/* ── Variables ─────────────────────────────────────────────────── */
:root {
  --bg:           #12121e;
  --bg2:          #1a1a2e;
  --bg3:          #22223a;
  --surface:      #2a2a42;
  --surface2:     #323250;
  --accent:       #4361ee;
  --accent-hover: #3451d1;
  --accent-glow:  rgba(67, 97, 238, 0.25);
  --text:         #e8e8f0;
  --text-dim:     #8888aa;
  --text-muted:   #55556a;
  --success:      #2ecc71;
  --error:        #e74c3c;
  --border:       rgba(255,255,255,0.06);
  --radius:       14px;
  --radius-sm:    8px;
  --shadow:       0 8px 32px rgba(0,0,0,0.45);
  --transition:   all 0.2s ease;
}

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

html { font-size: 16px; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  min-height: 100vh;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

/* ── Scrollbar ─────────────────────────────────────────────────── */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--surface2); border-radius: 3px; }

/* ── Header ────────────────────────────────────────────────────── */
header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 24px;
  background: var(--bg2);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--text);
  letter-spacing: -0.02em;
}

.logo svg { color: var(--accent); flex-shrink: 0; }

.header-right { display: flex; align-items: center; gap: 10px; }

/* ── Buttons ─────────────────────────────────────────────────────── */
button { cursor: pointer; border: none; outline: none; transition: var(--transition); }

.btn-primary {
  background: var(--accent);
  color: #fff;
  font-weight: 600;
  font-size: 0.95rem;
  padding: 11px 22px;
  border-radius: var(--radius-sm);
}
.btn-primary:hover { background: var(--accent-hover); transform: translateY(-1px); box-shadow: 0 4px 16px var(--accent-glow); }
.btn-primary:active { transform: translateY(0); }
.btn-primary.full { width: 100%; }

.btn-ghost {
  background: transparent;
  color: var(--text-dim);
  font-size: 0.85rem;
  padding: 7px 14px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  gap: 6px;
}
.btn-ghost:hover { background: var(--surface); color: var(--text); border-color: rgba(255,255,255,0.12); }

.btn-sm {
  background: var(--surface);
  color: var(--text-dim);
  font-size: 0.78rem;
  padding: 5px 10px;
  border-radius: 6px;
  border: 1px solid var(--border);
}
.btn-sm:hover { background: var(--surface2); color: var(--text); }

/* ── Screens ─────────────────────────────────────────────────────── */
.screen { display: none; padding: 0 16px 32px; min-height: calc(100vh - 57px); }
.screen.active { display: block; }

/* ── Join Screen ─────────────────────────────────────────────────── */
.join-card {
  max-width: 420px;
  margin: 48px auto 0;
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 36px 32px;
  box-shadow: var(--shadow);
}

.join-card h1 {
  font-size: 1.6rem;
  font-weight: 800;
  letter-spacing: -0.04em;
  margin-bottom: 6px;
  background: linear-gradient(135deg, #fff 40%, var(--accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.subtitle { color: var(--text-dim); font-size: 0.9rem; margin-bottom: 28px; }

/* Mode tabs */
.mode-tabs {
  display: flex;
  background: var(--bg);
  border-radius: var(--radius-sm);
  padding: 4px;
  margin-bottom: 24px;
  gap: 4px;
}

.mode-tab {
  flex: 1;
  background: transparent;
  color: var(--text-dim);
  font-size: 0.88rem;
  font-weight: 600;
  padding: 9px;
  border-radius: 6px;
}
.mode-tab.active {
  background: var(--surface);
  color: var(--text);
  box-shadow: 0 2px 8px rgba(0,0,0,0.3);
}

/* Panels */
.panel { display: none; }
.panel.active { display: flex; flex-direction: column; gap: 14px; }

label { font-size: 0.82rem; font-weight: 600; color: var(--text-dim); letter-spacing: 0.04em; text-transform: uppercase; }

input[type="text"] {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text);
  font-size: 0.95rem;
  padding: 11px 14px;
  width: 100%;
  transition: var(--transition);
}
input[type="text"]:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-glow);
}
input[type="text"]::placeholder { color: var(--text-muted); }

/* Room code input – uppercase */
#joinCode { text-transform: uppercase; letter-spacing: 0.1em; font-size: 1.1rem; font-weight: 700; text-align: center; }

.error {
  color: var(--error);
  font-size: 0.82rem;
  text-align: center;
  padding: 8px;
  background: rgba(231,76,60,0.1);
  border-radius: var(--radius-sm);
}

