@import url('https://fonts.googleapis.com/css2?family=Lexend:wght@400;500;600;700&family=Source+Sans+3:wght@400;500;600&display=swap');

/* --- Design system: Trust & Authority (generated via ui-ux-pro-max) --- */

:root {
  /* Semantic color tokens (light) */
  --color-primary: #0F766E;
  --color-primary-hover: #0E6A63;
  --color-on-primary: #FFFFFF;
  --color-secondary: #14B8A6;
  --color-accent: #0369A1;
  --color-accent-hover: #075985;
  --color-background: #F0FDFA;
  --color-surface: #FFFFFF;
  --color-surface-2: #F8FAFA;
  --color-foreground: #134E4A;
  --color-foreground-muted: #4B6663;
  --color-muted: #E8F0F3;
  --color-border: #CDE8E4;
  --color-border-strong: #99F6E4;
  --color-destructive: #DC2626;
  --color-destructive-on: #FFFFFF;
  --color-success: #047857;
  --color-warning: #B45309;
  --color-ring: #0F766E;

  /* Type scale */
  --font-heading: 'Lexend', system-ui, sans-serif;
  --font-body: 'Source Sans 3', system-ui, sans-serif;
  --fs-xs: 12px;
  --fs-sm: 14px;
  --fs-base: 16px;
  --fs-lg: 18px;
  --fs-xl: 22px;
  --fs-2xl: 28px;
  --fs-3xl: 36px;

  /* Spacing (4/8 rhythm) */
  --sp-1: 4px; --sp-2: 8px; --sp-3: 12px; --sp-4: 16px;
  --sp-5: 20px; --sp-6: 24px; --sp-8: 32px; --sp-10: 40px; --sp-12: 48px;

  /* Radii & elevation */
  --radius-sm: 6px;
  --radius: 10px;
  --radius-lg: 14px;
  --elev-1: 0 1px 2px rgba(15, 118, 110, 0.06), 0 1px 3px rgba(15, 118, 110, 0.08);
  --elev-2: 0 4px 12px rgba(15, 118, 110, 0.08), 0 2px 4px rgba(15, 118, 110, 0.06);
  --elev-3: 0 12px 32px rgba(15, 118, 110, 0.10), 0 4px 8px rgba(15, 118, 110, 0.06);

  /* Motion */
  --dur-fast: 150ms;
  --dur-med: 220ms;
  --easing: cubic-bezier(0.2, 0.8, 0.2, 1);
}

@media (prefers-color-scheme: dark) {
  :root {
    --color-primary: #14B8A6;
    --color-primary-hover: #2DD4BF;
    --color-on-primary: #062E2A;
    --color-secondary: #2DD4BF;
    --color-accent: #38BDF8;
    --color-accent-hover: #7DD3FC;
    --color-background: #0B1F1D;
    --color-surface: #102E2B;
    --color-surface-2: #143A36;
    --color-foreground: #E6FFFB;
    --color-foreground-muted: #9DBDB9;
    --color-muted: #143A36;
    --color-border: #1F4A45;
    --color-border-strong: #2C6962;
    --color-destructive: #F87171;
    --color-success: #34D399;
    --color-warning: #FBBF24;
    --color-ring: #2DD4BF;
    --elev-1: 0 1px 2px rgba(0, 0, 0, 0.4);
    --elev-2: 0 4px 12px rgba(0, 0, 0, 0.45);
    --elev-3: 0 12px 32px rgba(0, 0, 0, 0.55);
  }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}

/* --- Base --- */
* { box-sizing: border-box; }

html { color-scheme: light dark; }

body {
  margin: 0;
  font-family: var(--font-body);
  font-size: var(--fs-base);
  line-height: 1.6;
  background: var(--color-background);
  color: var(--color-foreground);
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  font-family: var(--font-heading);
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--color-foreground);
  margin: 0 0 var(--sp-3);
}
h1 { font-size: var(--fs-3xl); line-height: 1.2; }
h2 { font-size: var(--fs-2xl); line-height: 1.25; }
h3 { font-size: var(--fs-xl); line-height: 1.3; }

a { color: var(--color-accent); text-decoration: none; transition: color var(--dur-fast) var(--easing); }
a:hover { color: var(--color-accent-hover); text-decoration: underline; }

:focus-visible {
  outline: 2px solid var(--color-ring);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* --- Header --- */
header.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-4);
  padding: var(--sp-4) var(--sp-6);
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 10;
}
header.app-header h1 {
  margin: 0;
  font-size: var(--fs-lg);
  font-weight: 600;
}
header.app-header .brand { color: var(--color-foreground); text-decoration: none; display: inline-flex; align-items: center; gap: var(--sp-2); }
header.app-header .brand:hover { text-decoration: none; }
header.app-header .actions { display: flex; gap: var(--sp-3); align-items: center; }

/* --- Layout --- */
.container {
  max-width: 960px;
  margin: 0 auto;
  padding: var(--sp-8) var(--sp-6);
}
.container.narrow { max-width: 460px; }

