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

:root {
  --bg:             #000000;
  --text:           #ffffff;
  --muted:          #9ca3af;
  --input-bg:       #1a1a1a;
  --border:         #374151;
  --border-focus:   #6b7280;
  --confirm-bg:     #374151;
  --confirm-active: #4b5563;
  --sos:            #cc2626;
  --sos-pressed:    #991c1c;
  --sos-success:    #16a34a;
  --banner-bg:      #7c2d12;
  --banner-text:    #fed7aa;
}

html, body {
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  -webkit-tap-highlight-color: transparent;
  overscroll-behavior: none;
  user-select: none;
}

body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  /* Use dynamic viewport height on mobile to account for browser chrome */
  min-height: 100dvh;
}

/* ===== Private mode banner (decision #1041) ===== */

.private-banner {
  background: var(--banner-bg);
  color: var(--banner-text);
  padding: 10px 16px;
  font-size: 13px;
  line-height: 1.5;
  text-align: center;
  flex-shrink: 0;
}

.private-banner[hidden] { display: none; }

/* ===== Top bar ===== */

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 20px;
  flex-shrink: 0;
}

.user-avatar {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: #374151;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 13px;
  font-weight: 600;
  color: var(--text);
  letter-spacing: 0;
}

.network-indicator {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--muted);
  transition: background 0.3s ease;
}

.network-indicator.online  { background: #16a34a; }
.network-indicator.offline { background: #4b5563; }

/* ===== Screens ===== */

.screen {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-height: 0;
}

.screen[hidden] { display: none; }

.screen-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 16px;
  padding: 24px 20px;
}

/* ===== Onboarding ===== */

.name-input {
  width: 100%;
  max-width: 320px;
  padding: 14px 16px;
  background: var(--input-bg);
  border: 1.5px solid var(--border);
  border-radius: 12px;
  color: var(--text);
  font-size: 17px;
  outline: none;
  transition: border-color 0.15s;
  -webkit-appearance: none;
  user-select: text;
}

.name-input::placeholder { color: var(--muted); }
.name-input:focus         { border-color: var(--border-focus); }

.btn-confirm {
  width: 100%;
  max-width: 320px;
  padding: 14px;
  background: var(--confirm-bg);
  border: none;
  border-radius: 12px;
  color: var(--text);
  font-size: 17px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s, opacity 0.15s;
}

.btn-confirm:disabled               { opacity: 0.35; cursor: default; }
.btn-confirm:not(:disabled):active  { background: var(--confirm-active); }

/* ===== SOS button (min 60vmin × 60vmin per UX spec) ===== */

.btn-sos {
  width: 60vmin;
  height: 60vmin;
  min-width: 180px;
  min-height: 180px;
  border-radius: 50%;
  border: none;
  background: var(--sos);
  color: #fff;
  font-size: clamp(24px, 9vmin, 60px);
  font-weight: 900;
  letter-spacing: 0.08em;
  cursor: pointer;
  touch-action: manipulation;
  transition: background 0.15s ease, transform 0.1s ease;
}

.btn-sos:active,
.btn-sos[data-state="sending"] {
  background: var(--sos-pressed);
  transform: scale(0.96);
}

.btn-sos[data-state="sending"] {
  animation: baton-pulse 1s ease-in-out infinite;
  cursor: default;
  pointer-events: none;
}

.btn-sos[data-state="success"] {
  background: var(--sos-success);
  transform: none;
}

@keyframes baton-pulse {
  0%, 100% { opacity: 1; }
  50%       { opacity: 0.55; }
}

/* ===== Status message ===== */

.status {
  padding: 12px 20px;
  text-align: center;
  font-size: 14px;
  flex-shrink: 0;
}

.status[hidden]    { display: none; }
.status--error     { color: #f87171; }
.status--success   { color: #4ade80; }