:root {
  --navy: #16215c;
  --navy-deep: #0c1338;
  --blue: #2f86c9;
  --sky: #6fcbea;
  --sky-light: #eaf7fc;
  --bg: #f3f6fb;
  --card-bg: #ffffff;
  --text: #17203f;
  --muted: #6b7488;
  --border: #e3e8f2;
  --danger: #dc2626;
  --radius: 14px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: Tahoma, "Vazirmatn", system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
}

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: linear-gradient(135deg, var(--navy) 0%, var(--navy-deep) 100%);
  padding: 14px 24px;
  flex-wrap: wrap;
  gap: 10px;
  box-shadow: 0 2px 12px rgba(12, 19, 56, 0.25);
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: bold;
  font-size: 1.25rem;
  color: #fff;
  text-decoration: none;
}

.brand img { height: 38px; width: auto; display: block; }

.topbar nav { display: flex; gap: 20px; align-items: center; flex-wrap: wrap; }
.topbar nav a { color: #d9e6f7; text-decoration: none; font-size: 0.95rem; }
.topbar nav a:hover { color: var(--sky); }
.topbar nav .link-button { color: #d9e6f7; }
.topbar nav .link-button:hover { color: var(--sky); }

.container {
  max-width: 640px;
  margin: 0 auto;
  padding: 24px 16px 60px;
}

.card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px;
  margin-bottom: 16px;
  box-shadow: 0 2px 10px rgba(22, 33, 92, 0.05);
}

.card.narrow { max-width: 480px; margin-left: auto; margin-right: auto; }

.grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-bottom: 16px;
}

.link-card { text-decoration: none; color: inherit; display: block; transition: transform .15s, box-shadow .15s; }
.link-card:hover { border-color: var(--sky); transform: translateY(-2px); box-shadow: 0 6px 16px rgba(22, 33, 92, 0.1); }
.link-card h2 { margin: 0 0 6px; font-size: 1rem; color: var(--navy); }
.link-card p { margin: 0; color: var(--muted); font-size: 0.85rem; }

h1 { font-size: 1.35rem; margin-top: 0; color: var(--navy); }
h2 { font-size: 1.05rem; color: var(--navy); }

form label {
  display: block;
  margin-bottom: 14px;
  font-size: 0.9rem;
  color: var(--muted);
}

input, textarea {
  width: 100%;
  margin-top: 6px;
  padding: 11px 14px;
  border: 1px solid var(--border);
  border-radius: 9px;
  font-family: inherit;
  font-size: 1rem;
  background: #fff;
  color: var(--text);
  transition: border-color .15s, box-shadow .15s;
}
input:focus, textarea:focus {
  outline: none;
  border-color: var(--sky);
  box-shadow: 0 0 0 3px rgba(111, 203, 234, 0.25);
}

button {
  font-family: inherit;
  font-size: 1rem;
  cursor: pointer;
}

.primary, .button-link {
  display: inline-block;
  background: linear-gradient(135deg, var(--blue) 0%, var(--navy) 100%);
  color: #fff;
  border: none;
  border-radius: 9px;
  padding: 11px 22px;
  text-decoration: none;
  text-align: center;
  font-weight: bold;
  box-shadow: 0 3px 10px rgba(47, 134, 201, 0.3);
}
.primary:hover, .button-link:hover { filter: brightness(1.08); }

.danger {
  background: none;
  border: 1px solid var(--danger);
  color: var(--danger);
  border-radius: 9px;
  padding: 8px 16px;
}

.link-button {
  background: none;
  border: none;
  color: var(--muted);
  text-decoration: underline;
  padding: 0;
}

.inline-form { display: inline; }

.flash-box {
  background: var(--sky-light);
  border: 1px solid var(--sky);
  border-radius: var(--radius);
  padding: 12px 18px;
  margin-bottom: 16px;
  color: var(--navy);
}
.flash-box p { margin: 4px 0; }

.deck-row {
  display: flex;
  justify-content: space-between;
  padding: 12px 0;
  border-top: 1px solid var(--border);
  text-decoration: none;
  color: var(--text);
}
.deck-row:first-of-type { border-top: none; }
.deck-row:hover span:first-child { color: var(--blue); }
.deck-meta { color: var(--muted); font-size: 0.85rem; }

.review-progress { color: var(--muted); font-size: 0.85rem; }
.review-answer { font-size: 1.1rem; background: var(--sky-light); padding: 14px; border-radius: 10px; color: var(--navy); }

.rating-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-top: 16px;
}
.rating {
  border: none;
  border-radius: 9px;
  padding: 14px;
  color: #fff;
  font-size: 0.95rem;
  font-weight: bold;
}
.rating-again { background: #ef4444; }
.rating-hard { background: #f59e0b; }
.rating-good { background: #22c55e; }
.rating-easy { background: var(--blue); }

/* --- login page --- */
.login-wrap {
  min-height: calc(100vh - 70px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
}
.login-card {
  background: var(--card-bg);
  border-radius: 18px;
  box-shadow: 0 10px 40px rgba(22, 33, 92, 0.12);
  padding: 32px 28px;
  width: 100%;
  max-width: 380px;
  text-align: center;
}
.login-card img.login-logo { width: 200px; margin-bottom: 22px; }
.login-card form { text-align: right; }
.login-card .primary { width: 100%; margin-top: 8px; }