/* Modern, responsive layout with dark mode and centered content */
:root {
  --bg: #f5f7fb;
  --text: #0f172a;
  --muted: #475569;
  --card-bg: #ffffff;
  --border: #e2e8f0;
  --accent: #2563eb;
  --accent-contrast: #ffffff;
  --danger: #dc2626;
  --danger-hover: #b91c1c;
  --ok-bg: #e6ffed;
  --ok-border: #b7f5c6;
  --ok-text: #055b16;
  --err-bg: #ffecec;
  --err-border: #f5b7b7;
  --err-text: #7a0b0b;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b1220;
    --text: #e5e7eb;
    --muted: #9aa3b2;
    --card-bg: #121826;
    --border: #1f2937;
    --accent: #3b82f6;
    --accent-contrast: #ffffff;
    --danger: #ef4444;
    --danger-hover: #dc2626;
    --ok-bg: #0f3f1a;
    --ok-border: #176836;
    --ok-text: #86efac;
    --err-bg: #3a0a0a;
    --err-border: #7f1d1d;
    --err-text: #fecaca;
  }
}

html, body { height: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  display: grid;
  place-items: center;
  min-height: 100vh;
}

.card {
  width: min(calc(100% - 2rem), 560px);
  box-sizing: border-box;
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 1.25rem 1.5rem;
  box-shadow: 0 10px 25px rgba(0,0,0,0.08);
}

.topbar { display: flex; justify-content: flex-end; align-items: center; margin-bottom: .5rem; }
.logout-btn { background: var(--danger); color: var(--accent-contrast); border-radius: 10px; padding: 0; display: inline-flex; align-items: center; justify-content: center; width: 36px; height: 36px; }
.logout-btn:hover { background: var(--danger-hover); }
.logout-btn img, .logout-btn svg { width: 20px; height: 20px; display: block; }

h1 { margin: 0 0 .75rem; font-size: 1.35rem; }
.help { color: var(--muted); margin: 0 0 1rem; }

label { font-weight: 600; display: block; margin-bottom: .5rem; }
input[type=file], input[type=password], input[type=text], select { display: block; width: 100%; box-sizing: border-box; border: 1px solid var(--border); background: var(--card-bg); color: var(--text); border-radius: 10px; padding: .6rem .8rem; font-size: 1rem; }
select { appearance: none; background-image: linear-gradient(45deg, transparent 50%, var(--muted) 50%), linear-gradient(135deg, var(--muted) 50%, transparent 50%); background-position: calc(100% - 14px) calc(1rem - 2px), calc(100% - 9px) calc(1rem - 2px); background-size: 5px 5px, 5px 5px; background-repeat: no-repeat; }
input[type=file] { padding: .4rem; }
input:focus, select:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px rgba(37,99,235,0.25); }

.actions { margin-top: .9rem; display: flex; justify-content: center; }
button {
  appearance: none; border: none; cursor: pointer;
  padding: .65rem 1rem; border-radius: 10px;
  background: var(--accent); color: var(--accent-contrast);
  font-size: 1rem; font-weight: 600; letter-spacing: .2px;
}
button:hover { filter: brightness(1.05); }
button:active { transform: translateY(1px); }

.result { margin-top: 1rem; padding: .85rem; border-radius: 10px; white-space: pre-wrap; }
.result.ok { background: var(--ok-bg); border: 1px solid var(--ok-border); color: var(--ok-text); }
.result.err { background: var(--err-bg); border: 1px solid var(--err-border); color: var(--err-text); }

footer { margin-top: 1rem; color: var(--muted); font-size: .95rem; text-align: center; }
.footer-meta { margin-top: .5rem; color: var(--muted); font-size: .9rem; }