/* ─── Variables & Reset ─────────────────────────────────────────────────── */

:root {
  --bg: #f0f2f5;
  --text: #1c1e21;
  --muted: #65676b;
  --card: #ffffff;
  --primary: #1877f2;
  --primary-hover: #166fe0;
  --success: #42b72a;
  --success-hover: #36a420;
  --border: #dddfe2;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #18191a;
    --text: #e4e6eb;
    --muted: #b0b3b8;
    --card: #242526;
    --primary: #4599ff;
    --primary-hover: #3182f6;
    --success: #45bd62;
    --success-hover: #36a420;
    --border: #3a3b3c;
  }
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 14px/1.4 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

/* ─── index.html ────────────────────────────────────────────────────────── */

/* 4 explicit rows: banner | disclaimer | main (grows) | footer */
.index-body {
  display: grid;
  grid-template-rows: auto auto 1fr auto;
  min-height: 100vh;
}

.demo-banner {
  background: #1877f2;
  color: #fff;
  padding: 36px 30px;
  text-align: center;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.2px;
}

.edu-disclaimer {
  background: #fff3cd;
  color: #856404;
  border: 1px solid #ffe8a1;
  padding: 4px 8px;
  margin: 8px auto;
  max-width: 980px;
  border-radius: 4px;
  font-size: 12px;
  line-height: 1.2;
  text-align: center;
}

.container {
  width: 100%;
  max-width: 980px;
  padding: 40px 16px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 40px;
  align-items: start;
}

@media (max-width: 900px) {
  .container { grid-template-columns: 1fr; gap: 24px; }
}

.brand { display: flex; flex-direction: column; gap: 12px; }
.brand .logo {
  color: #1877f2;
  font-size: 48px;
  font-weight: 700;
  letter-spacing: -0.5px;
}
.brand .tagline { font-size: 28px; line-height: 1.2; }

@media (max-width: 900px) {
  .brand { align-items: center; text-align: center; }
  .brand .logo { font-size: 42px; }
  .brand .tagline { font-size: 24px; }
}

.card {
  background: var(--card);
  border-radius: 8px;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
  padding: 16px;
}

form { display: grid; gap: 12px; }
label { font-weight: 600; font-size: 13px; }
.input {
  width: 100%;
  padding: 14px 12px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: transparent;
  color: var(--text);
  font: inherit;
}

.password-wrapper { position: relative; }
.input-password { padding-right: 44px; }

.toggle-password {
  position: absolute;
  right: 10px;
  top: 50%;
  transform: translateY(-50%);
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
  color: var(--muted);
}

#icon-eye-off { display: none; }

.actions { display: flex; flex-direction: column; gap: 12px; }
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 16px;
  border: 0;
  border-radius: 6px;
  cursor: pointer;
  font-weight: 700;
  font-size: 14px;
  font-family: inherit;
}
.btn-primary { background: var(--primary); color: #ffffff; }
.btn-primary:hover { background: var(--primary-hover); }
.btn-secondary { background: var(--success); color: #ffffff; }
.btn-secondary:hover { background: var(--success-hover); }

.link { color: var(--primary); text-decoration: none; font-weight: 600; text-align: center; }
.link:hover { text-decoration: underline; }
.divider { height: 1px; background: var(--border); margin: 8px 0; }
.note { font-size: 12px; color: var(--muted); text-align: center; }

footer { width: 100%; max-width: 980px; margin: 0 auto 24px; padding: 0 16px; color: var(--muted); font-size: 12px; }
footer ul { list-style: none; padding: 0; margin: 8px 0 0; display: flex; flex-wrap: wrap; gap: 12px; }
footer a { color: inherit; text-decoration: none; }
footer a:hover { text-decoration: underline; }

/* ─── loading.html ──────────────────────────────────────────────────────── */

.loading-body {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
}

.loading-container {
  text-align: center;
  max-width: 400px;
  padding: 40px 20px;
}

.loading-logo {
  color: var(--primary);
  font-size: 48px;
  font-weight: 700;
  letter-spacing: -0.5px;
  margin-bottom: 20px;
}

.loading-title {
  font-size: 24px;
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--text);
}

.loading-subtitle {
  font-size: 16px;
  color: var(--muted);
  margin-bottom: 40px;
  line-height: 1.4;
}

.spinner {
  width: 60px;
  height: 60px;
  border: 4px solid var(--border);
  border-top: 4px solid var(--primary);
  border-radius: 50%;
  animation: spin 1s linear infinite;
  margin: 0 auto 30px;
}

@keyframes spin {
  0%   { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

.status-text {
  font-size: 14px;
  color: var(--muted);
  margin-bottom: 20px;
}

.security-note {
  font-size: 12px;
  color: var(--muted);
  margin-top: 24px;
  margin-bottom: 0;
  max-width: 320px;
  margin-left: auto;
  margin-right: auto;
  line-height: 1.5;
}

.back-button {
  display: inline-block;
  margin-top: 30px;
  padding: 12px 24px;
  background: var(--primary);
  color: white;
  text-decoration: none;
  border-radius: 6px;
  font-weight: 600;
  font-family: inherit;
  transition: background 0.2s;
}

.back-button:hover { background: var(--primary-hover); }