@import url('https://fonts.googleapis.com/css2?family=Instrument+Serif:ital@0;1&family=DM+Sans:ital,opsz,wght@0,9..40,300;0,9..40,400;0,9..40,500;1,9..40,300&display=swap');

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --ink: #18181b;
  --ink2: #52525b;
  --ink3: #a1a1aa;
  --ink4: #d4d4d8;
  --surface: #ffffff;
  --surface2: #fafaf9;
  --surface3: #f4f4f5;
  --surface4: #e4e4e7;
  --accent: #4f6ef7;
  --accent-soft: #eef0fe;
  --accent-border: rgba(79,110,247,.2);
  --green: #16a34a;
  --green-soft: #f0fdf4;
  --green-border: rgba(22,163,74,.2);
  --amber: #d97706;
  --amber-soft: #fffbeb;
  --amber-border: rgba(217,119,6,.2);
  --red: #dc2626;
  --red-soft: #fef2f2;
  --red-border: rgba(220,38,38,.2);
  --purple: #7c3aed;
  --purple-soft: #f5f3ff;
  --purple-border: rgba(124,58,237,.2);
  --border: rgba(0,0,0,0.07);
  --border2: rgba(0,0,0,0.11);
  --shadow-sm: 0 1px 3px rgba(0,0,0,.06), 0 1px 2px rgba(0,0,0,.04);
  --shadow: 0 4px 16px rgba(0,0,0,.07), 0 2px 4px rgba(0,0,0,.04);
  --r: 14px;
  --r-sm: 9px;
  --font: 'DM Sans', sans-serif;
  --serif: 'Instrument Serif', serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --ink: #fafafa;
    --ink2: #a1a1aa;
    --ink3: #71717a;
    --ink4: #3f3f46;
    --surface: #111113;
    --surface2: #18181b;
    --surface3: #1f1f23;
    --surface4: #27272a;
    --accent: #818cf8;
    --accent-soft: #1e1b4b;
    --accent-border: rgba(129,140,248,.22);
    --green: #4ade80;
    --green-soft: #052e16;
    --green-border: rgba(74,222,128,.2);
    --amber: #fbbf24;
    --amber-soft: #1c1400;
    --amber-border: rgba(251,191,36,.2);
    --red: #f87171;
    --red-soft: #1f0a0a;
    --red-border: rgba(248,113,113,.2);
    --purple: #a78bfa;
    --purple-soft: #1e1033;
    --purple-border: rgba(167,139,250,.2);
    --border: rgba(255,255,255,0.07);
    --border2: rgba(255,255,255,0.11);
    --shadow-sm: 0 1px 4px rgba(0,0,0,.4);
    --shadow: 0 4px 16px rgba(0,0,0,.4);
  }
}

html, body { height: 100%; }
body { font-family: var(--font); color: var(--ink); background: var(--surface); line-height: 1.5; font-size: 14px; -webkit-font-smoothing: antialiased; }

/* ── AUTH PAGE ── */
.auth-page { background: var(--surface2); min-height: 100vh; }
.auth-split { display: grid; grid-template-columns: 1fr 1fr; min-height: 100vh; }

.auth-brand {
  background: var(--ink);
  display: flex; align-items: center; justify-content: center;
  padding: 64px 56px; position: relative; overflow: hidden;
}
.auth-brand::before {
  content: ''; position: absolute;
  width: 520px; height: 520px; border-radius: 50%;
  background: radial-gradient(circle, rgba(79,110,247,.18) 0%, transparent 70%);
  top: -160px; right: -160px;
}
.auth-brand::after {
  content: ''; position: absolute;
  width: 380px; height: 380px; border-radius: 50%;
  background: radial-gradient(circle, rgba(124,58,237,.12) 0%, transparent 70%);
  bottom: -90px; left: -90px;
}
.auth-brand-inner { position: relative; z-index: 1; max-width: 400px; width: 100%; }

.brand-logo { display: flex; align-items: center; gap: 10px; margin-bottom: 52px; }
.brand-mark { font-size: 22px; color: #818cf8; }
.brand-name { font-family: var(--serif); font-size: 24px; color: #fafafa; }

.brand-tagline {
  font-family: var(--serif); font-size: 44px; font-weight: 400;
  line-height: 1.12; color: #fafafa; margin-bottom: 44px; letter-spacing: -.5px;
}
.brand-tagline em { color: #818cf8; font-style: italic; }

.brand-features { display: flex; flex-direction: column; gap: 16px; margin-bottom: 44px; }
.brand-feat { display: flex; align-items: center; gap: 12px; font-size: 13px; color: #71717a; }
.feat-icon { color: #818cf8; font-size: 11px; width: 18px; text-align: center; }
.brand-note { font-size: 11px; color: #3f3f46; }

