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

/* ── Design tokens ──────────────────────────────────────────────────────────── */
:root {
  /* backgrounds */
  --bg-0: #05080d;
  --bg-1: #090d15;
  --bg-2: #0d1320;
  --bg-3: #121a28;

  /* borders */
  --b-dim:  #18222f;
  --b-mid:  #1f2d3d;
  --b-gold: rgba(200, 168, 110, 0.30);

  /* text */
  --t-0: #ede0cc;
  --t-1: #9a8f7c;
  --t-2: #52473a;

  /* accent — pale Hellenic gold */
  --gold:      #c8a86e;
  --gold-l:    #e4c48a;
  --gold-glow: rgba(200, 168, 110, 0.55);
  --gold-dim:  rgba(200, 168, 110, 0.10);
  --gold-dim2: rgba(200, 168, 110, 0.05);

  /* layout */
  --sidebar-w: 264px;
  --r: 4px;

  /* typography */
  --font-serif: 'Cinzel', serif;
  --font-mono:  'IBM Plex Mono', monospace;

  /* motion */
  --ease: cubic-bezier(0.4, 0, 0.2, 1);
  --t-fast: 160ms;
  --t-mid:  240ms;
}

/* ── Base ───────────────────────────────────────────────────────────────────── */
html, body { height: 100%; overflow: hidden; }

body {
  font-family: var(--font-mono);
  font-size: 13.5px;
  line-height: 1.72;
  color: var(--t-0);
  background: var(--bg-0);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ── Grain overlay ──────────────────────────────────────────────────────────── */
/*
 * SVG fractalNoise filter rendered into a repeating tile.
 * Creates subtle analogue texture without any image assets.
 */
.noise-overlay {
  position: fixed;
  inset: 0;
  z-index: 9999;
  pointer-events: none;
  opacity: 0.028;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='300' height='300'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='300' height='300' filter='url(%23n)'/%3E%3C/svg%3E");
  background-repeat: repeat;
  background-size: 300px 300px;
}

/* ── App shell ──────────────────────────────────────────────────────────────── */
.app {
  display: flex;
  height: 100vh;
  overflow: hidden;
}

/* ════════════════════════════════════════════════════════════════════════════
   SIDEBAR
   ════════════════════════════════════════════════════════════════════════════ */
.sidebar {
  width: var(--sidebar-w);
  min-width: var(--sidebar-w);
  background: var(--bg-1);
  border-right: 1px solid var(--b-dim);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  position: relative;

  animation: slideInLeft 0.45s var(--ease) both;
}

/* thin gold shimmer on the far-left edge */
.sidebar::after {
  content: '';
  position: absolute;
  left: 0; top: 0; bottom: 0;
  width: 1px;
  background: linear-gradient(
    to bottom,
    transparent 0%,
    var(--gold) 40%,
    var(--gold) 60%,
    transparent 100%
  );
  opacity: 0.18;
  pointer-events: none;
}

/* ── Sidebar top block ──────────────────────────────────────────────────────── */
.sidebar-top {
  padding: 24px 16px 20px;
  border-bottom: 1px solid var(--b-dim);
  flex-shrink: 0;
}

/* ── Logo ───────────────────────────────────────────────────────────────────── */
.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 20px;
  user-select: none;
}

.logo-mark {
  font-family: var(--font-serif);
  font-size: 30px;
  color: var(--gold);
  line-height: 1;
  filter: drop-shadow(0 0 7px var(--gold-glow));
  transition: filter var(--t-mid) var(--ease);
}

/* Ψ pulses while the AI is generating */
.logo-mark.thinking {
  animation: psiPulse 1.4s ease-in-out infinite;
}

.logo-info { display: flex; flex-direction: column; gap: 1px; }

.logo-name {
  font-family: var(--font-serif);
  font-size: 15px;
  letter-spacing: 0.14em;
  color: var(--t-0);
  line-height: 1;
}

