/* ============================================================
   Checkers — Auth (sign in / register) · split page
   loads after checkers-dark.css
   ============================================================ */
body.auth{overflow:auto}
.auth-page{display:grid;grid-template-columns:1fr 1.05fr;min-height:100dvh}

/* ---------- form side ---------- */
.auth-form-side{display:flex;flex-direction:column;padding:34px 40px;position:relative}
.auth-form-side::before{content:"";position:absolute;inset:0;pointer-events:none;
  background:radial-gradient(700px 320px at 20% -120px, rgba(46,99,161,.16), transparent 70%)}
.af-brand{display:flex;align-items:center;gap:11px;position:relative;z-index:1}
.af-brand .mark{width:38px;height:38px;border-radius:11px;background:#efe3d4;display:grid;place-items:center;
  box-shadow:inset 0 0 0 1px #e2d3bf;flex:0 0 auto}
.af-brand .disc{position:relative;width:27px;height:27px;border-radius:50%;background:#1c4266;display:grid;place-items:center}
.af-brand .disc::after{content:"";position:absolute;width:22px;height:22px;border-radius:50%;border:3px solid #3a6690}
.af-brand .cr{position:relative;z-index:1;width:16px;height:12px;color:#f9cd11}
.af-brand .wm{font-family:var(--font-head);font-weight:800;font-size:20px;color:#fff;letter-spacing:-.015em}
.af-brand .wm b{color:var(--blue-link)}

.auth-card{margin:auto;width:100%;max-width:392px;position:relative;z-index:1;padding:34px 0}
.auth-card h1{font-family:var(--font-head);font-weight:800;font-size:27px;color:#fff;margin:0 0 4px;letter-spacing:-.01em}
.auth-card .sub{font-family:var(--font-body);font-size:14px;color:var(--text-3);margin:0 0 22px}

.af-tabs{display:flex;gap:0;background:var(--inset);border:1px solid var(--border);border-radius:9px;padding:3px;margin-bottom:22px}
.af-tabs button{flex:1;padding:10px;font-family:var(--font-head);font-weight:700;font-size:14px;color:var(--text-2);border-radius:6px}
.af-tabs button.on{background:var(--panel-3);color:#fff;box-shadow:0 1px 0 rgba(0,0,0,.3)}

.af-form{display:flex;flex-direction:column;gap:15px}
.af-field{display:flex;flex-direction:column;gap:7px}
.af-field label{font-family:var(--font-head);font-weight:600;font-size:12px;letter-spacing:.04em;
  text-transform:uppercase;color:var(--text-3)}
.af-input-wrap{position:relative}
.af-input{width:100%;background:var(--inset);border:1px solid var(--border-2);border-radius:8px;
  padding:12px 13px;font-family:var(--font-body);font-size:14.5px;color:var(--text);outline:none}
.af-input::placeholder{color:var(--text-3)}
.af-input:focus{border-color:var(--blue)}
.af-eye{position:absolute;right:8px;top:50%;transform:translateY(-50%);width:32px;height:32px;border-radius:7px;
  display:grid;place-items:center;color:var(--text-3)}
.af-eye:hover{color:var(--text-2);background:var(--panel-2)}
.af-row{display:flex;align-items:center;justify-content:space-between;gap:10px}
.af-check{display:flex;align-items:center;gap:8px;font-family:var(--font-body);font-size:13px;color:var(--text-2);cursor:pointer}
.af-check input{width:16px;height:16px;accent-color:var(--blue)}
.af-link{font-family:var(--font-head);font-weight:700;font-size:13px;color:var(--blue-link);cursor:pointer}
.af-link:hover{text-decoration:underline}
.af-hint{font-family:var(--font-body);font-size:12px;color:var(--text-3);margin-top:-4px}
.af-alert{font-family:var(--font-body);font-size:13px;line-height:1.4;color:#ffd6d6;background:rgba(190,57,44,.14);
  border:1px solid rgba(190,57,44,.45);border-radius:8px;padding:10px 12px}
.af-alert[hidden]{display:none}
.auth-card button:disabled{opacity:.62;cursor:wait}