/* ── Room Screen ─────────────────────────────────────────────────── */
#roomScreen { position: relative; }

/* Drop overlay */
.drop-overlay {
  position: fixed;
  inset: 0;
  background: rgba(18,18,30,0.88);
  backdrop-filter: blur(6px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 200;
}
.drop-overlay.hidden { display: none; }

.drop-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  color: var(--accent);
  border: 2px dashed var(--accent);
  border-radius: 20px;
  padding: 60px 80px;
  animation: pulse-border 1.2s ease-in-out infinite;
}
.drop-inner p { font-size: 1.2rem; font-weight: 700; color: var(--text); }

@keyframes pulse-border {
  0%, 100% { border-color: var(--accent); box-shadow: 0 0 0 0 var(--accent-glow); }
  50%       { border-color: #7b8fff; box-shadow: 0 0 0 16px transparent; }
}

/* Empty state */
.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 14px;
  min-height: calc(100vh - 130px);
  text-align: center;
  padding: 32px 16px;
}
.empty-state.hidden { display: none; }

.empty-icon {
  color: var(--text-muted);
  opacity: 0.5;
  margin-bottom: 8px;
}

.empty-state h2 { font-size: 1.5rem; font-weight: 700; letter-spacing: -0.03em; }
.empty-state p  { color: var(--text-dim); font-size: 0.9rem; line-height: 1.6; max-width: 380px; }

.room-code-display {
  display: flex;
  align-items: center;
  gap: 12px;
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 12px 20px;
  margin-top: 8px;
}

#bigRoomCode {
  font-size: 1.8rem;
  font-weight: 800;
  letter-spacing: 0.15em;
  font-family: 'SF Mono', 'Fira Code', monospace;
  color: var(--accent);
}

/* ── Peers Grid ──────────────────────────────────────────────────── */
.peers-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(480px, 1fr));
  gap: 16px;
  padding-top: 24px;
}
.peers-grid.hidden { display: none; }

/* ── Peer Card ───────────────────────────────────────────────────── */
.peer-card {
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  display: flex;
  flex-direction: row;
  align-items: flex-start;
  gap: 16px;
  cursor: pointer;
  transition: var(--transition);
  position: relative;
  user-select: none;
}
.peer-card:hover {
  background: var(--bg3);
  border-color: var(--accent);
  box-shadow: 0 8px 24px rgba(0,0,0,0.3), 0 0 0 1px var(--accent-glow);
}

/* Card layout containers */
.card-info {
  flex-shrink: 0;
  width: 100px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}
.card-sections {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

/* Mobile: full-width single-column grid */
@media (max-width: 600px) {
  .peers-grid {
    display: flex;
    flex-direction: column;
    gap: 12px;
  }
  .peer-card {
    padding: 12px;
    gap: 10px;
  }
  .card-info {
    width: 72px;
  }
  .card-info .peer-icon svg { width: 28px; height: 28px; }
  .card-info .peer-name { font-size: 0.78rem; text-align: center; }
  .card-info .peer-status { font-size: 0.65rem; }
  .card-sections { gap: 8px; }
  .peer-transfer-area { cursor: pointer; }
}
.peer-card.connected { border-color: var(--success); }
.peer-card.connected::after {
  content: '';
  position: absolute;
  top: 12px; right: 12px;
  width: 8px; height: 8px;
  border-radius: 50%;
  background: var(--success);
  box-shadow: 0 0 6px var(--success);
}
.peer-card.connecting { border-color: #f39c12; }
.peer-card.connecting::after {
  content: '';
  position: absolute;
  top: 12px; right: 12px;
  width: 8px; height: 8px;
  border-radius: 50%;
  background: #f39c12;
  animation: blink 1s ease infinite;
}
@keyframes blink { 0%,100% { opacity:1; } 50% { opacity:0.3; } }

.peer-icon { color: var(--text-dim); }
.peer-name { font-weight: 700; font-size: 0.95rem; text-align: center; word-break: break-word; }
.peer-status { font-size: 0.75rem; color: var(--text-muted); text-transform: uppercase; letter-spacing: 0.05em; }

.peer-actions { display: flex; gap: 8px; width: 100%; }
.peer-actions button { flex: 1; }

/* File input inside peer card */
.peer-file-input { display: none; }

/* Peer card sections */
.peer-section { width: 100%; display: flex; flex-direction: column; gap: 8px; }
.peer-section-label {
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  border-bottom: 1px solid var(--border);
  padding-bottom: 4px;
}

