
  background: rgba(232, 160, 74, 0.1);
  border-color: var(--color-amber);
  outline: none;
}

.done-link--subtle {
  font-weight: 400;
  font-size: 0.8rem;
  color: var(--color-steel);
  border-color: rgba(107, 124, 134, 0.3);
}

.done-link--subtle:hover,
.done-link--subtle:focus-visible {
  color: var(--color-mist);
  background: rgba(107, 124, 134, 0.1);
  border-color: var(--color-steel);
}

.btn-restart {
  font-family: var(--font-body);
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-mist);
  background: var(--color-surface);
  border: 1px solid rgba(196, 212, 200, 0.15);
  border-radius: 999px;
  padding: 0.75rem 2rem;
  cursor: pointer;
  margin-top: 0.5rem;
  transition: background 0.2s, border-color 0.2s;
}

.btn-restart:hover,
.btn-restart:focus-visible {
  background: rgba(196, 212, 200, 0.12);
  border-color: rgba(196, 212, 200, 0.3);
  outline: none;
}

/* ── Concept modal ── */
.concept-modal {
  border: none;
  padding: 0;
  background: transparent;
  max-width: min(90vw, 480px);
  width: 100%;
  margin: auto;
  max-height: 88dvh;
  overflow-y: auto;
  overscroll-behavior: contain;
}

.concept-modal::backdrop {
  background: rgba(14, 20, 24, 0.85);
  backdrop-filter: blur(4px);
}

.concept-modal__inner {
  background: #151c22;
  border: 1px solid rgba(107, 124, 134, 0.25);
  border-radius: 12px;
  padding: 1.75rem;
  color: var(--color-mist);
}

.concept-modal__title {
  font-family: var(--font-display);
  font-size: 1.1rem;
  margin-bottom: 1.25rem;
  color: var(--color-amber);
}

.concept-modal__body {
  font-size: 0.9rem;
  line-height: 1.75;
  color: rgba(196, 212, 200, 0.85);
}

.concept-modal__body p {
  margin-bottom: 0.85rem;
}

.concept-modal__body p:last-child {
  margin-bottom: 0;
}

.concept-modal__body strong {
  color: var(--color-mist);
  font-weight: 500;
}

.concept-modal__tip {
  margin-top: 1.25rem;
  padding-top: 1rem;
  border-top: 1px solid rgba(107, 124, 134, 0.2);
  color: var(--color-amber);
  font-weight: 500;
}

.concept-modal__close {
  display: block;
  width: 100%;
  margin-top: 1.5rem;
  font-family: var(--font-body);
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--color-steel);
  background: transparent;
  border: 1px solid rgba(107, 124, 134, 0.3);
  border-radius: 999px;
  padding: 0.65rem;
  cursor: pointer;
  transition: color 0.2s, border-color 0.2s;
}

.concept-modal__close:hover,
.concept-modal__close:focus-visible {
  color: var(--color-mist);
  border-color: var(--color-steel);
  outline: none;
}

/* ── Reduced motion ── */
@media (prefers-reduced-motion: reduce) {
  .gate-hint {
    animation: none;
  }

  .presence[data-tier='live']::before {
    animation: none;
  }

  .mach-ring--shock .mach-ring__shockwave {
    animation: none;
    opacity: 0;
  }

  .mach-ring__progress {
    transition: none;
  }

  .mach-ring__figure {
    animation: none;
  }

  .screen {
    transition: none;
  }
}