/* Sign-in and sign-up pages. Same tokens and fonts as the home page; one dark theme. */
:root {
  --ink: #070A12; --deep: #0D1222; --raised: #141A2E; --line: #212943; --line-strong: #323C5E;
  --paper: #E8ECF6; --fog: #8C95AE; --dim: #5A6280;
  --signal: #7FA6FF; --signal-deep: #5B86FF; --on-signal: #060A16; --danger: #FF7B85; --warn: #F5C56B;
  --mark-top: #7FA6FF; --mark-left: #E8ECF6; --mark-right: #8C95AE; --mark-hole: #070A12; --danger-bg: #1a0f18; --danger-line: #5a2a35; --success: #4ADE9F;
  --font: "Archivo", "Helvetica Neue", Arial, system-ui, sans-serif;
  color-scheme: dark;
}

:root[data-theme='light'] {
  --ink: #F2F4F9; --deep: #FFFFFF; --raised: #E8ECF4; --line: #D6DCE8; --line-strong: #B9C2D6;
  --paper: #0E1426; --fog: #4B5570; --dim: #6A7390;
  --signal: #2D5BE3; --signal-deep: #1F47C2; --on-signal: #FFFFFF; --danger: #C2313F; --warn: #8A5A00; --success: #13804F;
  --danger-bg: #FBEAEC; --danger-line: #E8B4BA;
  --mark-top: #2D5BE3; --mark-left: #0E1426; --mark-right: #4B5570; --mark-hole: #F2F4F9;
  color-scheme: light;
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0; min-height: 100vh; min-height: 100dvh; background: var(--ink); color: var(--paper); font-family: var(--font);
  font-size: 1.0625rem; line-height: 1.5; -webkit-font-smoothing: antialiased; display: flex; flex-direction: column;
}
a { color: var(--signal); }
a:hover { color: var(--paper); }
:focus-visible { outline: 2px solid var(--signal); outline-offset: 2px; }
[hidden] { display: none !important; }
.wrap { width: 100%; max-width: 1240px; margin: 0 auto; padding: 0 max(16px, env(safe-area-inset-left, 0px)); }
/* ---------- header (shared look, docs/design/visual-system.md) ---------- */
.top { position: sticky; top: 0; z-index: 20; background: var(--ink); border-bottom: 1px solid var(--line); }
.top .wrap { display: flex; align-items: center; gap: 16px; min-height: 64px; padding-block: 0; max-width: 1240px; }
.brand { display: inline-flex; align-items: center; gap: 10px; text-decoration: none; color: var(--paper); font-weight: 800; font-stretch: 125%; font-size: 1.25rem; letter-spacing: -0.01em; }
.brand svg { width: 28px; height: 28px; }
.nav { position: relative; display: flex; align-self: stretch; gap: 28px; margin-left: 24px; font-weight: 500; font-size: 0.95rem; }
.nav a { display: flex; align-items: center; text-decoration: none; color: var(--fog); }
.nav a:hover, .nav a[aria-current] { color: var(--paper); }
.rail { position: absolute; left: 0; bottom: 14px; width: 0; height: 4px; opacity: 0; pointer-events: none; transition: transform .25s ease, width .25s ease, opacity .2s;
  background: linear-gradient(var(--paper), var(--paper)) 0 0 / 4px 4px no-repeat, repeating-linear-gradient(90deg, var(--signal) 0 4px, transparent 4px 7px); }
.acct { display: flex; align-items: center; gap: 10px; margin-left: auto; }
.acct .signin { color: var(--fog); font-weight: 600; font-stretch: 108%; font-size: 0.95rem; text-decoration: none; padding: 8px 10px; border-radius: 10px; white-space: nowrap; }
.acct .signin:hover { color: var(--paper); }
.acct .btn { min-height: 40px; padding: 0 1.1em; font-size: 0.95rem; white-space: nowrap; }
.acct .demo-link { display: none; }
@media (min-width: 640px) { .acct .demo-link:not([hidden]) { display: inline-flex; } }
@media (max-width: 719px) {
  .top .wrap { flex-wrap: wrap; row-gap: 0; }
  .top .brand { min-height: 64px; }
  .nav { order: 3; flex: 0 0 100%; margin-left: 0; gap: 22px; min-height: 44px; overflow-x: auto; scrollbar-width: none; border-top: 1px solid var(--line); }
  .nav::-webkit-scrollbar { display: none; }
  .nav a { white-space: nowrap; }
  .rail { bottom: 6px; }
}
@media (max-width: 400px) { .brand { font-size: 1.1rem; } .brand svg { width: 24px; height: 24px; } .acct { gap: 4px; } .acct .signin { padding: 8px 6px; } .acct .btn { padding: 0 .9em; } }