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--sp-6);
  box-shadow: var(--elev-1);
}
.card + .card { margin-top: var(--sp-4); }

.row { display: flex; gap: var(--sp-3); align-items: center; flex-wrap: wrap; }
.row.between { justify-content: space-between; }

/* --- Forms --- */
.field { margin-bottom: var(--sp-4); }
label {
  display: block;
  margin-bottom: var(--sp-2);
  font-size: var(--fs-sm);
  font-weight: 500;
  color: var(--color-foreground);
}
label .req { color: var(--color-destructive); margin-left: 2px; }

input[type="text"], input[type="password"], input[type="date"],
input[type="number"], input[type="url"], input[type="email"], textarea {
  width: 100%;
  padding: 10px 12px;
  min-height: 44px;
  background: var(--color-surface);
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius);
  color: var(--color-foreground);
  font-size: var(--fs-base);
  font-family: inherit;
  transition: border-color var(--dur-fast) var(--easing), box-shadow var(--dur-fast) var(--easing);
}
input::placeholder, textarea::placeholder { color: var(--color-foreground-muted); }

input:hover, textarea:hover { border-color: var(--color-primary); }
input:focus-visible, textarea:focus-visible {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(15, 118, 110, 0.18);
}

textarea { resize: vertical; min-height: 88px; }

.helper { font-size: var(--fs-sm); color: var(--color-foreground-muted); margin-top: var(--sp-1); }

/* --- Buttons --- */
button, .btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--sp-2);
  padding: 10px 18px;
  min-height: 44px;
  background: var(--color-primary);
  color: var(--color-on-primary);
  border: 1px solid var(--color-primary);
  border-radius: var(--radius);
  font-weight: 600;
  font-size: var(--fs-sm);
  font-family: inherit;
  cursor: pointer;
  text-decoration: none;
  transition: background var(--dur-fast) var(--easing),
              border-color var(--dur-fast) var(--easing),
              transform var(--dur-fast) var(--easing),
              box-shadow var(--dur-fast) var(--easing);
}
button:hover, .btn:hover {
  background: var(--color-primary-hover);
  border-color: var(--color-primary-hover);
  text-decoration: none;
  color: var(--color-on-primary);
}
button:active, .btn:active { transform: scale(0.98); }
button:disabled, .btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}

.btn-secondary {
  background: var(--color-surface);
  color: var(--color-foreground);
  border-color: var(--color-border-strong);
}
.btn-secondary:hover {
  background: var(--color-muted);
  color: var(--color-foreground);
  border-color: var(--color-primary);
}

.btn-accent { background: var(--color-accent); border-color: var(--color-accent); }
.btn-accent:hover { background: var(--color-accent-hover); border-color: var(--color-accent-hover); }

.btn-danger { background: var(--color-destructive); border-color: var(--color-destructive); color: var(--color-destructive-on); }
.btn-danger:hover { background: #B91C1C; border-color: #B91C1C; color: var(--color-destructive-on); }

.btn-ghost {
  background: transparent;
  color: var(--color-foreground);
  border-color: transparent;
}
.btn-ghost:hover { background: var(--color-muted); color: var(--color-foreground); }

/* --- Status feedback --- */
.error[role="alert"], .error { color: var(--color-destructive); font-size: var(--fs-sm); margin-top: var(--sp-2); min-height: 20px; }
.success { color: var(--color-success); font-size: var(--fs-sm); margin-top: var(--sp-2); min-height: 20px; }
.muted { color: var(--color-foreground-muted); font-size: var(--fs-sm); }
.small { font-size: var(--fs-xs); }

/* --- Badges --- */
.badge {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-1);
  padding: 2px 10px;
  border-radius: 999px;
  font-size: var(--fs-xs);
  font-weight: 600;
  font-family: var(--font-heading);
  letter-spacing: 0.02em;
  text-transform: uppercase;
  transition: transform var(--dur-fast) var(--easing);
}
.badge.active { background: rgba(4, 120, 87, 0.12); color: var(--color-success); }
.badge.warning { background: rgba(180, 83, 9, 0.12); color: var(--color-warning); }
.badge.dissolved { background: rgba(220, 38, 38, 0.12); color: var(--color-destructive); }
.badge:hover { transform: translateY(-1px); }

.code {
  font-family: ui-monospace, 'SF Mono', Consolas, monospace;
  background: var(--color-muted);
  color: var(--color-foreground);
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  font-size: var(--fs-base);
  letter-spacing: 2px;
  font-weight: 600;
}

