/* 登录 / 注册页 —— 左右分栏 + 三套主题（light/warm/dark）。所有颜色走变量。 */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&family=Noto+Sans+SC:wght@400;500;700&display=swap');

:root,[data-theme="light"]{
  --c-bg:#F7F8FA; --c-surface:#ffffff; --c-surface2:#F0F2F7;
  --c-border:rgba(0,0,0,.08); --c-border2:rgba(0,0,0,.15);
  --c-accent:#5B56E8; --c-accent-h:#4A46D4; --c-green:#079769; --c-red:#d83a3a;
  --c-text:#14151A; --c-muted:#6b7081;
}
[data-theme="warm"]{
  --c-bg:#FFFDF8; --c-surface:#FFFFFF; --c-surface2:#F5F5F5;
  --c-border:#E0E0E0; --c-border2:#BDBDBD;
  --c-accent:#FFA726; --c-accent-h:#FB8C00; --c-green:#4CAF50; --c-red:#F44336;
  --c-text:#333333; --c-muted:#666666;
}
[data-theme="dark"]{
  --c-bg:#0A0A0F; --c-surface:#14151f; --c-surface2:#1e1f2e;
  --c-border:rgba(255,255,255,.08); --c-border2:rgba(255,255,255,.15);
  --c-accent:#6C63FF; --c-accent-h:#5A52E5; --c-green:#10b98b; --c-red:#e05252;
  --c-text:#e2e4f0; --c-muted:#8b90a0;
}

*{box-sizing:border-box}
html,body{height:100%}
body{margin:0;height:100vh;overflow:hidden;
  font-family:'Inter','PingFang SC','Noto Sans SC','Noto Sans KR',system-ui,sans-serif;
  background:var(--c-bg);color:var(--c-text);-webkit-font-smoothing:antialiased}

.split-layout{display:flex;height:100vh}

/* 左：品牌区 */
.pane-left{flex:1;position:relative;overflow:hidden;display:flex;flex-direction:column;
  justify-content:center;align-items:flex-start;padding:64px 72px;color:#fff;
  background:linear-gradient(135deg,var(--c-accent),#8a82ff)}
.pane-left::before{content:"";position:absolute;inset:0;pointer-events:none;
  background:radial-gradient(circle at 28% 18%,rgba(255,255,255,.28),transparent 52%)}
.pane-left::after{content:"";position:absolute;right:-90px;bottom:-90px;width:380px;height:380px;
  border-radius:42% 58% 60% 40%/45% 45% 55% 55%;background:rgba(255,255,255,.08);pointer-events:none}
.brand-logo{height:40px;margin-bottom:26px;position:relative}
.brand-title{font-size:52px;font-weight:800;letter-spacing:-1.5px;margin:0 0 18px;position:relative}
.brand-desc{font-size:18px;font-weight:500;opacity:.9;max-width:420px;line-height:1.7;margin:0;position:relative}

/* 右：表单区 */
.pane-right{flex:1;background:var(--c-surface);overflow-y:auto;display:flex;position:relative;
  box-shadow:-10px 0 30px rgba(0,0,0,.05)}
.form-container{margin:auto;width:100%;max-width:400px;padding:40px}
.auth-title{font-size:26px;font-weight:800;letter-spacing:-.5px;margin:0 0 6px}
.auth-sub{color:var(--c-muted);font-size:14px;margin:0 0 26px}

label{display:block;font-size:13px;font-weight:600;margin:0 0 6px;color:var(--c-text)}
input,select{width:100%;background:var(--c-bg);border:1px solid var(--c-border);border-radius:12px;
  padding:15px 16px;font-size:15px;color:var(--c-text);font-family:inherit;
  box-shadow:0 1px 2px rgba(0,0,0,.02) inset;transition:border-color .2s,box-shadow .2s,background .2s}
input::placeholder{color:var(--c-muted);opacity:.7}
input:focus,select:focus{outline:none;border-color:var(--c-accent);background:var(--c-surface);
  box-shadow:0 0 0 3px color-mix(in srgb,var(--c-accent) 16%,transparent)}
.field{margin-bottom:16px}

