/* ===== CSS Variables ===== */
:root {
  --color-primary: #6c5ce7;
  --color-primary-dark: #5a4bd1;
  --color-secondary: #fd79a8;
  --color-accent: #fdcb6e;
  --color-bg: #f8f9fa;
  --color-bg-alt: #ffffff;
  --color-text: #2d3436;
  --color-text-light: #636e72;
  --color-text-inverse: #ffffff;
  --color-border: #dfe6e9;
  --color-success: #00b894;
  --color-danger: #d63031;
  --color-warning: #f39c12;

  --font-primary: 'Roboto', 'Arial', sans-serif;
  --font-heading: 'Playfair Display', 'Georgia', serif;
  --font-playfair: 'Playfair Display', serif;
  --font-roboto: 'Roboto', sans-serif;
  --font-lobster: 'Lobster', cursive;
  --font-press: 'Press Start 2P', cursive;
  --font-caveat: 'Caveat', cursive;

  --header-height: 70px;
  --container-max: 1200px;
  --border-radius: 8px;
  --transition: 0.3s ease;
}

/* ===== Reset & Base ===== */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-height);
}

body {
  font-family: var(--font-primary);
  font-weight: 400;
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-bg);
  min-height: 100vh;
}

a {
  color: inherit;
  text-decoration: none;
}

ul {
  list-style: none;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

input {
  font-family: inherit;
}

/* ===== Utility ===== */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  white-space: nowrap;
  border: 0;
  clip: rect(0, 0, 0, 0);
}

.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 20px;
}

.section {
  padding: 80px 0;
}

.section__title {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 2.5rem;
  text-align: center;
  margin-bottom: 16px;
  color: var(--color-text);
}

.section__desc {
  text-align: center;
  font-size: 1.125rem;
  color: var(--color-text-light);
  margin-bottom: 48px;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

/* ===== HEADER ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  background-color: var(--color-bg-alt);
  border-bottom: 1px solid var(--color-border);
  z-index: 1000;
  transition: box-shadow var(--transition);
}

.header--scrolled {
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
}

.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.header__logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: 1.5rem;
  color: var(--color-primary);
  transition: opacity var(--transition);
}

.header__logo:hover {
  opacity: 0.8;
}

.header__logo-icon {
  font-size: 1.75rem;
}

.header__nav-list {
  display: flex;
  gap: 32px;
}

.header__nav-link {
  font-weight: 500;
  font-size: 0.9375rem;
  color: var(--color-text);
  transition: color var(--transition);
  position: relative;
}

.header__nav-link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--color-primary);
  transition: width var(--transition);
}

.header__nav-link:hover {
  color: var(--color-primary);
}

.header__nav-link:hover::after {
  width: 100%;
}

.header__burger {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 4px;
}

.header__burger-line {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--color-text);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

/* ===== HERO ===== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--color-primary) 0%, #a29bfe 50%, var(--color-secondary) 100%);
  padding-top: var(--header-height);
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: 'АБВГДЕЁЖЗИЙКЛМНОПРСТУФХЦЧШЩЪЫЬЭЮЯ';
  position: absolute;
  font-size: 14vw;
  font-weight: 900;
  color: rgba(255, 255, 255, 0.04);
  white-space: nowrap;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  pointer-events: none;
  letter-spacing: 0.05em;
  line-height: 1;
}

.hero__inner {
  position: relative;
  z-index: 1;
}

.hero__title {
  font-family: var(--font-heading);
  font-weight: 900;
  color: var(--color-text-inverse);
  margin-bottom: 24px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}

.hero__title-line {
  display: block;
  line-height: 1.1;
}

.hero__title-line--1 {
  font-size: 3rem;
  opacity: 0.8;
  letter-spacing: 0.3em;
}

.hero__title-line--2 {
  font-size: 5rem;
  letter-spacing: 0.15em;
}

.hero__title-line--3 {
  font-size: 7rem;
  color: var(--color-accent);
  text-shadow: 4px 4px 0 rgba(0, 0, 0, 0.1);
}