.logo-tagline {
  font-size: 8.5px;
  letter-spacing: 0.26em;
  text-transform: uppercase;
  color: var(--t-2);
}

/* ── New chat button ────────────────────────────────────────────────────────── */
.btn-new {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 9px 14px;
  background: transparent;
  border: 1px solid var(--b-mid);
  border-radius: var(--r);
  color: var(--t-1);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.06em;
  cursor: pointer;
  position: relative;
  overflow: hidden;
  transition: color var(--t-fast) var(--ease),
              border-color var(--t-fast) var(--ease);
}

/* hover fill via pseudo — avoids layout repaint */
.btn-new::before {
  content: '';
  position: absolute;
  inset: 0;
  background: var(--gold-dim);
  opacity: 0;
  transition: opacity var(--t-fast) var(--ease);
}

.btn-new:hover { color: var(--gold-l); border-color: var(--b-gold); }
.btn-new:hover::before { opacity: 1; }

.btn-new-icon { color: var(--gold); flex-shrink: 0; }

/* ── Section label ──────────────────────────────────────────────────────────── */
.sidebar-label {
  padding: 14px 16px 5px;
  font-size: 8.5px;
  letter-spacing: 0.28em;
  color: var(--t-2);
  text-transform: uppercase;
  flex-shrink: 0;
  user-select: none;
}

/* ── Chat list ──────────────────────────────────────────────────────────────── */
.chat-list {
  flex: 1;
  overflow-y: auto;
  padding: 4px 8px 8px;
}

.chat-list::-webkit-scrollbar { width: 3px; }
.chat-list::-webkit-scrollbar-thumb { background: var(--b-mid); border-radius: 2px; }
.chat-list::-webkit-scrollbar-track { background: transparent; }

.no-chats {
  padding: 14px 8px;
  font-size: 11px;
  font-style: italic;
  color: var(--t-2);
}

/* ── Chat item ──────────────────────────────────────────────────────────────── */
.chat-item {
  padding: 9px 8px 9px 14px;
  border-radius: var(--r);
  border: 1px solid transparent;
  margin-bottom: 2px;
  cursor: pointer;
  position: relative;
  overflow: hidden;
  display: flex;
  align-items: center;
  gap: 6px;
  transition: background var(--t-fast) var(--ease),
              border-color var(--t-fast) var(--ease);
}

/* animated accent bar on the left */
.chat-item::before {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 2px;
  height: 0;
  background: var(--gold);
  border-radius: 1px;
  transition: height var(--t-mid) var(--ease);
}

.chat-item:hover::before,
.chat-item.active::before { height: 55%; }

.chat-item:hover {
  background: var(--bg-3);
  border-color: var(--b-dim);
}

.chat-item.active {
  background: var(--gold-dim);
  border-color: var(--b-gold);
}

.chat-item-body {
  flex: 1;
  min-width: 0; /* consente il text-overflow sui figli */
}

.chat-item-title {
  font-size: 11.5px;
  color: var(--t-0);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  margin-bottom: 2px;
  transition: color var(--t-fast) var(--ease);
}

.chat-item.active .chat-item-title { color: var(--gold-l); }

.chat-item-preview {
  font-size: 10.5px;
  color: var(--t-2);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* ── Delete button (visibile solo all'hover sul chat-item) ───────────────────── */
.chat-delete-btn {
  flex-shrink: 0;
  width: 24px;
  height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: transparent;
  border: 1px solid transparent;
  border-radius: var(--r);
  color: var(--t-2);
  cursor: pointer;
  opacity: 0;
  transition: opacity var(--t-fast) var(--ease),
              color var(--t-fast) var(--ease),
              border-color var(--t-fast) var(--ease),
              background var(--t-fast) var(--ease);
}

.chat-item:hover .chat-delete-btn { opacity: 1; }

.chat-delete-btn:hover {
  color: #e06060;
  border-color: rgba(224, 96, 96, 0.3);
  background: rgba(224, 96, 96, 0.08);
}