main { flex: 1; display: grid; place-items: start center; padding: clamp(16px, 5vw, 56px) 16px 48px; }
.card { width: 100%; max-width: 440px; background: var(--deep); border: 1px solid var(--line); border-radius: 16px; padding: clamp(20px, 5vw, 32px); display: grid; gap: 18px; }
h1 { margin: 0; font-stretch: var(--wide); font-weight: 800; font-size: clamp(1.8rem, 7vw, 2.4rem); line-height: 1; letter-spacing: -0.03em; }
.lede { margin: 0; color: var(--fog); }
.notice { margin: 0; padding: 12px 14px; border: 1px solid var(--line); border-left: 3px solid var(--signal); border-radius: 10px; background: var(--deep); font-size: 0.95rem; }
.notice a { color: var(--signal); font-weight: 600; }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 10px; min-height: 44px; padding: 0 1.3em; border-radius: 10px;
  font: inherit; font-weight: 600; font-stretch: 108%; font-size: 1rem; text-decoration: none; cursor: pointer;
  border: 1px solid var(--line-strong); background: transparent; color: var(--paper); transition: background-color .15s, border-color .15s;
}
.btn:hover { border-color: var(--fog); color: var(--paper); }
.btn-primary { background: var(--signal); border-color: var(--signal); color: var(--on-signal); }
.btn-primary:hover { background: var(--signal-deep); border-color: var(--signal-deep); color: var(--on-signal); }
.btn[aria-disabled="true"] { opacity: .6; cursor: progress; }
.btn { width: 100%; }
.top .btn, .acct .btn { width: auto; }
.social { display: grid; gap: 10px; }
.social-btn svg { width: 22px; height: 22px; flex: none; }

.or { display: flex; align-items: center; gap: 12px; color: var(--fog); font-size: 0.875rem; margin: 0; }
.or::before, .or::after { content: ""; flex: 1; height: 1px; background: var(--line); }

form { display: grid; gap: 16px; }
.field { display: grid; gap: 6px; }
label { font-weight: 650; font-size: 0.95rem; }
.hint { color: var(--fog); font-size: 0.85rem; margin: 0; }
input[type="text"], input[type="password"] {
  width: 100%; min-height: 48px; padding: 0 14px; border-radius: 10px; border: 1px solid var(--line-strong); background: var(--deep); color: var(--paper);
  font: inherit; font-size: 1rem;
}
input:focus-visible { outline: 2px solid var(--signal); outline-offset: 2px; border-color: var(--signal); }
.pw { display: grid; grid-template-columns: 1fr auto; gap: 8px; align-items: center; }
.toggle { min-height: 48px; padding: 0 14px; border-radius: 10px; border: 1px solid var(--line-strong); background: transparent; color: var(--fog); font: inherit; font-weight: 650; cursor: pointer; }
.toggle:hover { color: var(--paper); border-color: var(--fog); }
.check { display: grid; grid-template-columns: auto 1fr; gap: 10px; align-items: start; font-weight: 500; font-size: 0.95rem; }
.check input { width: 22px; height: 22px; margin: 1px 0 0; accent-color: var(--signal); }
.rules { margin: 0; padding-left: 1.1em; color: var(--fog); font-size: 0.875rem; display: grid; gap: 2px; }

.msg { margin: 0; min-height: 0; font-size: 0.95rem; }
.msg.error { color: var(--danger); padding: 10px 12px; border: 1px solid var(--danger-line); border-radius: 10px; background: var(--danger-bg); }
.msg.info { color: var(--fog); }
.alt { margin: 0; text-align: center; color: var(--fog); font-size: 0.95rem; }
.alt a { color: var(--paper); font-weight: 650; }
.demo { margin-top: 2px; }

footer { padding: 20px 16px 28px; text-align: center; color: var(--fog); font-size: 0.85rem; }
footer a { color: var(--fog); }
footer a:hover { color: var(--paper); }

@media (prefers-reduced-motion: reduce) { * { transition: none !important; animation: none !important; } }

.theme-btn { display: inline-flex; align-items: center; justify-content: center; width: 40px; height: 40px; padding: 0; border-radius: 10px; border: 1px solid transparent; background: transparent; color: var(--fog); cursor: pointer; transition: border-color .15s, color .15s; }
.theme-btn:hover { border-color: var(--line-strong); color: var(--paper); }
.theme-btn svg { width: 20px; height: 20px; }