.ring-welcome, .phase-briefing {
  position: absolute;
  color: #f5f7ff;
  font-family: 'Segoe UI Variable Display', 'Segoe UI', system-ui, sans-serif;
}
.ring-welcome[hidden], .phase-briefing[hidden] { display: none; }
.ring-welcome {
  left: 50%; top: 50%; width: min(80vw, 600px);
  transform: translate(-50%, -50%);
  text-align: center;
}
.ring-welcome h2 { margin: 0 0 14px; font-size: clamp(28px, 4vw, 48px); font-weight: 300; letter-spacing: -.035em; }
.ring-welcome p { margin: 0; font-size: clamp(14px, 1.6vw, 20px); color: #e0e6f1; }
.phase-briefing {
  --header-height: 100px;
  --header-shadow: 0 8px 32px #11183012;
  top: clamp(110px, 20vh, 200px);
  bottom: 120px;
  left: 50%;
  width: min(660px, calc(100vw - 48px));
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
}
.briefing-phase-title {
  margin: 0 0 28px;
  text-align: center;
  font-size: clamp(21px, 2.1vw, 30px);
  font-weight: 350;
  line-height: 1.25;
  letter-spacing: .04em;
  overflow-wrap: anywhere;
  animation: briefing-arrive var(--motion-title) ease both;
}
.briefing-card { position: relative; flex: 1; min-height: 160px; }
.briefing-header {
  height: var(--header-height);
  position: relative;
  z-index: 1;
  border-radius: 18px 18px 0 0;
  background: #e9f3ff16;
  border: 1px solid #edf6ff35;
  backdrop-filter: blur(22px);
  box-shadow: var(--header-shadow);
  animation: header-arrive var(--motion-header) var(--motion-headerDelay) both;
}
.briefing-number {
  position: absolute; top: 24px; left: 28px;
  width: 50px; height: 50px;
  display: grid; place-items: center;
  border: 1px solid #edf6ff65;
  border-radius: 50%;
  background: transparent;
  font-size: 21px; font-weight: 300;
  animation: number-slide var(--motion-number) cubic-bezier(.22,.7,.25,1) both;
}
.briefing-heading { padding: 23px 24px 18px 100px; animation: briefing-write var(--motion-heading) var(--motion-headingDelay) both; }
.briefing-heading h3 { margin: 0 0 5px; font-size: 23px; font-weight: 500; letter-spacing: -.025em; }
.briefing-heading p { margin: 0; font-size: 14px; color: #e2e8f2; }
.briefing-body {
  position: absolute; inset: var(--header-height) 0 0;
  border: 1px solid #edf6ff28; border-top: 0;
  border-radius: 0 0 18px 18px;
  background: linear-gradient(160deg, #0b162b22, #16223812);
  backdrop-filter: blur(16px);
  transform-origin: top;
  animation: briefing-expand var(--motion-body) var(--motion-bodyDelay) cubic-bezier(.2,.7,.2,1) both;
}
@keyframes briefing-arrive { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: none; } }
@keyframes header-arrive { from { background: transparent; border-color: transparent; backdrop-filter: blur(0); } }
@keyframes number-slide {
  0%, 30% { left: calc(50% - 25px); opacity: 0; }
  45% { left: calc(50% - 25px); opacity: 1; }
  100% { left: var(--number-left, 28px); opacity: 1; }
}
@keyframes briefing-write { from { clip-path: inset(0 100% 0 0); opacity: 0; } to { clip-path: inset(0); opacity: 1; } }
@keyframes briefing-expand { from { transform: scaleY(0); opacity: 0; } to { transform: scaleY(1); opacity: 1; } }
@media (max-height: 600px) {
  .phase-briefing { top: 90px; bottom: 100px; --header-height: 88px; }
  .briefing-phase-title { margin-bottom: 12px; }
  .briefing-number { top: 18px; }
  .briefing-heading { padding-top: 17px; }
}
@media (prefers-reduced-motion: reduce) {
  .phase-briefing *, .ring-welcome { animation: none; }
}