:root {
  --bg-void:     #05060A;
  --bg-base:     #0B0D14;
  --bg-surface:  #111420;
  --bg-elevated: #181C2C;
  --bg-input:    #171A26;

  --accent:      #3DD68C;
  --accent-h:    #52E09E;
  --accent-g1:   rgba(61,214,140,.10);
  --accent-g2:   rgba(61,214,140,.22);

  --ok:   #3DD68C;
  --err:  #F06579;

  --tx-1: #EDF0F7;
  --tx-2: #8892A4;
  --tx-3: #4A5468;

  --bd:   rgba(255,255,255,.08);
  --bd-m: rgba(255,255,255,.14);

  --sh-md: 0 8px 32px rgba(0,0,0,.40);
  --sidebar-w: 250px;
  --r-s: 8px; --r-m: 12px; --r-l: 16px; --r-f: 9999px;
  --t: .18s cubic-bezier(.4,0,.2,1);
}

[data-theme="light"] {
  --bg-void:     #F0F3FA;
  --bg-base:     #FFFFFF;
  --bg-surface:  #F4F6FC;
  --bg-elevated: #E8ECF7;
  --bg-input:    #F4F6FC;
  --accent:      #1E9E64;
  --accent-h:    #17824F;
  --accent-g1:   rgba(30,158,100,.08);
  --accent-g2:   rgba(30,158,100,.16);
  --ok:  #1E9E64;
  --err: #D0384A;
  --tx-1: #0D1117;
  --tx-2: #4B5566;
  --tx-3: #94A3B8;
  --bd:   rgba(0,0,0,.08);
  --bd-m: rgba(0,0,0,.14);
  --sh-md: 0 8px 32px rgba(0,0,0,.10);
}

* { box-sizing: border-box; }
html, body { margin: 0; height: 100%; background: var(--bg-void); color: var(--tx-1);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; }
.hidden { display: none !important; }

/* Login */
#login-screen { position: fixed; inset: 0; display: flex; align-items: center; justify-content: center; padding: 16px; }
.login-box { width: 100%; max-width: 320px; background: var(--bg-base); border: 1px solid var(--bd); border-radius: var(--r-l); padding: 28px 24px; text-align: center; box-shadow: var(--sh-md); }
.login-logo { width: 40px; height: 40px; border-radius: 10px; margin: 0 auto 12px; background: linear-gradient(135deg, var(--accent), var(--accent-h)); color: #fff; display: flex; align-items: center; justify-content: center; font-weight: 800; }
.login-title { font-size: 18px; font-weight: 700; margin: 0 0 4px; }
.login-sub { font-size: 13px; color: var(--tx-2); margin: 0 0 18px; }
.btn-google { width: 100%; display: flex; align-items: center; justify-content: center; gap: 8px; background: var(--bg-elevated); border: 1px solid var(--bd-m); color: var(--tx-1); padding: 10px; border-radius: var(--r-m); font-size: 13.5px; font-weight: 600; cursor: pointer; }
.btn-google:hover { background: var(--bg-surface); }
.login-divider { color: var(--tx-3); font-size: 11px; margin: 14px 0; display: flex; align-items: center; gap: 8px; }
.login-divider::before, .login-divider::after { content: ""; flex: 1; height: 1px; background: var(--bd-m); }
.login-field { text-align: left; margin-bottom: 10px; }
.login-label { display: block; font-size: 11.5px; color: var(--tx-2); margin-bottom: 3px; }
.login-input { width: 100%; background: var(--bg-input); border: 1px solid var(--bd-m); color: var(--tx-1); padding: 8px 10px; border-radius: var(--r-m); font-size: 13px; font-family: inherit; }
.login-err { color: var(--err); font-size: 12px; min-height: 14px; margin: 4px 0; }
.btn-login-main { width: 100%; background: var(--accent); color: #05100a; border: none; padding: 9px; border-radius: var(--r-m); font-size: 13.5px; font-weight: 700; cursor: pointer; margin-top: 4px; }
.btn-login-main:hover { background: var(--accent-h); }

