:root {
  color-scheme: light;
  --charcoal: #1C1917;
  --charcoal-hover: #0C0A09;
  --btn-bg: #1C1917;
  --btn-ink: #FFFFFF;
  --btn-hover: #0C0A09;
  --grid-line: rgba(28,25,23,0.04);
  --accent: #2563EB;
  --bg: #FAFAFA;
  --surface: #FFFFFF;
  --border: #E7E5E4;
  --text: #1C1917;
  --text-secondary: #57534E;
  --text-muted: #78716C;
  --error: #DC2626;
  --error-bg: rgba(220, 38, 38, 0.08);
  --hover-surface: #F5F5F4;
  --focus-ring: rgba(28, 25, 23, 0.09);
  --radius: 4px;
  --radius-md: 6px;
  --shadow-sm: 0 1px 2px rgba(28, 25, 23, 0.04);
  --shadow-md: 0 4px 12px rgba(28, 25, 23, 0.08);
  --shadow-lg: 0 8px 24px rgba(28, 25, 23, 0.12);
  --font-display: "Space Grotesk", Inter, system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-body: Inter, system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 48px 16px;
  background: var(--bg);
  background-image: linear-gradient(var(--grid-line) 1px, transparent 1px), linear-gradient(90deg, var(--grid-line) 1px, transparent 1px);
  background-size: 32px 32px;
  color: var(--text);
  font: 400 16px/1.6 var(--font-body);
}
main {
  width: min(440px, 100%);
  padding: 32px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow-md);
}
.brand-row { display: flex; align-items: center; gap: 12px; margin-bottom: 24px; }
.brand-mark { display: grid; width: 36px; height: 36px; place-items: center; border-radius: var(--radius); background: var(--btn-bg); color: var(--btn-ink); font-family: var(--font-display); font-weight: 700; font-size: 18px; overflow: hidden; }
.brand-mark img { width: 100%; height: 100%; object-fit: cover; display: block; }
.brand-name { font-family: var(--font-display); font-size: 16px; font-weight: 600; line-height: 1.35; }
.brand-name small { display: block; font-family: var(--font-body); font-size: 12px; font-weight: 500; letter-spacing: 0.5px; text-transform: uppercase; color: var(--text-secondary); }
h1 { margin: 0 0 8px; font-family: var(--font-display); font-size: 32px; font-weight: 700; line-height: 1.2; letter-spacing: -0.01em; }
p { color: var(--text-secondary); margin: 0 0 24px; font-size: 16px; }
label { display: block; margin: 0 0 6px; color: var(--text); font-size: 14px; font-weight: 500; }
input {
  width: 100%; height: 40px; padding: 8px 12px;
  border: 1px solid var(--border); border-radius: var(--radius);
  outline: 0; color: var(--text); background: var(--surface); font: inherit; font-size: 14px;
}
input + label { margin-top: 16px; }
input:hover { border-color: var(--text); }
input:focus { border: 2px solid var(--text); padding: 7px 11px; box-shadow: 0 0 0 3px var(--focus-ring); }
button {
  width: 100%; height: 40px; margin-top: 16px; padding: 8px 20px;
  border: 0; border-radius: var(--radius);
  color: var(--btn-ink); background: var(--btn-bg);
  font-size: 14px; font-weight: 500;
  box-shadow: var(--shadow-sm); cursor: pointer;
}
button:hover { background: var(--btn-hover); }
button:active { transform: scale(0.98); }
button:disabled { opacity: 0.4; cursor: not-allowed; }
.theme-toggle { margin-top: 8px; border: 1px solid var(--border); color: var(--text-secondary); background: transparent; box-shadow: none; }
.theme-toggle:hover { color: var(--text); background: var(--hover-surface); }
.error {
  margin: 0 0 16px; padding: 8px 12px;
  border-radius: var(--radius);
  color: var(--error); background: var(--error-bg);
  font-size: 14px;
}
.helper { margin: 16px 0 0; font-size: 12px; color: var(--text-muted); text-align: center; }
.helper code { font-family: var(--font-mono); font-size: 12px; background: var(--hover-surface); padding: 2px 6px; border-radius: 2px; }

/* Dark mode: explicit override wins; media query covers no-preference first paint */
html[data-theme="dark"] {
  color-scheme: dark;
  --bg: #0C0A09;
  --surface: #1C1917;
  --border: #44403C;
  --text: #FAFAFA;
  --text-secondary: #D6D3D1;
  --text-muted: #A8A29E;
  --btn-bg: #FAFAFA;
  --btn-ink: #1C1917;
  --btn-hover: #E7E5E4;
  --grid-line: rgba(255,255,255,0.06);
  --error-bg: rgba(220, 38, 38, 0.16);
  --hover-surface: #292524;
  --focus-ring: rgba(255, 255, 255, 0.18);
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.45);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.5);
}
@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --bg: #0C0A09;
    --surface: #1C1917;
    --border: #44403C;
    --text: #FAFAFA;
    --text-secondary: #D6D3D1;
    --text-muted: #A8A29E;
    --btn-bg: #FAFAFA;
    --btn-ink: #1C1917;
    --btn-hover: #E7E5E4;
    --grid-line: rgba(255,255,255,0.06);
    --error-bg: rgba(220, 38, 38, 0.16);
    --hover-surface: #292524;
    --focus-ring: rgba(255, 255, 255, 0.18);
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.45);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.5);
  }
}
html[data-theme="light"] {
  color-scheme: light;
  --bg: #FAFAFA;
  --surface: #FFFFFF;
  --border: #E7E5E4;
  --text: #1C1917;
  --text-secondary: #57534E;
  --text-muted: #78716C;
  --btn-bg: #1C1917;
  --btn-ink: #FFFFFF;
  --btn-hover: #0C0A09;
  --grid-line: rgba(28,25,23,0.04);
  --hover-surface: #F5F5F4;
  --focus-ring: rgba(28, 25, 23, 0.09);
}