:root {
  color-scheme: light dark;
  --bg: #f4f5f8;
  --card-bg: #ffffff;
  --text: #1b1d22;
  --text-muted: #767a85;
  --border: #e4e6eb;
  --accent: #4f6bff;
  --accent-dark: #3b53e0;
  --bubble-mine: #4f6bff;
  --bubble-mine-text: #ffffff;
  --bubble-theirs: #ffffff;
  --bubble-theirs-text: #1b1d22;
  --danger: #e5484d;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14151a;
    --card-bg: #1e2028;
    --text: #eef0f5;
    --text-muted: #9298a8;
    --border: #2b2e38;
    --bubble-mine: #4f6bff;
    --bubble-mine-text: #ffffff;
    --bubble-theirs: #2a2d38;
    --bubble-theirs-text: #eef0f5;
  }
}

* { box-sizing: border-box; }

html, body {
  height: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo",
    "Segoe UI", "Malgun Gothic", Roboto, Helvetica, Arial, sans-serif;
}

.app {
  height: 100vh;
  height: 100dvh;
  display: flex;
  flex-direction: column;
}

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

.hidden {
  display: none !important;
}

/* ---------- Join screen ---------- */

#join-screen {
  align-items: center;
  justify-content: center;
  padding: 24px;
  background: radial-gradient(circle at top, rgba(79, 107, 255, 0.12), transparent 60%), var(--bg);
}

.join-card {
  width: 100%;
  max-width: 380px;
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 32px 28px;
  box-shadow: 0 20px 40px -20px rgba(20, 20, 40, 0.25);
}

.join-card h1 {
  margin: 0 0 6px;
  font-size: 24px;
}

.subtitle {
  margin: 0 0 24px;
  color: var(--text-muted);
  font-size: 14px;
  line-height: 1.5;
}

.field {
  display: block;
  margin-bottom: 16px;
}

.field span {
  display: block;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-muted);
  margin-bottom: 6px;
}

.field span small {
  font-weight: 400;
  color: var(--text-muted);
}

.field input[type="text"],
.field select {
  width: 100%;
  padding: 12px 14px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--text);
  font-size: 15px;
  outline: none;
  transition: border-color 0.15s ease;
  font-family: inherit;
}

.field input[type="text"]:focus,
.field select:focus {
  border-color: var(--accent);
}

.room-row {
  display: flex;
  gap: 8px;
}

.room-row input {
  flex: 1;
  min-width: 0;
}

.primary-btn {
  width: 100%;
  padding: 13px 16px;
  border: none;
  border-radius: 12px;
  background: var(--accent);
  color: #fff;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s ease, opacity 0.15s ease;
}

.primary-btn:hover:not(:disabled) {
  background: var(--accent-dark);
}

.primary-btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.ghost-btn {
  border: 1px solid var(--border);
  background: var(--card-bg);
  color: var(--text);
  border-radius: 12px;
  padding: 10px 14px;
  font-size: 14px;
  cursor: pointer;
  white-space: nowrap;
  transition: background 0.15s ease;
}

.ghost-btn:hover {
  background: var(--bg);
}

.ghost-btn.danger {
  color: var(--danger);
  border-color: rgba(229, 72, 77, 0.35);
}

.error-text {
  min-height: 18px;
  margin: 12px 0 0;
  color: var(--danger);
  font-size: 13px;
  text-align: center;
}

/* ---------- Chat screen ---------- */

.chat-header {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 14px 18px;
  background: var(--card-bg);
  border-bottom: 1px solid var(--border);
  flex-wrap: wrap;
}

.chat-header-info {
  display: flex;
  flex-direction: column;
  gap: 4px;
  min-width: 0;
}

.room-badge {
  display: flex;
  align-items: baseline;
  gap: 6px;
  font-weight: 700;
  font-size: 15px;
}

.room-label {
  font-size: 11px;
  font-weight: 600;
  color: var(--text-muted);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 1px 6px;
}

#room-code-display {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  max-width: 220px;
}

.presence-status {
  align-self: flex-start;
  font-size: 12px;
  color: var(--text-muted);
  background: none;
  border: none;
  padding: 0;
  cursor: pointer;
  text-decoration: underline dotted;
  text-underline-offset: 2px;
}

.presence-status.online {
  color: #17a34a;
}

.member-panel {
  position: absolute;
  top: calc(100% + 6px);
  left: 18px;
  z-index: 10;
  min-width: 180px;
  max-width: 260px;
  max-height: 240px;
  overflow-y: auto;
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 12px;
  box-shadow: 0 12px 28px -12px rgba(20, 20, 40, 0.35);
  padding: 8px;
}

.member-panel-title {
  font-size: 11px;
  font-weight: 700;
  color: var(--text-muted);
  padding: 4px 8px 6px;
}

.member-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 8px;
  border-radius: 8px;
  font-size: 13px;
}

.member-item:hover {
  background: var(--bg);
}

.member-item .member-you {
  color: var(--text-muted);
  font-size: 11px;
}

.chat-header-actions {
  display: flex;
  gap: 8px;
}

.messages {
  flex: 1;
  overflow-y: auto;
  padding: 18px 16px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.msg-row {
  display: flex;
  flex-direction: column;
  max-width: 76%;
}

.msg-row.mine {
  align-self: flex-end;
  align-items: flex-end;
}

.msg-row.theirs {
  align-self: flex-start;
  align-items: flex-start;
}

.msg-with-avatar {
  display: flex;
  align-items: flex-start;
  gap: 8px;
}

.avatar {
  flex-shrink: 0;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  font-weight: 700;
  color: #fff;
}

.msg-content {
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.msg-nickname {
  font-size: 11px;
  color: var(--text-muted);
  margin: 0 4px 3px;
}

.msg-bubble-wrap {
  display: flex;
  align-items: flex-end;
  gap: 6px;
}

.msg-row.mine .msg-bubble-wrap {
  flex-direction: row-reverse;
}

.msg-bubble {
  padding: 10px 14px;
  border-radius: 18px;
  font-size: 14.5px;
  line-height: 1.45;
  word-break: break-word;
  white-space: pre-wrap;
  box-shadow: 0 1px 1px rgba(0,0,0,0.04);
}

.msg-row.mine .msg-bubble {
  background: var(--bubble-mine);
  color: var(--bubble-mine-text);
  border-bottom-right-radius: 4px;
}

.msg-row.theirs .msg-bubble {
  background: var(--bubble-theirs);
  color: var(--bubble-theirs-text);
  border: 1px solid var(--border);
  border-bottom-left-radius: 4px;
}

.msg-time {
  font-size: 10.5px;
  color: var(--text-muted);
  white-space: nowrap;
  margin-bottom: 2px;
}

.msg-system {
  align-self: center;
  color: var(--text-muted);
  font-size: 12px;
  background: transparent;
  padding: 4px 10px;
  text-align: center;
}

.typing-indicator {
  padding: 0 18px 6px;
  font-size: 12px;
  color: var(--text-muted);
  font-style: italic;
}

.message-form {
  display: flex;
  gap: 10px;
  padding: 14px 16px;
  background: var(--card-bg);
  border-top: 1px solid var(--border);
}

.message-form input {
  flex: 1;
  min-width: 0;
  padding: 12px 14px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--text);
  font-size: 15px;
  outline: none;
}

.message-form input:focus {
  border-color: var(--accent);
}

.message-form .primary-btn {
  width: auto;
  padding: 12px 20px;
}

@media (max-width: 480px) {
  .msg-row {
    max-width: 88%;
  }
  .chat-header {
    padding: 12px 14px;
  }
}