/* ── Sidebar footer ─────────────────────────────────────────────────────────── */
.sidebar-footer {
  padding: 12px 16px;
  border-top: 1px solid var(--b-dim);
  font-size: 9.5px;
  letter-spacing: 0.04em;
  color: var(--t-2);
  flex-shrink: 0;
}

/* ════════════════════════════════════════════════════════════════════════════
   MAIN AREA
   ════════════════════════════════════════════════════════════════════════════ */
.main {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  background: var(--bg-0);
  position: relative;
  animation: fadeIn 0.5s 0.1s var(--ease) both;
}

/* ── Empty state ────────────────────────────────────────────────────────────── */
.empty-state {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 14px;
  padding: 40px;
  text-align: center;
  animation: fadeIn 0.6s 0.2s var(--ease) both;
}

.empty-psi {
  font-family: var(--font-serif);
  font-size: 80px;
  line-height: 1;
  color: var(--gold);
  opacity: 0.12;
  filter: drop-shadow(0 0 30px var(--gold-glow));
  animation: floatPsi 5s ease-in-out infinite;
  user-select: none;
}

.empty-title {
  font-family: var(--font-serif);
  font-size: 19px;
  font-weight: 400;
  letter-spacing: 0.05em;
  color: var(--t-1);
}

.empty-sub {
  font-size: 11.5px;
  color: var(--t-2);
  max-width: 260px;
  line-height: 1.6;
}

/* ── Chat wrap (message scroll container) ───────────────────────────────────── */
.chat-wrap {
  flex: 1;
  overflow-y: auto;
  padding: 36px 0 24px;
  display: none;
}

.chat-wrap.visible { display: block; }

.chat-wrap::-webkit-scrollbar { width: 4px; }
.chat-wrap::-webkit-scrollbar-thumb { background: var(--b-mid); border-radius: 2px; }
.chat-wrap::-webkit-scrollbar-track { background: transparent; }

/* ── Messages list ──────────────────────────────────────────────────────────── */
.messages {
  max-width: 700px;
  margin: 0 auto;
  padding: 0 28px;
  display: flex;
  flex-direction: column;
  gap: 32px;
}

/* ── Single message ─────────────────────────────────────────────────────────── */
.msg {
  display: flex;
  flex-direction: column;
  gap: 7px;
  animation: msgIn 0.32s var(--ease) both;
}

.msg-header {
  display: flex;
  align-items: center;
  gap: 9px;
}

/* avatar dot */
.msg-avatar {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 10px;
  flex-shrink: 0;
  line-height: 1;
}

.msg.user .msg-avatar {
  background: var(--bg-3);
  border: 1px solid var(--b-mid);
  color: var(--t-1);
}

.msg.assistant .msg-avatar {
  background: var(--gold-dim);
  border: 1px solid var(--b-gold);
  color: var(--gold);
  font-family: var(--font-serif);
  font-size: 11px;
}

.msg-role {
  font-size: 9.5px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--t-2);
}

/* message body */
.msg-body {
  padding-left: 31px;
  font-size: 13.5px;
  line-height: 1.78;
  color: var(--t-0);
  white-space: pre-wrap;
  word-break: break-word;
}

.msg.user .msg-body { color: var(--t-1); }

/*
 * Blinking block cursor shown while the AI response is still streaming.
 * Removed via JS once the stream ends.
 */
.msg-body.streaming::after {
  content: '▋';
  color: var(--gold);
  animation: blink 0.75s step-end infinite;
  margin-left: 1px;
}

/* ── Welcome card (chat appena creata, nessun messaggio) ────────────────────── */
.welcome {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: 48px 24px 32px;
  gap: 12px;
  animation: msgIn 0.4s var(--ease) both;
}

.welcome-symbol {
  font-family: var(--font-serif);
  font-size: 52px;
  line-height: 1;
  color: var(--gold);
  filter: drop-shadow(0 0 14px var(--gold-glow));
  margin-bottom: 4px;
  user-select: none;
}