.hero__subtitle {
  font-size: 1.25rem;
  color: rgba(255, 255, 255, 0.9);
  max-width: 600px;
  margin: 0 auto 36px;
  line-height: 1.6;
}

.hero__btn {
  display: inline-block;
  padding: 16px 48px;
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--color-primary);
  background-color: var(--color-bg-alt);
  border-radius: 50px;
  transition: transform var(--transition), box-shadow var(--transition);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
}

.hero__btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(0, 0, 0, 0.2);
}

/* ===== ALPHABET ===== */
.alphabet {
  background-color: var(--color-bg-alt);
}

.alphabet__grid {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: 12px;
  max-width: 800px;
  margin: 0 auto;
}

.alphabet__letter {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  aspect-ratio: 1;
  font-size: 1.5rem;
  font-weight: 700;
  background-color: var(--color-bg);
  border: 2px solid var(--color-border);
  border-radius: var(--border-radius);
  cursor: pointer;
  transition: transform var(--transition), background-color var(--transition), color var(--transition), border-color var(--transition);
  user-select: none;
}

.alphabet__letter:hover {
  transform: scale(1.1);
  background-color: var(--color-primary);
  color: var(--color-text-inverse);
  border-color: var(--color-primary);
}

.alphabet__letter:active {
  transform: scale(1.05);
}

/* ===== FACTS (Слайдер) ===== */
.facts {
  background: linear-gradient(135deg, #dfe6e9 0%, #b2bec3 100%);
}

.facts__slider {
  display: flex;
  align-items: center;
  gap: 24px;
  max-width: 700px;
  margin: 0 auto 24px;
}

.facts__btn {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  background-color: var(--color-bg-alt);
  border-radius: 50%;
  transition: background-color var(--transition), color var(--transition);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
  color: var(--color-text);
}

.facts__btn:hover {
  background-color: var(--color-primary);
  color: var(--color-text-inverse);
}

.facts__slides {
  flex: 1;
  background-color: var(--color-bg-alt);
  border-radius: var(--border-radius);
  min-height: 160px;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
  position: relative;
  overflow: hidden;
}

.facts__slide {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  text-align: center;
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.5s ease, transform 0.5s ease;
  pointer-events: none;
  padding: 40px 32px;
}

.facts__slide--active {
  position: relative;
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.facts__slide-text {
  font-size: 1.25rem;
  line-height: 1.7;
  color: var(--color-text);
}

.facts__dots {
  display: flex;
  justify-content: center;
  gap: 10px;
}

.facts__dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background-color: var(--color-border);
  border: none;
  cursor: pointer;
  transition: background-color var(--transition), transform var(--transition);
}

.facts__dot:hover {
  transform: scale(1.3);
}

.facts__dot--active {
  background-color: var(--color-primary);
  transform: scale(1.2);
}

/* ===== TYPOGRAPHY ===== */
.typography {
  background-color: var(--color-bg-alt);
}

.typography__input-wrap {
  max-width: 500px;
  margin: 0 auto 48px;
}

.typography__input {
  width: 100%;
  padding: 16px 20px;
  font-size: 1.125rem;
  border: 2px solid var(--color-border);
  border-radius: var(--border-radius);
  outline: none;
  transition: border-color var(--transition);
  text-align: center;
}

.typography__input:focus {
  border-color: var(--color-primary);
}

.typography__demos {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 24px;
  max-width: 1000px;
  margin: 0 auto;
}

.typo-demo {
  background-color: var(--color-bg);
  border-radius: var(--border-radius);
  padding: 24px 16px;
  text-align: center;
  border: 1px solid var(--color-border);
  transition: transform var(--transition), box-shadow var(--transition);
}

.typo-demo:hover {
  transform: translateY(-4px);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.06);
}

