:root {
  --bg: #eef3f7;
  --bg-accent: radial-gradient(circle at top left, rgba(55, 108, 255, 0.12), transparent 34%),
    radial-gradient(circle at bottom right, rgba(0, 143, 117, 0.1), transparent 28%);
  --panel: rgba(255, 255, 255, 0.86);
  --panel-strong: rgba(255, 255, 255, 0.96);
  --line: rgba(15, 23, 42, 0.08);
  --text: #102033;
  --muted: #5f6f81;
  --brand: #2459d3;
  --brand-strong: #1a48b4;
  --brand-soft: rgba(36, 89, 211, 0.1);
  --ok: #128365;
  --warn: #b4541d;
  --shadow: 0 24px 60px rgba(12, 28, 55, 0.12);
  --shadow-soft: 0 14px 30px rgba(12, 28, 55, 0.09);
  --radius-xl: 28px;
  --radius-lg: 22px;
  --radius-md: 16px;
  --radius-sm: 12px;
}

* {
  box-sizing: border-box;
}

html {
  height: 100%;
}

body {
  margin: 0;
  min-height: 100%;
  font-family: "Manrope", "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--text);
  background: var(--bg-accent), linear-gradient(180deg, #f7fafc 0%, var(--bg) 100%);
}

a {
  color: inherit;
}

button,
input,
textarea {
  font: inherit;
}

.landing-shell,
.room-shell {
  min-height: 100vh;
  padding: 28px;
}

.landing-shell {
  display: grid;
  place-items: center;
}

.hero-card,
.room-panel {
  width: min(1120px, 100%);
  border: 1px solid rgba(255, 255, 255, 0.72);
  border-radius: var(--radius-xl);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.92), rgba(255, 255, 255, 0.72));
  box-shadow: var(--shadow);
  backdrop-filter: blur(16px);
}

.hero-card {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 28px;
  padding: 36px;
}

.hero-copy {
  padding: 10px 6px 10px 6px;
}

.eyebrow,
.brand-mark {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: "JetBrains Mono", monospace;
  font-size: 0.9rem;
  color: var(--brand);
  letter-spacing: 0.04em;
  text-decoration: none;
}

.hero-copy h1 {
  margin: 16px 0 14px;
  font-size: clamp(2.4rem, 5vw, 4.2rem);
  line-height: 0.98;
  letter-spacing: -0.05em;
}

.hero-copy p {
  max-width: 540px;
  margin: 0;
  color: var(--muted);
  font-size: 1.04rem;
  line-height: 1.75;
}

.panel-card {
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: var(--panel-strong);
  box-shadow: var(--shadow-soft);
}

.form-panel {
  padding: 24px;
}

.stack-form {
  display: grid;
  gap: 16px;
}

.field {
  display: grid;
  gap: 10px;
}

.field-label {
  font-size: 0.95rem;
  color: var(--muted);
}

.field input,
.composer textarea {
  width: 100%;
  border: 1px solid rgba(16, 32, 51, 0.1);
  border-radius: 18px;
  background: #ffffff;
  color: var(--text);
  padding: 15px 16px;
  outline: none;
  transition: border-color 0.16s ease, box-shadow 0.16s ease, transform 0.16s ease;
}

.field input:focus,
.composer textarea:focus {
  border-color: rgba(36, 89, 211, 0.4);
  box-shadow: 0 0 0 4px rgba(36, 89, 211, 0.11);
}

.action-row,
.composer-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.btn {
  border: 0;
  border-radius: 14px;
  padding: 13px 18px;
  font-weight: 700;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.15s ease, opacity 0.15s ease;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
}

.btn-primary {
  background: linear-gradient(180deg, var(--brand), var(--brand-strong));
  color: #fff;
  box-shadow: 0 12px 24px rgba(36, 89, 211, 0.24);
}

.btn-secondary {
  background: rgba(16, 32, 51, 0.06);
  color: var(--text);
}

.form-error {
  border-radius: 14px;
  background: rgba(180, 84, 29, 0.08);
  color: var(--warn);
  padding: 12px 14px;
  font-size: 0.95rem;
}

.tips-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin-top: 20px;
}

.tip-card {
  display: grid;
  gap: 6px;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: linear-gradient(180deg, rgba(248, 250, 252, 0.85), rgba(255, 255, 255, 0.92));
}

.tip-card strong {
  font-size: 0.98rem;
}

.tip-card span {
  color: var(--muted);
  font-size: 0.93rem;
  line-height: 1.55;
}

.room-panel {
  margin: 0 auto;
  padding: 22px;
  display: grid;
  gap: 18px;
}

.room-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 16px;
  padding: 6px 6px 0;
}

.room-title {
  display: flex;
  align-items: flex-start;
  gap: 16px;
}

.room-title h1 {
  margin: 0;
  font-size: clamp(1.7rem, 3vw, 2.4rem);
  letter-spacing: -0.04em;
}

.room-title p {
  margin: 8px 0 0;
  color: var(--muted);
}

.room-meta {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.meta-pill {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-height: 46px;
  padding: 10px 14px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.92);
}

.meta-label {
  color: var(--muted);
  font-size: 0.92rem;
}

#connection-status[data-state="connected"] {
  color: var(--ok);
  border-color: rgba(18, 131, 101, 0.18);
  background: rgba(18, 131, 101, 0.08);
}