.btn-login,.btn-primary{width:100%;border:none;cursor:pointer;color:#fff;font-weight:700;font-size:15px;
  border-radius:12px;padding:15px;font-family:inherit;margin-top:4px;
  background:linear-gradient(135deg,var(--c-accent),var(--c-accent-h));
  box-shadow:0 6px 20px color-mix(in srgb,var(--c-accent) 30%,transparent);
  transition:transform .15s,box-shadow .2s,filter .2s}
.btn-login:hover,.btn-primary:hover{transform:translateY(-1px);filter:brightness(1.05);
  box-shadow:0 10px 26px color-mix(in srgb,var(--c-accent) 40%,transparent)}
.btn-login:active,.btn-primary:active{transform:translateY(0)}

.btn-dd{width:100%;border:none;cursor:pointer;color:#fff;font-weight:700;font-size:15px;border-radius:12px;
  padding:15px;font-family:inherit;background:linear-gradient(135deg,#1AABF0,#1593D1);
  box-shadow:0 6px 20px rgba(26,171,240,.3);transition:transform .15s,filter .2s}
.btn-dd:hover{transform:translateY(-1px);filter:brightness(1.05)}

.divider{display:flex;align-items:center;gap:12px;color:var(--c-muted);font-size:12.5px;margin:18px 0}
.divider::before,.divider::after{content:"";flex:1;height:1px;background:var(--c-border)}

.error,.alert{border-radius:12px;padding:11px 14px;font-size:13px;margin-bottom:16px}
.error,.alert.err{background:color-mix(in srgb,var(--c-red) 12%,transparent);
  border:1px solid color-mix(in srgb,var(--c-red) 32%,transparent);color:var(--c-red)}
.alert.ok{background:color-mix(in srgb,var(--c-green) 12%,transparent);
  border:1px solid color-mix(in srgb,var(--c-green) 32%,transparent);color:var(--c-green)}

.register-link,.back{text-align:center;color:var(--c-muted);font-size:13px;margin-top:20px}
.register-link a,.back a{color:var(--c-accent);font-weight:600;text-decoration:none}
.register-link a:hover,.back a:hover{text-decoration:underline}

.theme-toggle{position:absolute;top:20px;right:20px;width:38px;height:38px;border-radius:10px;
  border:1px solid var(--c-border);background:var(--c-surface2);color:var(--c-text);cursor:pointer;
  font-size:16px;display:flex;align-items:center;justify-content:center;transition:background .2s}
.theme-toggle:hover{border-color:var(--c-border2)}

/* 注册身份分段（自包含：选中=白底高亮+过渡，稳健不依赖额外元素） */
.auth-tabs{display:flex;gap:6px;background:var(--c-surface2);border:1px solid var(--c-border);
  padding:5px;border-radius:12px;margin-bottom:22px}
.auth-tabs button{flex:1;border:none;cursor:pointer;font-family:inherit;text-align:center;
  padding:11px 8px;border-radius:9px;font-size:14px;font-weight:600;color:var(--c-muted);background:transparent;
  transition:background .25s var(--ae,cubic-bezier(.2,.8,.2,1)),color .2s,box-shadow .25s}
.auth-tabs button:hover{color:var(--c-text)}
.auth-tabs button.active{background:var(--c-surface);color:var(--c-accent);box-shadow:0 2px 8px rgba(0,0,0,.1)}

/* 身份切换：内容淡入上滑特效 */
@keyframes regIn{from{opacity:0;transform:translateY(10px)}to{opacity:1;transform:none}}
.reg-anim{animation:regIn .3s cubic-bezier(.2,.8,.2,1) both}

/* 注册页：标签左 / 输入右 / 提示下（Grid） */
.reg input,.reg select{border-radius:10px;padding:11px 14px;font-size:14px}
.form-group{display:grid;grid-template-columns:78px 1fr;align-items:center;gap:5px 12px;margin-bottom:14px}
.form-group label{text-align:right;margin:0}
.form-group input,.form-group select{margin:0}
.form-group .help{grid-column:2;font-size:11.5px;color:var(--c-muted);line-height:1.4;margin:0}
.form-group .help.req{color:var(--c-red);font-weight:600}

/* 断点 */
@media(max-width:960px){
  .pane-left{display:none}
  .pane-right{background:var(--c-bg);box-shadow:none}
  .form-container{border:1px solid var(--c-border);border-radius:24px;background:var(--c-surface);
    padding:40px;box-shadow:0 12px 44px rgba(0,0,0,.07)}
  .theme-toggle{position:fixed}
}
@media(max-width:480px){
  .form-container{max-width:100%;padding:28px 20px}
  .auth-title{font-size:22px}
  .reg .form-group{grid-template-columns:1fr}
  .reg .form-group label{text-align:left}
  .reg .form-group .help{grid-column:1}
}