.typo-demo__label {
  display: block;
  font-size: 0.8rem;
  color: var(--color-text-light);
  margin-bottom: 12px;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.typo-demo__text {
  font-size: 1.5rem;
  line-height: 1.4;
  word-break: break-word;
}

.typo-demo__text[data-font="playfair"] {
  font-family: var(--font-playfair);
}

.typo-demo__text[data-font="roboto"] {
  font-family: var(--font-roboto);
}

.typo-demo__text[data-font="lobster"] {
  font-family: var(--font-lobster);
  font-size: 1.75rem;
}

.typo-demo__text[data-font="press"] {
  font-family: var(--font-press);
  font-size: 0.875rem;
}

.typo-demo__text[data-font="caveat"] {
  font-family: var(--font-caveat);
  font-size: 2rem;
}

/* ===== Typography Controls & Preview ===== */
.typography__controls {
  display: flex;
  justify-content: center;
  gap: 32px;
  margin-bottom: 32px;
  flex-wrap: wrap;
  align-items: flex-end;
}

.typo-control {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.typo-control label {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--color-text-light);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.typo-control__select {
  padding: 10px 14px;
  font-size: 0.9375rem;
  border: 2px solid var(--color-border);
  border-radius: var(--border-radius);
  outline: none;
  background-color: var(--color-bg-alt);
  cursor: pointer;
  transition: border-color var(--transition);
  min-width: 160px;
}

.typo-control__select:focus {
  border-color: var(--color-primary);
}

.typo-colors {
  display: flex;
  gap: 8px;
}

.typo-color-btn {
  width: 34px;
  height: 34px;
  border-radius: 50%;
  border: 3px solid transparent;
  cursor: pointer;
  transition: transform var(--transition), border-color var(--transition);
}

.typo-color-btn:hover {
  transform: scale(1.15);
}

.typo-color-btn--active {
  border-color: var(--color-text);
  transform: scale(1.15);
}

.typography__preview {
  max-width: 600px;
  margin: 0 auto 40px;
  padding: 32px 24px;
  background-color: var(--color-bg);
  border-radius: var(--border-radius);
  border: 2px solid var(--color-border);
  text-align: center;
  min-height: 90px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.typo-preview__text {
  line-height: 1.3;
  word-break: break-word;
  transition: font-family var(--transition), font-size var(--transition), color var(--transition);
}

/* ===== Game Notification ===== */
.game__notification {
  max-width: 420px;
  margin: 0 auto 16px;
  padding: 12px 20px;
  border-radius: var(--border-radius);
  text-align: center;
  font-weight: 700;
  font-size: 1rem;
  opacity: 0;
  transform: translateY(-10px);
  transition: opacity 0.3s ease, transform 0.3s ease;
  min-height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.game__notification--visible {
  opacity: 1;
  transform: translateY(0);
}

.game__notification--correct {
  background-color: rgba(0, 184, 148, 0.15);
  color: var(--color-success);
  border: 1px solid rgba(0, 184, 148, 0.3);
}

.game__notification--wrong {
  background-color: rgba(214, 48, 49, 0.15);
  color: var(--color-danger);
  border: 1px solid rgba(214, 48, 49, 0.3);
}

.game__notification--timeout {
  background-color: rgba(243, 156, 18, 0.15);
  color: var(--color-warning);
  border: 1px solid rgba(243, 156, 18, 0.3);
}

/* ===== GAME ===== */
.game {
  background: linear-gradient(135deg, #dfe6e9 0%, #f5f6fa 100%);
}

.game__info {
  display: flex;
  justify-content: center;
  gap: 32px;
  margin-bottom: 32px;
  flex-wrap: wrap;
}

.game__score,
.game__timer,
.game__target {
  font-size: 1.125rem;
  font-weight: 700;
  padding: 12px 24px;
  background-color: var(--color-bg-alt);
  border-radius: var(--border-radius);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
}

