* { box-sizing: border-box; }
body { margin: 0; font-family: system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif; line-height: 1.4; background: #fcfcfc; }
a { color: inherit; text-decoration: none; }
.container { max-width: 980px; margin: 0 auto; padding: 16px; }

.header { border-bottom: 1px solid #eaeaea; background: #fff; position: sticky; top: 0; }
.header__inner { display: flex; align-items: center; justify-content: space-between; gap: 12px; }
.logo { font-weight: 700; }
.nav a { margin-left: 12px; color: #444; }
.nav a:hover { text-decoration: underline; }

.footer { border-top: 1px solid #eaeaea; margin-top: 32px; padding: 16px 0; color: #777; }

.muted { color: #666; }


/* ===== Page header (title + filter) ===== */
.page-head { display: flex; align-items: flex-end; justify-content: space-between; gap: 16px; flex-wrap: wrap; margin: 8px 0 10px; }
.page-title { margin: 0; font-size: 40px; letter-spacing: -0.5px; }
.page-subtitle { margin: 8px 0 0; max-width: 680px; }
.btn-link { color: #444; text-decoration: underline; font-size: 14px; }

/* ===== Lectures cards ===== */
.lecture-card__title { display: flex; align-items: center; gap: 10px; }
.lecture-card__icon { font-size: 20px; line-height: 1; }
.lecture-card__cta { margin-top: 10px; font-size: 13px; }

.filter { margin: 12px 0 16px; display: flex; gap: 10px; align-items: center; flex-wrap: wrap; }
.filter select { padding: 8px 10px; border-radius: 10px; border: 1px solid #ddd; background: #fff; }

.task-list { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 12px; margin-top: 16px; }
.task-card { border: 1px solid #eaeaea; border-radius: 10px; padding: 14px; background: #fff; }
.task-card:hover { border-color: #d0d0d0; }
.task-card__top { display: flex; align-items: start; justify-content: space-between; gap: 10px; }
.task-card__title { margin: 0; font-size: 18px; }
.task-card__desc { margin: 10px 0 0; color: #555; }

.badge { display: inline-block; padding: 2px 8px; border-radius: 999px; border: 1px solid #ddd; font-size: 12px; color: #444; white-space: nowrap; }

.task-header { display: flex; align-items: center; justify-content: space-between; gap: 12px; }

.code { background: #0b1020; color: #e9eefc; padding: 12px; border-radius: 10px; overflow: auto; }

.sql-form textarea { width: 100%; font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; padding: 10px; border-radius: 10px; border: 1px solid #ddd; }
.form-actions { display: flex; gap: 10px; margin-top: 10px; flex-wrap: wrap; }

button { padding: 9px 12px; border: 1px solid #ccc; border-radius: 10px; background: #111; color: #fff; cursor: pointer; }
button.secondary { background: #fff; color: #111; }
button:hover { opacity: 0.92; }

.alert { padding: 10px 12px; border-radius: 10px; background: #fff3f3; border: 1px solid #ffd0d0; color: #8a1f1f; }

.table-wrap { overflow: auto; border: 1px solid #eaeaea; border-radius: 10px; background: #fff; }
table { width: 100%; border-collapse: collapse; }
th, td { padding: 10px; border-bottom: 1px solid #f0f0f0; text-align: left; font-size: 14px; }
thead th { background: #fafafa; }

.flash-list { margin: 10px 0; display: grid; gap: 8px; }
.flash { padding: 10px 12px; border-radius: 10px; border: 1px solid #ddd; background: #f7f7f7; }
.flash--info { border-color: #cfe6ff; background: #eef6ff; }
.flash--ok { border-color: #c9f2d2; background: #eefbf1; }
.flash--bad { border-color: #ffd0d0; background: #fff3f3; }
/* ===== SQL code blocks ===== */
/* ===== SQL code blocks (neutral) ===== */
pre.sql {
  background: #f6f8fa;         /* мягкий светло-серый */
  color: #1f2328;
  padding: 12px 14px;
  border-radius: 10px;
  overflow-x: auto;
  font-size: 14px;
  line-height: 1.55;
  margin: 14px 0;
  border: 1px solid #e5e7eb;
}

pre.sql code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  white-space: pre;
}
/* ===== Example result table for lectures ===== */
.result {
  margin: 10px 0 18px;
}

.result__title {
  font-size: 13px;
  color: #6b7280;
  margin: 8px 0 6px;
}

.result table {
  width: 100%;
  border-collapse: collapse;
  background: #fff;
  border: 1px solid #e5e7eb;
  border-radius: 10px;
  overflow: hidden; /* чтобы скругление работало */
}

.result th, .result td {
  padding: 10px 12px;
  border-bottom: 1px solid #f0f0f0;
  text-align: left;
  font-size: 14px;
}

.result thead th {
  background: #f9fafb;
  color: #374151;
}

/* ===== Lectures typography ===== */
.lecture {
  max-width: 900px;
}

.lecture h1 {
  margin: 8px 0 10px;
  font-size: 40px;
  letter-spacing: -0.5px;
}

.lecture h2 {
  margin: 26px 0 10px;
  font-size: 22px;
}

.lecture h3 {
  margin: 18px 0 8px;
  font-size: 16px;
  color: #333;
}

.lecture p {
  font-size: 15px;
  line-height: 1.65;
  color: #222;
  margin: 10px 0;
}

.lecture ul {
  margin: 10px 0 10px 20px;
}

.lecture li {
  margin: 6px 0;
}

.lecture hr {
  border: 0;
  border-top: 1px solid #eee;
  margin: 22px 0;
}

.lecture code {
  background: #f3f4f6;
  border: 1px solid #e5e7eb;
  padding: 1px 6px;
  border-radius: 8px;
  font-size: 0.95em;
}

/* Neutral SQL block */
pre.sql {
  background: #f6f8fa;
  color: #1f2328;
  padding: 12px 14px;
  border-radius: 10px;
  overflow-x: auto;
  font-size: 14px;
  line-height: 1.55;
  margin: 14px 0;
  border: 1px solid #e5e7eb;
}

pre.sql code {
  background: transparent;
  border: 0;
  padding: 0;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  white-space: pre;
}

/* ===== Lecture callouts: note / tip / warning ===== */
.callout {
  border: 1px solid #e5e7eb;
  background: #fff;
  border-radius: 12px;
  padding: 12px 14px;
  margin: 12px 0;
}

.callout__title {
  font-weight: 700;
  margin-bottom: 6px;
}

.callout--warning {
  border-color: #ffd0d0;
  background: #fff3f3;
  color: #7a1f1f;
}

.callout--tip {
  border-color: #cfe6ff;
  background: #eef6ff;
  color: #123b6b;
}

.callout--note {
  border-color: #e5e7eb;
  background: #f9fafb;
  color: #374151;
}

/* "Mistakes" list inside callout */
.mistakes {
  margin: 8px 0 0 18px;
}

.mistakes li {
  margin: 8px 0;
}

.mistakes code {
  background: rgba(255,255,255,0.35);
  border-color: rgba(0,0,0,0.08);
}