.welcome-name {
  font-family: var(--font-serif);
  font-size: 20px;
  font-weight: 600;
  letter-spacing: 0.18em;
  color: var(--t-0);
}

.welcome-desc {
  font-size: 12.5px;
  color: var(--t-1);
  line-height: 1.8;
  max-width: 380px;
}

.welcome-desc strong { color: var(--gold-l); font-weight: 500; }

.welcome-credits {
  font-size: 11px;
  color: var(--t-2);
  line-height: 1.7;
  font-style: italic;
  border-top: 1px solid var(--b-dim);
  padding-top: 12px;
  margin-top: 4px;
}

.welcome-credits strong { color: var(--t-1); font-weight: 500; font-style: normal; }

.welcome-hints {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: center;
  margin-top: 8px;
}

.hint {
  padding: 5px 12px;
  border: 1px solid var(--b-mid);
  border-radius: var(--r);
  font-size: 11px;
  color: var(--t-2);
  background: var(--bg-2);
  letter-spacing: 0.02em;
}

/* ════════════════════════════════════════════════════════════════════════════
   INPUT AREA
   ════════════════════════════════════════════════════════════════════════════ */
.input-area {
  padding: 14px 24px 18px;
  border-top: 1px solid var(--b-dim);
  flex-shrink: 0;
  background: var(--bg-0);
  display: none;
}

.input-area.visible { display: block; }

.input-box {
  max-width: 700px;
  margin: 0 auto;
  display: flex;
  align-items: flex-end;
  gap: 10px;
  background: var(--bg-2);
  border: 1px solid var(--b-mid);
  border-radius: var(--r);
  padding: 10px 12px;
  transition: border-color var(--t-fast) var(--ease);
}

.input-box:focus-within { border-color: var(--b-gold); }

.msg-input {
  flex: 1;
  background: transparent;
  border: none;
  outline: none;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--t-0);
  resize: none;
  max-height: 160px;
  line-height: 1.65;
  caret-color: var(--gold);
}

.msg-input::placeholder { color: var(--t-2); }

.send-btn {
  width: 32px;
  height: 32px;
  border-radius: var(--r);
  border: 1px solid var(--b-mid);
  background: transparent;
  color: var(--t-2);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: color var(--t-fast) var(--ease),
              border-color var(--t-fast) var(--ease),
              background var(--t-fast) var(--ease);
}

.send-btn:not(:disabled):hover {
  color: var(--gold-l);
  border-color: var(--b-gold);
  background: var(--gold-dim);
}

.send-btn:disabled { opacity: 0.35; cursor: not-allowed; }

.input-note {
  max-width: 700px;
  margin: 8px auto 0;
  font-size: 9.5px;
  color: var(--t-2);
  text-align: center;
  letter-spacing: 0.03em;
}

/* ════════════════════════════════════════════════════════════════════════════
   KEYFRAME ANIMATIONS
   ════════════════════════════════════════════════════════════════════════════ */

@keyframes slideInLeft {
  from { transform: translateX(-16px); opacity: 0; }
  to   { transform: translateX(0);     opacity: 1; }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to   { opacity: 1; }
}

@keyframes msgIn {
  from { transform: translateY(8px); opacity: 0; }
  to   { transform: translateY(0);   opacity: 1; }
}

/* Logo Ψ glows rhythmically while the AI is thinking */
@keyframes psiPulse {
  0%, 100% { filter: drop-shadow(0 0 7px var(--gold-glow)); }
  50%       { filter: drop-shadow(0 0 22px var(--gold-glow))
                       drop-shadow(0 0 40px rgba(200, 168, 110, 0.3)); }
}

/* Large empty-state Ψ floats gently */
@keyframes floatPsi {
  0%, 100% { transform: translateY(0px); }
  50%       { transform: translateY(-12px); }
}