.game__target span {
  color: var(--color-primary);
  font-size: 1.5rem;
}

.game__field {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 10px;
  max-width: 420px;
  margin: 0 auto 32px;
}

.game__field-letter {
  display: flex;
  align-items: center;
  justify-content: center;
  aspect-ratio: 1;
  font-size: 1.5rem;
  font-weight: 700;
  background-color: var(--color-bg-alt);
  border: 2px solid var(--color-border);
  border-radius: var(--border-radius);
  cursor: pointer;
  transition: transform var(--transition), background-color var(--transition);
  user-select: none;
}

.game__field-letter:hover {
  transform: scale(1.08);
}

.game__field-letter--correct {
  background-color: var(--color-success) !important;
  color: var(--color-text-inverse) !important;
  border-color: var(--color-success) !important;
}

.game__field-letter--wrong {
  background-color: var(--color-danger) !important;
  color: var(--color-text-inverse) !important;
  border-color: var(--color-danger) !important;
}

.game__field-letter--disabled {
  pointer-events: none;
  opacity: 0.6;
}

.game__btn {
  display: block;
  margin: 0 auto;
  padding: 14px 40px;
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--color-text-inverse);
  background-color: var(--color-primary);
  border-radius: 50px;
  transition: background-color var(--transition), transform var(--transition);
}

.game__btn:hover {
  background-color: var(--color-primary-dark);
  transform: translateY(-2px);
}

/* ===== FOOTER ===== */
.footer {
  background-color: var(--color-text);
  color: var(--color-text-inverse);
  padding: 40px 0;
}

.footer__inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 24px;
  flex-wrap: wrap;
}

.footer__copy {
  font-size: 0.9375rem;
  opacity: 0.8;
}

.footer__made {
  font-size: 0.875rem;
  opacity: 0.6;
  margin-top: 4px;
}

.footer__nav-list {
  display: flex;
  gap: 24px;
  flex-wrap: wrap;
}

.footer__nav-link {
  font-size: 0.875rem;
  opacity: 0.7;
  transition: opacity var(--transition);
}

.footer__nav-link:hover {
  opacity: 1;
}

/* ===== MODAL ===== */
.modal-overlay {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(0, 0, 0, 0.5);
  z-index: 2000;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.modal-overlay--open {
  display: flex;
}

.modal {
  background-color: var(--color-bg-alt);
  border-radius: 12px;
  padding: 40px 32px 32px;
  max-width: 480px;
  width: 100%;
  position: relative;
  animation: modalFadeIn 0.3s ease;
  max-height: 90vh;
  overflow-y: auto;
}

@keyframes modalFadeIn {
  from {
    opacity: 0;
    transform: scale(0.95) translateY(10px);
  }
  to {
    opacity: 1;
    transform: scale(1) translateY(0);
  }
}

.modal__close {
  position: absolute;
  top: 12px;
  right: 16px;
  font-size: 1.75rem;
  color: var(--color-text-light);
  transition: color var(--transition);
  line-height: 1;
}

.modal__close:hover {
  color: var(--color-danger);
}

.modal__title {
  font-family: var(--font-heading);
  font-size: 2.5rem;
  font-weight: 900;
  color: var(--color-primary);
  margin-bottom: 8px;
}

.modal__pronounce {
  font-size: 1rem;
  color: var(--color-text-light);
  margin-bottom: 16px;
  font-style: italic;
}

.modal__fact {
  font-size: 1rem;
  line-height: 1.7;
  margin-bottom: 16px;
  color: var(--color-text);
}

.modal__examples strong {
  display: block;
  margin-bottom: 8px;
  color: var(--color-text);
}

.modal__examples ul {
  list-style: disc;
  padding-left: 20px;
}

.modal__examples li {
  font-size: 0.9375rem;
  color: var(--color-text-light);
  margin-bottom: 4px;
}

