/* ============================================================
   ПЕРЕМЕННЫЕ И БАЗОВЫЕ СТИЛИ
   ============================================================ */
* { box-sizing: border-box; }

:root {
  --color-primary: #3f51b5;
  --color-primary-dark: #2c387e;
  --color-accent: #ff8a00;
  --color-bg: #eef1f7;
  --color-surface: #ffffff;
  --color-text: #222;
  --color-muted: #555;
  --radius: 12px;
  --shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
  --shadow-hover: 0 8px 20px rgba(0, 0, 0, 0.12);
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 100px;
}

body {
  margin: 0;
  padding: 80px 20px 20px;
  font-family: "Segoe UI", "Arial", "Helvetica", sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-text);
  background: var(--color-bg);
}

/* ============================================================
   ШАПКА
   ============================================================ */
header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 14px 20px;
  background: linear-gradient(135deg, #3f51b5, #5c6bc0);
  color: #fff;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.15);
  text-align: center;
}

header h1 {
  margin: 0;
  font-size: 22px;
  letter-spacing: 0.5px;
}

header p {
  margin: 4px 0 0;
  font-size: 14px;
  opacity: 0.9;
}

/* ============================================================
   НАВИГАЦИЯ
   ============================================================ */
nav {
  position: sticky;
  top: 68px;
  z-index: 90;
  margin: 0 -20px 24px;
  padding: 10px 20px;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid #dde2ee;
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.04);
}

nav ul {
  display: flex;
  flex-wrap: nowrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

nav li { flex: 0 0 auto; }

nav a {
  display: inline-block;
  padding: 8px 16px;
  border-radius: 20px;
  font-size: 14px;
  font-weight: 600;
  color: var(--color-primary);
  text-decoration: none;
  white-space: nowrap;
  transition: background 0.2s, color 0.2s, transform 0.15s;
}

nav a:hover {
  background: var(--color-primary);
  color: #fff;
  transform: translateY(-1px);
}

/* ============================================================
   СЕКЦИИ
   ============================================================ */
section {
  max-width: 900px;
  margin: 0 auto 24px;
  padding: 28px;
  background: var(--color-surface);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  transition: box-shadow 0.25s;
}

section:hover { box-shadow: var(--shadow-hover); }

h2 {
  margin: 0 0 16px;
  padding-bottom: 8px;
  font-size: 24px;
  color: var(--color-primary);
  border-bottom: 3px solid var(--color-primary);
}

h3 {
  margin: 24px 0 10px;
  font-size: 18px;
  color: var(--color-muted);
}

p { margin: 0 0 12px; }

/* ============================================================
   ФОТО
   ============================================================ */
#about img {
  float: left;
  width: 180px;
  height: auto;
  margin: 0 20px 12px 0;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  transition: transform 0.3s;
}

#about img:hover { transform: scale(1.03); }

/* ============================================================
   СПИСКИ
   ============================================================ */
ul, ol {
  padding-left: 22px;
  margin: 0 0 12px;
}

li { margin-bottom: 4px; }
li::marker { color: var(--color-primary); }

/* ============================================================
   ОБЫЧНЫЕ ТАБЛИЦЫ (2.1)
   ============================================================ */
table {
  width: 100%;
  margin: 12px 0 20px;
  border-collapse: collapse;
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
}

caption {
  margin-bottom: 8px;
  font-weight: 700;
  color: var(--color-primary);
  text-align: left;
}

th {
  padding: 10px 12px;
  background: var(--color-primary);
  color: #fff;
  text-align: left;
  font-weight: 600;
}

td {
  padding: 10px 12px;
  border-bottom: 1px solid #e5e8f0;
}

tbody tr:nth-child(even) { background: #f5f7fb; }
tbody tr:hover { background: #eef1fb; }

/* ============================================================
   ССЫЛКИ
   ============================================================ */
a {
  color: #0066cc;
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.2s, border-color 0.2s;
}

a:hover {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
}

/* ============================================================
   ЦИТАТА
   ============================================================ */
blockquote {
  margin: 16px 0 0;
  padding: 12px 18px;
  background: #f5f7fb;
  border-left: 4px solid var(--color-primary);
  border-radius: 0 var(--radius) var(--radius) 0;
  font-style: italic;
  color: var(--color-muted);
}

blockquote cite {
  display: block;
  margin-top: 6px;
  font-style: normal;
  font-size: 14px;
  color: #888;
}

