:root {
  --bg-image: url('../assets/background.jpg');
  --overlay: rgba(255,255,255,0.1);
  --card-bg: rgba(255,255,255,0.15);
  --accent1: #ff8c00;
  --accent2: #ff0066;
  --text: #ffffffdd;
  --input-bg: rgba(255,255,255,0.2);
  --placeholder: #ffffff88;
  --radius: 16px;
  --gap: 1rem;
  --trans-speed: 0.5s;
  --font: Poppins, sans-serif;
  --max-w: 280px;
}

*{box-sizing:border-box;margin:0;padding:0}
html,body{height:100%;font-family:var(--font);background:var(--bg-image) center/cover no-repeat;display:flex;align-items:center;justify-content:center}
.frame{width:min(85vmin,450px);aspect-ratio:1;background:var(--overlay);border-radius:var(--radius);backdrop-filter:blur(12px);box-shadow:0 8px 32px rgba(0,0,0,0.6);display:flex;align-items:center;justify-content:center;padding:var(--gap)}
.card{width:100%;background:var(--card-bg);backdrop-filter:blur(8px);border-radius:calc(var(--radius)/1.2);padding:calc(var(--gap)*1.2);color:var(--text);text-align:center;box-shadow:0 4px 24px rgba(0,0,0,0.4);transition:transform var(--trans-speed) ease}
.card.switching{transform:translateY(-8px)}
.logo{font-size:1.8rem;font-weight:700;background:linear-gradient(60deg,var(--accent1),var(--accent2));-webkit-background-clip:text;-webkit-text-fill-color:transparent;margin-bottom:var(--gap)}
.online{font-size:0.8rem;margin-bottom:calc(var(--gap)*1.2);color:var(--text);letter-spacing:1px}
.forms{position:relative;overflow:hidden;transition:height var(--trans-speed) ease;height:220px}
form{position:absolute;inset:0;display:flex;flex-direction:column;align-items:center;gap:var(--gap);transition:opacity var(--trans-speed) ease,transform var(--trans-speed) ease}
.hidden{opacity:0;transform:translateY(-20px) scale(.95);pointer-events:none}
input{width:95%;max-width:var(--max-w);padding:.7rem;background:var(--input-bg);border:none;border-radius:var(--radius);color:var(--text);font-size:.95rem;backdrop-filter:blur(4px)}
input::placeholder{color:var(--placeholder)}
.checkbox{display:flex;align-items:center;gap:.4rem;font-size:.85rem;cursor:pointer;color:var(--text);user-select:none}
.checkbox input{display:none}
.box{width:16px;height:16px;border:2px solid var(--text);border-radius:4px;position:relative;transition:background var(--trans-speed),border-color var(--trans-speed)}
.checkbox input:checked+.box{background:var(--accent1);border-color:var(--accent1)}
.box::after{content:'';position:absolute;top:2px;left:5px;width:4px;height:8px;border:solid #fff;border-width:0 2px 2px 0;transform:rotate(45deg);opacity:0;transition:opacity var(--trans-speed)}
.checkbox input:checked+.box::after{opacity:1}
button{width:100%;max-width:var(--max-w);padding:.8rem;border:none;border-radius:var(--radius);background:linear-gradient(135deg,var(--accent1),var(--accent2));color:#fff;font-weight:600;font-size:.95rem;cursor:pointer;box-shadow:0 4px 16px rgba(0,0,0,0.4);transition:transform var(--trans-speed) ease,box-shadow var(--trans-speed) ease}
button:hover{transform:translateY(-2px);box-shadow:0 8px 24px rgba(0,0,0,0.5)}
button.guest{background:transparent;border:2px dashed var(--text);color:var(--text);margin-top:var(--gap);transition:transform var(--trans-speed) ease}
.card.switching button.guest{transform:translateY(12px)}
.switch{display:block;margin-top:calc(var(--gap)/2);font-size:.85rem;color:var(--text)}
.switch a{color:var(--accent2);text-decoration:none;font-weight:600;margin-left:.25rem;display:inline-block;transition:color var(--trans-speed),transform var(--trans-speed)}
.switch a:hover{color:var(--accent1); cursor: pointer;}
.switch a.back{animation:slideBack var(--trans-speed) ease}
@keyframes slideBack{from{opacity:0;transform:translateX(-20px)}to{opacity:1;transform:translateX(0)}}
#toasts{position:fixed;top:.5rem;left:50%;transform:translateX(-50%);width:min(100%,360px);display:flex;flex-direction:column;gap:.4rem;pointer-events:none;z-index:1000}
.toast{padding:.6rem .8rem;background:rgba(0,0,0,0.7);color:#fff;font-size:.85rem;border-left:4px solid var(--accent2);box-shadow:0 2px 8px rgba(0,0,0,0.5);position:relative;overflow:hidden}
.toast::before{content:'';position:absolute;bottom:0;left:0;height:3px;width:100%;background:var(--accent2);animation:progressBar calc(var(--trans-speed)*.9) linear forwards}
@keyframes progressBar{to{width:0}}
@media(max-width:600px){
  :root{--max-w:200px;--radius:12px;--gap:.6rem}
  .frame{width:93vmin;padding:var(--gap)}
  .logo{font-size:1.4rem}
  .online{font-size:.75rem}
  .forms{height:210px}
  input,button{font-size:.9rem;padding:.6rem}
  .switch{font-size:.9rem}
  .card.switching{transform:translateY(-4px) scale(.98)}
  .card.switching button.guest{transform:translateY(8px)}
}