/* ===== MEDIA QUERIES ===== */
@media (max-width: 1024px) {
  .hero__title-line--1 { font-size: 2.5rem; }
  .hero__title-line--2 { font-size: 4rem; }
  .hero__title-line--3 { font-size: 5.5rem; }

  .section__title { font-size: 2rem; }

  .alphabet__grid {
    grid-template-columns: repeat(6, 1fr);
  }
}

@media (max-width: 768px) {
  .header__nav {
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    background-color: var(--color-bg-alt);
    border-bottom: 1px solid var(--color-border);
    padding: 20px;
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: transform var(--transition), opacity var(--transition), visibility var(--transition);
  }

  .header__nav--open {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  .header__nav-list {
    flex-direction: column;
    gap: 16px;
    align-items: center;
  }

  .header__burger {
    display: flex;
  }

  .header__burger--active .header__burger-line:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }

  .header__burger--active .header__burger-line:nth-child(2) {
    opacity: 0;
  }

  .header__burger--active .header__burger-line:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  .hero__title-line--1 { font-size: 2rem; }
  .hero__title-line--2 { font-size: 3rem; }
  .hero__title-line--3 { font-size: 4rem; }

  .hero__subtitle { font-size: 1rem; }

  .section { padding: 60px 0; }
  .section__title { font-size: 1.75rem; }

  .alphabet__grid {
    grid-template-columns: repeat(5, 1fr);
    gap: 8px;
  }

  .alphabet__letter {
    font-size: 1.25rem;
  }

  .facts__slider {
    flex-direction: column;
    gap: 16px;
  }

  .facts__btn {
    order: 1;
  }

  .facts__slides {
    order: 0;
    min-height: 140px;
  }

  .facts__slide {
    padding: 24px 20px;
  }

  .typography__demos {
    grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
    gap: 16px;
  }

  .game__field {
    grid-template-columns: repeat(4, 1fr);
    max-width: 300px;
  }

  .footer__inner {
    flex-direction: column;
    text-align: center;
  }

  .footer__nav-list {
    justify-content: center;
  }
}

@media (max-width: 480px) {
  .hero__title-line--1 { font-size: 1.5rem; }
  .hero__title-line--2 { font-size: 2.25rem; }
  .hero__title-line--3 { font-size: 3rem; }

  .hero__btn {
    padding: 14px 32px;
    font-size: 1rem;
  }

  .section { padding: 40px 0; }
  .section__title { font-size: 1.5rem; }
  .section__desc { font-size: 1rem; margin-bottom: 32px; }

  .alphabet__grid {
    grid-template-columns: repeat(4, 1fr);
    gap: 6px;
  }

  .alphabet__letter {
    font-size: 1.125rem;
  }

  .game__info {
    gap: 16px;
  }

  .game__score,
  .game__timer,
  .game__target {
    font-size: 0.9375rem;
    padding: 8px 16px;
  }

  .game__field {
    grid-template-columns: repeat(4, 1fr);
    gap: 8px;
    max-width: 260px;
  }
}

/* ===== Typewriter Animation ===== */
.hero__title-char {
  display: inline-block;
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.3s ease, transform 0.3s ease;
}

.hero__title-char--visible {
  opacity: 1;
  transform: translateY(0);
}

/* Cursor blinking effect after typing */
.hero__title-cursor {
  display: inline-block;
  width: 3px;
  height: 1em;
  background-color: var(--color-accent);
  margin-left: 4px;
  vertical-align: text-bottom;
  animation: blink 0.8s step-end infinite;
}

@keyframes blink {
  50% {
    opacity: 0;
  }
}

/* ===== Scroll Animations ===== */
.section--hidden {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.section--visible {
  opacity: 1;
  transform: translateY(0);
}

@media (max-width: 360px) {
  .alphabet__grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 5px;
  }

  .alphabet__letter {
    font-size: 1rem;
  }

  .game__field {
    grid-template-columns: repeat(3, 1fr);
    max-width: 200px;
  }
}