/* --- Room list --- */
.room-list { display: grid; gap: var(--sp-3); }
.room-card {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--sp-3);
  padding: var(--sp-4);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  transition: border-color var(--dur-fast) var(--easing), box-shadow var(--dur-fast) var(--easing);
}
.room-card:hover { border-color: var(--color-primary); box-shadow: var(--elev-2); }
.room-card a { color: var(--color-foreground); text-decoration: none; flex: 1; display: block; }
.room-card a:hover { text-decoration: none; }
.room-card a:hover h3 { color: var(--color-primary); }
.room-card h3 { margin: 0 0 var(--sp-1) 0; font-size: var(--fs-lg); transition: color var(--dur-fast) var(--easing); }
.room-card .meta { font-size: var(--fs-sm); color: var(--color-foreground-muted); }

/* --- Messages --- */
.messages {
  max-height: 60vh;
  overflow-y: auto;
  padding: var(--sp-4);
  background: var(--color-surface-2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  display: flex;
  flex-direction: column;
  gap: var(--sp-3);
}
.message {
  padding: var(--sp-3) var(--sp-4);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  max-width: 80%;
  box-shadow: var(--elev-1);
}
.message.trainer { align-self: flex-start; border-left: 3px solid var(--color-primary); }
.message.participant { align-self: flex-end; background: var(--color-muted); }
.message .meta {
  font-size: var(--fs-xs);
  color: var(--color-foreground-muted);
  margin-bottom: var(--sp-1);
  display: flex; gap: var(--sp-2);
}
.message .meta .name { font-weight: 600; color: var(--color-foreground); }
.message a { word-break: break-all; }

.message .file-attach {
  display: flex; align-items: center; gap: var(--sp-3);
  padding: var(--sp-3); background: var(--color-surface-2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  margin-top: var(--sp-2);
}
.message .file-attach .name { font-size: var(--fs-sm); word-break: break-all; flex: 1; display: inline-flex; align-items: center; gap: var(--sp-2); }
.message .file-attach .icon { color: var(--color-primary); flex-shrink: 0; }

.composer { display: flex; flex-direction: column; gap: var(--sp-3); margin-top: var(--sp-4); }

/* --- Drop zone --- */
.drop-zone {
  display: block;
  border: 2px dashed var(--color-border-strong);
  border-radius: var(--radius-lg);
  padding: var(--sp-6);
  text-align: center;
  color: var(--color-foreground-muted);
  cursor: pointer;
  background: var(--color-surface-2);
  transition: border-color var(--dur-fast) var(--easing),
              background var(--dur-fast) var(--easing),
              color var(--dur-fast) var(--easing);
}
.drop-zone:hover, .drop-zone.dragging {
  border-color: var(--color-primary);
  background: rgba(15, 118, 110, 0.05);
  color: var(--color-foreground);
}
.drop-zone input[type="file"] { display: none; }
.drop-zone .icon { color: var(--color-primary); margin-bottom: var(--sp-2); }

/* --- Tabs --- */
.tabs {
  display: flex;
  gap: var(--sp-1);
  margin-bottom: var(--sp-4);
  border-bottom: 1px solid var(--color-border);
}
.tabs button {
  background: transparent;
  color: var(--color-foreground-muted);
  padding: var(--sp-2) var(--sp-4);
  border: none;
  border-radius: 0;
  border-bottom: 2px solid transparent;
  font-weight: 500;
  font-size: var(--fs-sm);
  min-height: 40px;
  transition: color var(--dur-fast) var(--easing),
              border-color var(--dur-fast) var(--easing);
}
.tabs button:hover { color: var(--color-foreground); background: transparent; border-bottom-color: transparent; }
.tabs button.active { color: var(--color-primary); border-bottom-color: var(--color-primary); }

/* --- QR --- */
.qr-wrap { background: white; padding: var(--sp-4); border-radius: var(--radius); display: inline-block; box-shadow: var(--elev-2); }
.qr-wrap svg { display: block; }

/* --- Hero (landing) --- */
.hero { text-align: center; padding: var(--sp-12) var(--sp-6) var(--sp-8); }
.hero h1 { font-size: var(--fs-3xl); margin-bottom: var(--sp-3); }
.hero p { color: var(--color-foreground-muted); font-size: var(--fs-lg); max-width: 560px; margin: 0 auto var(--sp-6); }
.hero .row { justify-content: center; }

.trust-strip {
  display: flex;
  gap: var(--sp-6);
  justify-content: center;
  flex-wrap: wrap;
  margin-top: var(--sp-6);
  padding: var(--sp-4);
  color: var(--color-foreground-muted);
  font-size: var(--fs-sm);
}
.trust-strip .item { display: inline-flex; align-items: center; gap: var(--sp-2); }
.trust-strip .item svg { color: var(--color-primary); }

/* --- Inline SVG icon defaults --- */
.icon { display: inline-block; vertical-align: middle; flex-shrink: 0; }

/* --- Responsive --- */
@media (max-width: 640px) {
  .container { padding: var(--sp-5) var(--sp-4); }
  h1 { font-size: var(--fs-2xl); }
  .message { max-width: 92%; }
  header.app-header { padding: var(--sp-3) var(--sp-4); }
  .hero { padding: var(--sp-8) var(--sp-4); }
}