/* App shell */
#app { display: flex; height: 100vh; }
.sidebar { width: var(--sidebar-w); background: var(--bg-base); border-right: 1px solid var(--bd); display: flex; flex-direction: column; padding: 16px 12px; flex-shrink: 0; }
.brand { display: flex; align-items: center; gap: 10px; padding: 0 4px 20px; }
.brand-mark { width: 32px; height: 32px; border-radius: 8px; background: linear-gradient(135deg, var(--accent), var(--accent-h)); color: #fff; display: flex; align-items: center; justify-content: center; font-weight: 800; font-size: 13px; flex-shrink: 0; }
.brand-name { font-weight: 700; font-size: 14px; }
.brand-sub { font-size: 11px; color: var(--tx-3); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; max-width: 160px; }
.nav { display: flex; flex-direction: column; gap: 2px; }
.nav-item { text-align: left; background: transparent; border: none; color: var(--tx-2); padding: 9px 12px; border-radius: var(--r-m); font-size: 13.5px; cursor: pointer; }
.nav-item:hover { background: var(--bg-elevated); color: var(--tx-1); }
.nav-item.active { background: var(--accent-g2); color: var(--accent-h); font-weight: 600; }
.sidebar-footer { margin-top: auto; display: flex; align-items: center; justify-content: space-between; padding: 8px 4px; }
.theme-toggle { width: 38px; height: 21px; border-radius: var(--r-f); background: var(--bg-elevated); border: 1px solid var(--bd-m); cursor: pointer; position: relative; }
.theme-toggle .knob { position: absolute; top: 2px; left: 2px; width: 15px; height: 15px; border-radius: 50%; background: var(--accent); transition: transform var(--t); }
[data-theme="light"] .theme-toggle .knob { transform: translateX(17px); }
.logout-btn { background: transparent; border: 1px solid var(--bd-m); color: var(--tx-2); font-size: 12px; padding: 6px 10px; border-radius: var(--r-m); cursor: pointer; }
.logout-btn:hover { color: var(--tx-1); border-color: var(--accent); }

.main { flex: 1; overflow-y: auto; padding: 28px 32px; }
.tab-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 18px; }
.tab-header h2, .tab-header h3 { margin: 0; font-size: 19px; }
.tab-header h4 { margin: 0 0 10px; font-size: 14px; color: var(--tx-2); }

.btn-primary { background: var(--accent); color: #05100a; border: none; padding: 9px 16px; border-radius: var(--r-m); font-size: 13.5px; font-weight: 700; cursor: pointer; }
.btn-primary:hover { background: var(--accent-h); }
.btn-secondary { background: transparent; border: 1px solid var(--bd-m); color: var(--tx-1); padding: 8px 14px; border-radius: var(--r-m); font-size: 13px; cursor: pointer; }
.btn-secondary:hover { border-color: var(--accent); }

.card-list { display: flex; flex-direction: column; gap: 8px; }
.card { background: var(--bg-base); border: 1px solid var(--bd); border-radius: var(--r-m); padding: 14px 16px; display: flex; align-items: center; justify-content: space-between; gap: 12px; }
.card-main { min-width: 0; }
.card-title { font-weight: 600; font-size: 14px; margin-bottom: 2px; }
.card-sub { font-size: 12px; color: var(--tx-3); font-family: ui-monospace, monospace; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.card-actions { display: flex; gap: 8px; flex-shrink: 0; align-items: center; }
.badge { font-size: 11px; padding: 3px 9px; border-radius: var(--r-f); font-weight: 600; }
.badge.active { background: var(--accent-g2); color: var(--accent-h); }
.badge.blocked { background: rgba(240,101,121,.15); color: var(--err); }
.icon-btn { background: transparent; border: 1px solid var(--bd-m); color: var(--tx-2); cursor: pointer; padding: 6px 10px; border-radius: var(--r-s); font-size: 12px; }
.icon-btn:hover { color: var(--tx-1); border-color: var(--accent); }
.empty-msg { color: var(--tx-3); font-size: 13px; padding: 20px 0; text-align: center; }

.split { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.msg-list { display: flex; flex-direction: column; gap: 8px; max-height: 60vh; overflow-y: auto; }
.msg-item { background: var(--bg-base); border: 1px solid var(--bd); border-radius: var(--r-m); padding: 10px 12px; font-size: 13px; }
.msg-author { font-weight: 600; font-size: 12px; color: var(--accent-h); margin-bottom: 3px; }
.msg-time { font-size: 10.5px; color: var(--tx-3); float: right; }
.msg-content { white-space: pre-wrap; word-break: break-word; }

@media (max-width: 800px) {
  .sidebar { display: none; }
  .split { grid-template-columns: 1fr; }
}