#connection-status[data-state="connecting"] {
  color: var(--brand);
  border-color: rgba(36, 89, 211, 0.15);
  background: rgba(36, 89, 211, 0.08);
}

#connection-status[data-state="disconnected"] {
  color: var(--warn);
  border-color: rgba(180, 84, 29, 0.18);
  background: rgba(180, 84, 29, 0.09);
}

.chat-stage {
  position: relative;
  min-height: 62vh;
  border: 1px solid var(--line);
  border-radius: 26px;
  background: linear-gradient(180deg, rgba(249, 251, 253, 0.98), rgba(242, 246, 249, 0.95));
  overflow: hidden;
}

.chat-stage.is-dragging {
  border-color: rgba(36, 89, 211, 0.3);
  box-shadow: inset 0 0 0 2px rgba(36, 89, 211, 0.12);
}

.message-stream {
  height: 62vh;
  overflow-y: auto;
  padding: 22px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.drop-hint {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  background: rgba(36, 89, 211, 0.08);
  color: var(--brand);
  font-weight: 700;
  letter-spacing: 0.02em;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.16s ease;
}

.chat-stage.is-dragging .drop-hint {
  opacity: 1;
}

.empty-state {
  margin: auto;
  width: min(420px, 100%);
  text-align: center;
  color: var(--muted);
  padding: 18px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.72);
  border: 1px dashed rgba(16, 32, 51, 0.12);
}

.message-item {
  display: flex;
}

.message-item.self {
  justify-content: flex-end;
}

.message-card {
  width: min(100%, 760px);
  padding: 14px;
  border-radius: 20px;
  border: 1px solid rgba(16, 32, 51, 0.08);
  background: rgba(255, 255, 255, 0.96);
  box-shadow: 0 12px 24px rgba(12, 28, 55, 0.05);
}

.message-item.self .message-card {
  background: linear-gradient(180deg, rgba(36, 89, 211, 0.95), rgba(26, 72, 180, 0.97));
  color: #fff;
}

.message-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 10px;
  font-size: 0.88rem;
}

.message-item.self .message-meta,
.message-item.self .file-hint,
.message-item.self .file-stats {
  color: rgba(255, 255, 255, 0.82);
}

.sender-name {
  font-weight: 800;
}

.message-time {
  color: var(--muted);
  white-space: nowrap;
}

.message-item.self .message-time {
  color: rgba(255, 255, 255, 0.76);
}

.bubble-text {
  margin: 0;
  white-space: pre-wrap;
  word-break: break-word;
  line-height: 1.68;
}

.file-card {
  display: grid;
  gap: 12px;
}

.file-preview-image {
  width: 100%;
  max-height: 340px;
  border-radius: 18px;
  object-fit: cover;
  display: block;
  background: rgba(15, 23, 42, 0.04);
}

.file-preview-text {
  margin: 0;
  padding: 14px;
  border-radius: 16px;
  overflow: auto;
  font-family: "JetBrains Mono", monospace;
  font-size: 0.84rem;
  line-height: 1.65;
  background: rgba(15, 23, 42, 0.06);
  color: inherit;
  max-height: 300px;
}

.file-card audio,
.file-card video {
  width: 100%;
  border-radius: 16px;
  background: rgba(15, 23, 42, 0.9);
}

.file-hint {
  font-size: 0.94rem;
  color: var(--muted);
}

.file-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

.file-name {
  font-weight: 700;
  word-break: break-word;
}

.file-stats {
  color: var(--muted);
  font-size: 0.92rem;
}

.file-actions {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.inline-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 38px;
  padding: 0 14px;
  border-radius: 999px;
  text-decoration: none;
  font-weight: 700;
  background: rgba(16, 32, 51, 0.08);
  color: inherit;
}

.message-item.self .inline-link {
  background: rgba(255, 255, 255, 0.14);
}

.composer {
  display: grid;
  gap: 12px;
  padding: 12px;
  border-radius: 24px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.92);
}

.composer textarea {
  resize: none;
  min-height: 62px;
  max-height: 180px;
  border-radius: 18px;
}

.room-footnote {
  padding: 0 8px 4px;
  color: var(--muted);
  font-size: 0.92rem;
}

@media (max-width: 920px) {
  .landing-shell,
  .room-shell {
    padding: 16px;
  }

  .hero-card {
    grid-template-columns: 1fr;
    padding: 20px;
  }

  .tips-grid {
    grid-template-columns: 1fr;
  }

  .room-header,
  .room-title {
    flex-direction: column;
  }

  .room-meta {
    justify-content: flex-start;
  }

  .message-stream,
  .chat-stage {
    height: 58vh;
    min-height: 58vh;
  }
}

@media (max-width: 640px) {
  .hero-copy h1 {
    font-size: 2.5rem;
  }

  .room-panel {
    padding: 14px;
    border-radius: 22px;
  }

  .message-stream {
    padding: 14px;
  }

  .message-card {
    width: 100%;
    padding: 12px;
    border-radius: 18px;
  }

  .composer {
    padding: 10px;
  }

  .composer-actions,
  .action-row {
    flex-direction: column;
  }

  .btn {
    width: 100%;
  }
}