.peer-messages {
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 6px;
  max-height: 160px;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
}

.msg-bubble {
  background: var(--bg);
  border-radius: 10px 10px 10px 2px;
  padding: 8px 12px;
  font-size: 0.82rem;
  line-height: 1.4;
  word-break: break-word;
  align-self: flex-start;
  max-width: 90%;
  min-height: 36px;
  display: flex;
  align-items: center;
  cursor: pointer;
  user-select: none;
  -webkit-user-select: none;
  touch-action: manipulation;
  transition: opacity 0.15s, background 0.1s;
}
.msg-bubble:hover { opacity: 0.75; }
.msg-bubble:active { opacity: 0.5; }
.msg-bubble.own {
  background: var(--accent);
  color: #fff;
  border-radius: 10px 10px 2px 10px;
  align-self: flex-end;
}

.peer-msg-input-row { display: flex; gap: 6px; }
.peer-msg-input {
  flex: 1;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text);
  font-size: 0.8rem;
  padding: 6px 10px;
  resize: none;
  min-height: 0;
  transition: var(--transition);
}
.peer-msg-input:focus { outline: none; border-color: var(--accent); }
.peer-msg-send {
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 8px;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: var(--transition);
}
.peer-msg-send:hover { background: var(--accent-hover); }

.peer-transfer-area {
  width: 100%;
  min-height: 60px;
  border: 1px dashed var(--border);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.78rem;
  color: var(--text-muted);
  transition: var(--transition);
  cursor: pointer;
  padding: 8px;
  text-align: center;
}
.peer-transfer-area:hover { border-color: var(--accent); color: var(--accent); background: var(--accent-glow); }
.peer-transfer-area.drag-over { border-color: var(--accent); background: var(--accent-glow); color: var(--text); }

/* ── Transfer Queue ──────────────────────────────────────────────── */
.transfer-queue {
  position: fixed;
  bottom: 20px;
  right: 20px;
  display: flex;
  flex-direction: column-reverse;
  gap: 10px;
  z-index: 150;
  max-width: 360px;
  width: 100%;
  pointer-events: none;
}
.transfer-queue:empty { display: none; }

.transfer-item {
  background: var(--bg2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  box-shadow: var(--shadow);
  pointer-events: all;
  animation: slideIn 0.25s ease;
}
@keyframes slideIn { from { opacity:0; transform:translateY(20px); } to { opacity:1; transform:none; } }

.transfer-header { display: flex; align-items: center; gap: 10px; }
.transfer-icon { color: var(--accent); flex-shrink: 0; }
.transfer-info  { flex: 1; min-width: 0; }
.transfer-name { font-weight: 600; font-size: 0.88rem; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.transfer-meta  { font-size: 0.75rem; color: var(--text-muted); }
.transfer-close {
  background: transparent;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 4px;
  border-radius: 4px;
  transition: var(--transition);
  flex-shrink: 0;
}
.transfer-close:hover { color: var(--error); background: rgba(231,76,60,0.1); }

.progress-bar {
  height: 4px;
  background: var(--bg);
  border-radius: 2px;
  overflow: hidden;
}
.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent), #7b8fff);
  border-radius: 2px;
  transition: width 0.15s ease;
}
.progress-fill.done { background: var(--success); }

/* ── Toast ────────────────────────────────────────────────────────── */
.toast {
  position: fixed;
  bottom: 100px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--surface);
  color: var(--text);
  padding: 12px 24px;
  border-radius: var(--radius);
  font-size: 0.88rem;
  font-weight: 600;
  box-shadow: var(--shadow);
  z-index: 300;
  pointer-events: none;
  transition: opacity 0.3s ease, transform 0.3s ease;
  white-space: nowrap;
}
.toast.hidden { opacity: 0; transform: translateX(-50%) translateY(10px); pointer-events: none; }
.toast.success { border-left: 3px solid var(--success); }
.toast.error   { border-left: 3px solid var(--error); }
.toast.info    { border-left: 3px solid var(--accent); }

/* ── Utility ─────────────────────────────────────────────────────── */
.hidden { display: none !important; }

/* ── Responsive ──────────────────────────────────────────────────── */
@media (max-width: 600px) {
  header { padding: 12px 16px; }
  .logo span { display: none; }
  .join-card { margin-top: 24px; padding: 24px 20px; }
  .transfer-queue { bottom: 12px; right: 12px; left: 12px; max-width: none; }
}