.af-divider{display:flex;align-items:center;gap:12px;margin:4px 0}
.af-divider::before,.af-divider::after{content:"";flex:1;height:1px;background:var(--border)}
.af-divider span{font-family:var(--font-body);font-size:12px;color:var(--text-3)}

.af-oauth{display:flex;align-items:center;justify-content:center;gap:10px;width:100%;
  background:var(--panel-2);border:1px solid var(--border-2);border-radius:9px;padding:12px;
  font-family:var(--font-head);font-weight:700;font-size:14.5px;color:var(--text)}
.af-oauth:hover{border-color:#43596d;background:var(--panel-3)}
.af-oauth svg{width:18px;height:18px;flex:0 0 auto}

.af-switch{font-family:var(--font-body);font-size:13.5px;color:var(--text-3);text-align:center;margin-top:18px}
.af-switch b{color:var(--blue-link);font-family:var(--font-head);font-weight:700;cursor:pointer}
.af-switch b:hover{text-decoration:underline}

.af-legal{font-family:var(--font-fine);font-size:11.5px;color:var(--text-3);line-height:1.5;margin-top:14px;text-align:center}
.af-legal a{color:var(--text-2);text-decoration:underline}

.register-only{display:none}
body.mode-register .register-only{display:flex}
body.mode-register .signin-only{display:none}

/* ---------- brand side ---------- */
.auth-brand-side{background:var(--bg-2);border-left:1px solid var(--border);
  display:flex;flex-direction:column;align-items:center;justify-content:center;gap:26px;padding:48px;position:relative;overflow:hidden}
.auth-brand-side::before{content:"";position:absolute;inset:0;pointer-events:none;
  background:radial-gradient(680px 460px at 70% 12%, rgba(46,99,161,.28), transparent 66%)}
.abs-board{width:300px;max-width:62%;position:relative;z-index:1}
.abs-board .board{aspect-ratio:1;display:grid;grid-template-columns:repeat(8,1fr);grid-template-rows:repeat(8,1fr);
  border-radius:var(--r-board);overflow:hidden;box-shadow:0 26px 56px -16px rgba(0,0,0,.75),inset 0 0 0 1px rgba(0,0,0,.22)}
.abs-board .sq.dark{background:var(--board-brown)}
.abs-board .sq.light{background:var(--board-cream)}
.abs-board .sq{display:grid;place-items:center}
.abs-board .pc{width:78%;height:78%;border-radius:50%;box-shadow:1px 2px 4px rgba(0,0,0,.45);position:relative}
.abs-board .pc::after{content:"";position:absolute;top:19%;left:19%;width:62%;height:62%;border-radius:50%;border:3px solid currentColor;opacity:.55}
.abs-board .pc.black{background:var(--piece-black);color:var(--piece-black-in)}
.abs-board .pc.white{background:var(--piece-white);color:var(--piece-white-in)}
.abs-copy{position:relative;z-index:1;text-align:center;max-width:340px}
.abs-copy h2{font-family:var(--font-head);font-weight:800;font-size:26px;color:#fff;margin:0;line-height:1.2;letter-spacing:-.01em}
.abs-copy p{font-family:var(--font-body);font-size:14px;color:var(--text-2);margin:10px 0 0;line-height:1.5}
.abs-variants{display:flex;flex-wrap:wrap;justify-content:center;gap:7px;margin-top:18px}
.abs-variants .v{font-family:var(--font-head);font-weight:700;font-size:12.5px;color:var(--text-2);
  background:var(--panel);border:1px solid var(--border);border-radius:var(--r-pill);padding:6px 13px}

@media(max-width:900px){
  .auth-page{grid-template-columns:1fr}
  .auth-brand-side{display:none}
  .auth-form-side{padding:26px 22px}
}