/* ============================================================
   DETAILS
   ============================================================ */
details {
  margin: 12px 0 20px;
  padding: 12px 16px;
  background: #f5f7fb;
  border-radius: var(--radius);
  border-left: 4px solid var(--color-accent);
}

summary {
  cursor: pointer;
  font-weight: 600;
  color: var(--color-primary);
  outline: none;
}

summary:hover { color: var(--color-accent); }
details[open] summary { margin-bottom: 8px; }

/* ============================================================
   PROGRESS
   ============================================================ */
progress {
  appearance: none;
  width: 220px;
  height: 12px;
  margin-left: 8px;
  border: none;
  border-radius: 6px;
  background: #e5e8f0;
  vertical-align: middle;
  overflow: hidden;
}

progress::-webkit-progress-bar { background: #e5e8f0; border-radius: 6px; }
progress::-webkit-progress-value { background: linear-gradient(90deg, #3f51b5, #5c6bc0); border-radius: 6px; }
progress::-moz-progress-bar { background: linear-gradient(90deg, #3f51b5, #5c6bc0); border-radius: 6px; }

/* ============================================================
   ADDRESS
   ============================================================ */
address {
  margin-top: 12px;
  padding: 10px 14px;
  background: #f5f7fb;
  border-radius: var(--radius);
  font-style: normal;
  color: var(--color-muted);
}

/* ============================================================
   ПОДВАЛ
   ============================================================ */
footer {
  max-width: 900px;
  margin: 0 auto;
  padding: 20px;
  background: #2c387e;
  color: #cfd6f5;
  text-align: center;
  border-radius: var(--radius);
  font-size: 14px;
}

footer p { margin: 4px 0; }

/* ============================================================
   ТАБЛИЦА А (задание 2.2)
   ============================================================ */
.table-a {
  width: 720px;
  border-collapse: collapse;
  border-spacing: 0;
  table-layout: fixed;
  margin: 12px 0 24px;
  border-radius: 0;
  box-shadow: none;
  overflow: visible;
}

.table-a,
.table-a td,
.table-a th {
  border: 2px solid #000;
}

.table-a td {
  padding: 3px;
  width: 112px;
  height: 40px;
  background: #fff;
}

/* ============================================================
   ТАБЛИЦА Б (задание 2.2)
   ============================================================ */
.table-b {
  width: 480px;
  border-collapse: collapse;
  border-spacing: 0;
  table-layout: fixed;
  margin: 12px 0 24px;
  border-radius: 0;
  box-shadow: none;
  overflow: visible;
}

.table-b,
.table-b td,
.table-b th {
  border: 2px solid #000;
}

.table-b td {
  padding: 0;
  width: 60px;
  height: 60px;
}

.tg-6yod { background: #00e5c0; }
.tg-m9r4 { background: #fdf6c8; }
.tg-mnhx { background: #ff0000; }
.tg-8ytw { background: #0000ff; }
.tg-kd4e { background: #00ff00; }
.tg-s7ni { background: #ffff00; }

/* ============================================================
   ФОРМА А — Птицефабрика (задание 2.3)
   ============================================================ */
.form-poultry {
  max-width: 820px;
  border: 1px solid #ccc;
  padding: 20px 30px;
  margin-bottom: 30px;
  font-family: "Times New Roman", Times, serif;
  font-size: 16px;
}

.form-poultry .row {
  display: flex;
  align-items: center;
  margin-bottom: 8px;
}

.form-poultry .row > label {
  width: 220px;
  text-align: right;
  padding-right: 10px;
  flex-shrink: 0;
}

.form-poultry input[type="text"],
.form-poultry input[type="password"],
.form-poultry input[type="number"] {
  padding: 3px 5px;
  border: 1px solid #777;
  font-size: 15px;
  font-family: inherit;
}

.form-poultry #surname,
.form-poultry #initials,
.form-poultry #password { width: 280px; }

.form-poultry #address { width: 560px; }

.form-poultry #quantity { width: 90px; }

.form-poultry .type-group {
  display: flex;
  gap: 10px;
}

.form-poultry select {
  padding: 3px 5px;
  border: 1px solid #777;
  font-size: 15px;
  font-family: inherit;
  background: #fff;
}

.form-poultry .radio-group,
.form-poultry .checkbox-row {
  display: flex;
  align-items: center;
  gap: 6px;
}

.form-poultry .radio-group label,
.form-poultry .checkbox-row label {
  width: auto;
  text-align: left;
  padding-right: 15px;
}

.form-poultry input[type="radio"],
.form-poultry input[type="checkbox"] {
  margin: 0;
  cursor: pointer;
}