@keyframes blink {
  0%, 100% { opacity: 1; }
  50%       { opacity: 0; }
}

/* ── Mobile bar (nascosta su desktop) ───────────────────────────────────────── */
.mobile-bar { display: none; }

/* ════════════════════════════════════════════════════════════════════════════
   RESPONSIVE — tablet stretto
   ════════════════════════════════════════════════════════════════════════════ */
@media (max-width: 720px) {
  :root { --sidebar-w: 220px; }
  .logo-tagline { display: none; }
  .messages { padding: 0 16px; }
}

/* ════════════════════════════════════════════════════════════════════════════
   RESPONSIVE — mobile (pannelli scorrevoli)
   Pattern: sidebar e main occupano tutta la schermata.
   Di default la sidebar è visibile. Aggiungendo .chat-open al .app,
   la sidebar scorre a sinistra e il main entra da destra.
   ════════════════════════════════════════════════════════════════════════════ */
@media (max-width: 600px) {

  /* L'app diventa un contenitore a schermo intero senza overflow */
  .app {
    position: relative;
    overflow: hidden;
  }

  /* Sidebar: pannello sinistro, occupa tutto lo schermo */
  .sidebar {
    position: absolute;
    inset: 0;
    width: 100%;
    min-width: 100%;
    z-index: 20;
    transform: translateX(0);
    transition: transform var(--t-mid) var(--ease);
    animation: none;
  }

  /* Quando la chat è aperta, la sidebar scorre fuori a sinistra */
  .app.chat-open .sidebar {
    transform: translateX(-100%);
    pointer-events: none;
  }

  /* Main: pannello destro, inizialmente fuori schermo a destra */
  .main {
    position: absolute;
    inset: 0;
    transform: translateX(100%);
    transition: transform var(--t-mid) var(--ease);
    animation: none;
  }

  /* Quando la chat è aperta, il main scorre dentro */
  .app.chat-open .main {
    transform: translateX(0);
  }

  /* Barra mobile: back + titolo chat + logo Ψ */
  .mobile-bar {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 12px 14px;
    border-bottom: 1px solid var(--b-dim);
    flex-shrink: 0;
    background: var(--bg-1);
  }

  .btn-back {
    width: 34px;
    height: 34px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: transparent;
    border: 1px solid var(--b-mid);
    border-radius: var(--r);
    color: var(--t-1);
    cursor: pointer;
    flex-shrink: 0;
    transition: color var(--t-fast) var(--ease),
                border-color var(--t-fast) var(--ease);
  }

  .btn-back:hover { color: var(--gold); border-color: var(--b-gold); }

  .mobile-chat-title {
    flex: 1;
    font-family: var(--font-mono);
    font-size: 12px;
    letter-spacing: 0.08em;
    color: var(--t-1);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }

  .mobile-logo-mark {
    font-family: var(--font-serif);
    font-size: 22px;
    color: var(--gold);
    filter: drop-shadow(0 0 6px var(--gold-glow));
    flex-shrink: 0;
  }

  .mobile-logo-mark.thinking {
    animation: psiPulse 1.4s ease-in-out infinite;
  }

  /* Su mobile il bottone elimina è sempre visibile (niente hover su touch) */
  .chat-delete-btn { opacity: 1; }

  /* Padding inferiore per safe area iOS */
  .input-area {
    padding-bottom: calc(14px + env(safe-area-inset-bottom, 0px));
  }

  /* Dimensioni touch-friendly per l'input */
  .msg-input { font-size: 16px; } /* evita lo zoom automatico su iOS */

  /* Sidebar: font e padding leggermente più grandi */
  .chat-item { padding: 12px 8px 12px 14px; }
  .chat-item-title { font-size: 13px; }
  .chat-item-preview { font-size: 11.5px; }

  /* Welcome card: meno padding verticale */
  .welcome { padding: 28px 16px 20px; }
  .welcome-symbol { font-size: 40px; }
  .welcome-hints { display: none; } /* troppo strette su mobile */
}