.auth-form-panel {
  display: flex; align-items: center; justify-content: center;
  padding: 48px 32px; background: var(--surface);
}
.auth-form-wrap { width: 100%; max-width: 390px; }

.auth-tabs {
  display: flex; gap: 2px; background: var(--surface3);
  border-radius: 10px; padding: 3px; margin-bottom: 36px;
}
.auth-tab {
  flex: 1; padding: 8px 12px; border: none;
  background: none; border-radius: 8px;
  font-family: var(--font); font-size: 13px; cursor: pointer;
  color: var(--ink3); transition: all .15s;
}
.auth-tab.active {
  background: var(--surface); color: var(--ink);
  font-weight: 500; box-shadow: var(--shadow-sm);
}

.auth-form { display: none; }
.auth-form.active { display: block; }
.form-title { font-family: var(--serif); font-size: 28px; font-weight: 400; color: var(--ink); margin-bottom: 4px; }
.form-sub { font-size: 13px; color: var(--ink3); margin-bottom: 28px; }

.field-group { display: flex; flex-direction: column; gap: 5px; margin-bottom: 14px; }
.field-group label { font-size: 12px; font-weight: 500; color: var(--ink2); }
.field-row { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }

input[type=text], input[type=email], input[type=password],
input[type=date], select, textarea {
  width: 100%; padding: 9px 12px;
  border: 1px solid var(--border2); border-radius: var(--r-sm);
  background: var(--surface); color: var(--ink);
  font-family: var(--font); font-size: 13px;
  outline: none; transition: border-color .15s, box-shadow .15s; appearance: none;
}
input:focus, select:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(79,110,247,.1);
}
select {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='10' height='6'%3E%3Cpath fill='%23a1a1aa' d='M5 6L0 0h10z'/%3E%3C/svg%3E");
  background-repeat: no-repeat; background-position: right 11px center; padding-right: 28px;
}

.btn-primary {
  width: 100%; padding: 10px 16px;
  background: var(--ink); color: var(--surface);
  border: none; border-radius: var(--r-sm);
  font-family: var(--font); font-size: 13px; font-weight: 500;
  cursor: pointer; transition: opacity .15s; margin-top: 4px;
}
.btn-primary:hover { opacity: .82; }

.btn-secondary {
  padding: 7px 13px; background: none; color: var(--ink2);
  border: 1px solid var(--border2); border-radius: var(--r-sm);
  font-family: var(--font); font-size: 12px;
  cursor: pointer; transition: all .15s;
}
.btn-secondary:hover { background: var(--surface3); color: var(--ink); }

.btn-accent {
  padding: 7px 13px; background: var(--accent-soft); color: var(--accent);
  border: 1px solid var(--accent-border); border-radius: var(--r-sm);
  font-family: var(--font); font-size: 12px; font-weight: 500;
  cursor: pointer; transition: all .15s;
}
.btn-accent:hover { background: var(--accent); color: #fff; }

.btn-danger {
  padding: 7px 13px; background: none; color: var(--red);
  border: 1px solid var(--red-border); border-radius: var(--r-sm);
  font-family: var(--font); font-size: 12px; cursor: pointer; transition: all .15s;
}
.btn-danger:hover { background: var(--red-soft); }

.form-switch { font-size: 12px; color: var(--ink3); text-align: center; margin-top: 18px; }
.form-switch a { color: var(--accent); text-decoration: none; }

.demo-box {
  margin-top: 22px; padding: 16px;
  background: var(--surface2); border-radius: var(--r-sm);
  text-align: center; border: 1px solid var(--border);
}
.demo-label { font-size: 11px; color: var(--ink3); margin-bottom: 10px; letter-spacing: .4px; text-transform: uppercase; font-weight: 500; }
.btn-demo {
  padding: 8px 18px; background: var(--accent-soft); color: var(--accent);
  border: 1px solid var(--accent-border); border-radius: var(--r-sm);
  font-family: var(--font); font-size: 12px; font-weight: 500;
  cursor: pointer; transition: all .15s;
}
.btn-demo:hover { background: var(--accent); color: #fff; }

.form-error {
  background: var(--red-soft); color: var(--red);
  padding: 9px 12px; border-radius: var(--r-sm); font-size: 12px;
  margin-bottom: 12px; border: 1px solid var(--red-border);
}
.form-success {
  background: var(--green-soft); color: var(--green);
  padding: 9px 12px; border-radius: var(--r-sm); font-size: 12px;
  margin-bottom: 12px; border: 1px solid var(--green-border);
}
.hidden { display: none !important; }

@media (max-width: 768px) {
  .auth-split { grid-template-columns: 1fr; }
  .auth-brand { display: none; }
}