.form-poultry textarea {
  width: 560px;
  height: 60px;
  padding: 3px 5px;
  border: 1px solid #777;
  font-size: 15px;
  font-family: inherit;
  resize: vertical;
  vertical-align: top;
}

.form-poultry .buttons {
  margin-top: 20px;
  text-align: center;
}

.form-poultry button {
  padding: 8px 22px;
  font-size: 15px;
  font-family: inherit;
  border: none;
  border-radius: 4px;
  cursor: pointer;
  margin: 0 8px;
}

.form-poultry button[type="submit"] { background: #2c3e50; color: #fff; }
.form-poultry button[type="reset"] { background: #e74c3c; color: #fff; }
.form-poultry button:hover { opacity: 0.9; }

/* ============================================================
   ФОРМА Б — Регистрация сайта (задание 2.3)
   ============================================================ */
.form-register {
  max-width: 640px;
  font-family: "Times New Roman", Times, serif;
  font-size: 16px;
  margin-bottom: 30px;
}

.form-register label {
  display: block;
  margin-bottom: 3px;
}

.form-register input[type="text"],
.form-register input[type="password"],
.form-register input[type="url"],
.form-register input[type="file"] {
  width: 180px;
  padding: 3px 5px;
  border: 1px solid #777;
  font-size: 15px;
  font-family: inherit;
  margin-bottom: 10px;
}

.form-register textarea {
  width: 520px;
  height: 180px;
  padding: 4px 6px;
  border: 1px solid #3a5fa0;
  font-size: 15px;
  font-family: inherit;
  margin-bottom: 10px;
  resize: vertical;
  display: block;
}

.form-register select {
  width: 180px;
  padding: 3px 5px;
  border: 1px solid #777;
  font-size: 15px;
  font-family: inherit;
  margin-bottom: 10px;
}

.form-register .file-row {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 15px;
}

.form-register .file-row input[type="file"] {
  margin-bottom: 0;
  width: auto;
}

.form-register .file-name {
  font-size: 15px;
  color: #333;
}

.form-register .buttons {
  display: flex;
  gap: 10px;
  margin-top: 5px;
}

.form-register button {
  padding: 4px 12px;
  font-size: 15px;
  font-family: inherit;
  font-weight: bold;
  border: 1px solid #555;
  background: linear-gradient(#f0f0f0, #d5d5d5);
  color: #000;
  cursor: pointer;
  border-radius: 3px;
}

.form-register button:hover { background: linear-gradient(#e5e5e5, #c5c5c5); }

/* ============================================================
   ЗАДАНИЕ 3 — таблицы в HTML
   ============================================================ */
.task3-content {
  font-family: "Times New Roman", Times, serif;
}

.mat {
  text-align: center;
  color: blue;
  font-family: "Monotype Corsiva", cursive;
  text-decoration: line-through;
  font-weight: bold;
}

.table-math {
  width: 100%;
  border: 1px solid black;
  border-collapse: collapse;
  margin-bottom: 20px;
  box-shadow: none;
  border-radius: 0;
}

.table-math td {
  width: 20%;
  border: 2px solid black;
  padding: 4px 6px;
}

.back-btn {
  display: inline-block;
  margin-top: 20px;
  padding: 8px 18px;
  background: var(--color-primary);
  color: #fff !important;
  border-radius: 20px;
  text-decoration: none;
  font-weight: 600;
  font-size: 14px;
  border: none;
  transition: background 0.2s, transform 0.15s;
}

.back-btn:hover {
  background: var(--color-primary-dark);
  border-bottom: none;
  transform: translateY(-1px);
}

/* ============================================================
   АДАПТИВ
   ============================================================ */
@media (max-width: 700px) {
  body { padding: 72px 12px 12px; }

  header h1 { font-size: 18px; }
  header p { font-size: 13px; }

  nav { top: 62px; margin: 0 -12px 16px; padding: 8px 12px; }

  section { padding: 18px; }
  h2 { font-size: 20px; }

  #about img {
    float: none;
    display: block;
    width: 140px;
    margin: 0 auto 16px;
  }

  progress { width: 140px; }

  .table-a, .table-b { width: 100%; }

  .form-poultry .row { flex-direction: column; align-items: flex-start; }
  .form-poultry .row > label {
    text-align: left;
    width: auto;
    padding-right: 0;
    margin-bottom: 4px;
  }
  .form-poultry #surname,
  .form-poultry #initials,
  .form-poultry #password,
  .form-poultry #address,
  .form-poultry textarea { width: 100%; }

  .form-register input[type="text"],
  .form-register input[type="password"],
  .form-register input[type="url"],
  .form-register textarea,
  .form-register select { width: 100%; }
}