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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: Inter, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  background: linear-gradient(180deg, #0d0d16 0%, #161625 100%);
  color: #e0e0e8;
  line-height: 1.6;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

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

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

/* ===== Container ===== */
.container {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 20px;
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 32px;
  border-radius: 12px;
  font-size: 1rem;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: transform 0.2s, box-shadow 0.2s;
  background: linear-gradient(135deg, #00d9ff, #00ff88);
  color: #0d0d16;
  text-decoration: none;
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 24px rgba(0, 217, 255, 0.4), 0 0 48px rgba(0, 255, 136, 0.2);
}

.btn:active {
  transform: translateY(0);
}

.btn--lg {
  padding: 16px 40px;
  font-size: 1.1rem;
  border-radius: 14px;
}

.btn--sm {
  padding: 10px 22px;
  font-size: 0.9rem;
  border-radius: 10px;
}

.btn--outline {
  background: transparent;
  border: 1.5px solid rgba(0, 217, 255, 0.5);
  color: #00d9ff;
}

.btn--outline:hover {
  background: rgba(0, 217, 255, 0.1);
  border-color: #00d9ff;
  box-shadow: 0 0 16px rgba(0, 217, 255, 0.2);
}

/* ===== Header ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(13, 13, 22, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.1rem;
}

.logo__text {
  background: linear-gradient(135deg, #00d9ff, #00ff88);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav {
  display: flex;
  gap: 28px;
}

.nav__link {
  font-size: 0.9rem;
  color: rgba(224, 224, 232, 0.7);
  transition: color 0.2s;
}

.nav__link:hover {
  color: #00d9ff;
}

.burger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 32px;
  height: 32px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.burger span {
  display: block;
  width: 100%;
  height: 2px;
  background: #e0e0e8;
  border-radius: 2px;
  transition: transform 0.3s, opacity 0.3s;
}

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

.burger.active span:nth-child(2) {
  opacity: 0;
}

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

/* ===== Hero ===== */
.hero {
  padding: 140px 0 80px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -200px;
  left: 50%;
  transform: translateX(-50%);
  width: 800px;
  height: 800px;
  background: radial-gradient(circle, rgba(0, 217, 255, 0.08) 0%, transparent 70%);
  pointer-events: none;
}

.hero__title {
  font-size: 3rem;
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 20px;
  background: linear-gradient(135deg, #ffffff 30%, #00d9ff 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero__sub {
  font-size: 1.15rem;
  color: rgba(224, 224, 232, 0.65);
  max-width: 560px;
  margin: 0 auto 36px;
  line-height: 1.7;
}

.hero__note {
  margin-top: 16px;
  font-size: 0.9rem;
  color: rgba(224, 224, 232, 0.45);
}

/* ===== Section Title ===== */
.section-title {
  text-align: center;
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 48px;
  background: linear-gradient(135deg, #ffffff 30%, #00d9ff 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ===== Features ===== */
.features {
  padding: 80px 0;
}

.features__grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.card {
  background: rgba(255, 255, 255, 0.06);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 16px;
  padding: 32px 24px;
  transition: transform 0.3s, border-color 0.3s;
}

.card:hover {
  transform: translateY(-4px);
  border-color: rgba(0, 217, 255, 0.25);
}

.card__icon {
  margin-bottom: 18px;
}

.card__title {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 10px;
  color: #fff;
}

.card__text {
  font-size: 0.9rem;
  color: rgba(224, 224, 232, 0.6);
  line-height: 1.6;
}

/* ===== How To ===== */
.howto {
  padding: 80px 0;
}

.steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-bottom: 40px;
}

.step {
  text-align: center;
  padding: 32px 20px;
}

.step__num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: linear-gradient(135deg, #00d9ff, #00ff88);
  color: #0d0d16;
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 18px;
}

.step__title {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 10px;
  color: #fff;
}

.step__text {
  font-size: 0.9rem;
  color: rgba(224, 224, 232, 0.6);
  line-height: 1.6;
}

.steps__cta {
  text-align: center;
}

/* ===== Pricing ===== */
.pricing {
  padding: 80px 0;
}

.pricing__grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-bottom: 32px;
}

.price-card {
  background: rgba(255, 255, 255, 0.06);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 16px;
  padding: 32px 24px;
  text-align: center;
  position: relative;
  transition: transform 0.3s, border-color 0.3s;
}

.price-card:hover {
  transform: translateY(-4px);
  border-color: rgba(0, 217, 255, 0.25);
}

.price-card--popular {
  border-color: rgba(0, 217, 255, 0.4);
  background: rgba(0, 217, 255, 0.08);
}

.price-card__badge {
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(135deg, #00d9ff, #00ff88);
  color: #0d0d16;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 4px 16px;
  border-radius: 20px;
  white-space: nowrap;
}

.price-card__period {
  font-size: 1rem;
  color: rgba(224, 224, 232, 0.65);
  margin-bottom: 12px;
}

.price-card__price {
  font-size: 2rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 6px;
}

.price-card__per {
  font-size: 0.85rem;
  color: rgba(0, 217, 255, 0.8);
  margin-bottom: 20px;
  min-height: 20px;
}

.pricing__note {
  text-align: center;
  font-size: 0.9rem;
  color: rgba(224, 224, 232, 0.5);
  margin-bottom: 24px;
}

.pricing__cta {
  text-align: center;
}

/* ===== Referral ===== */
.referral {
  padding: 80px 0;
}

.referral__card {
  background: linear-gradient(135deg, rgba(0, 217, 255, 0.1), rgba(0, 255, 136, 0.08));
  border: 1px solid rgba(0, 217, 255, 0.2);
  border-radius: 20px;
  padding: 56px 40px;
  text-align: center;
}

.referral__title {
  font-size: 1.8rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 16px;
}

.referral__text {
  font-size: 1.05rem;
  color: rgba(224, 224, 232, 0.65);
  max-width: 480px;
  margin: 0 auto 28px;
  line-height: 1.7;
}

/* ===== Auth ===== */
.auth {
  padding: 80px 0;
}

.auth__card {
  max-width: 440px;
  margin: 0 auto;
  background: rgba(255, 255, 255, 0.06);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 20px;
  padding: 36px 32px;
}

.auth__tabs {
  display: flex;
  gap: 4px;
  margin-bottom: 28px;
  background: rgba(255, 255, 255, 0.04);
  border-radius: 12px;
  padding: 4px;
}

.auth__tab {
  flex: 1;
  padding: 10px 0;
  background: none;
  border: none;
  cursor: pointer;
  font-size: 0.95rem;
  font-weight: 500;
  color: rgba(224, 224, 232, 0.5);
  border-radius: 10px;
  transition: background 0.2s, color 0.2s;
}

.auth__tab:hover {
  color: rgba(224, 224, 232, 0.8);
}

.auth__tab.active {
  background: rgba(0, 217, 255, 0.15);
  color: #00d9ff;
}

.auth__form {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.auth__input {
  width: 100%;
  padding: 14px 16px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 12px;
  color: #e0e0e8;
  font-size: 0.95rem;
  font-family: inherit;
  outline: none;
  transition: border-color 0.2s;
}

.auth__input::placeholder {
  color: rgba(224, 224, 232, 0.35);
}

.auth__input:focus {
  border-color: rgba(0, 217, 255, 0.5);
}

.auth__btn {
  width: 100%;
  margin-top: 4px;
}

.auth__error {
  color: #ff4d6a;
  font-size: 0.85rem;
  min-height: 0;
  transition: min-height 0.2s;
}

.auth__error:empty {
  display: none;
}

.auth__success {
  color: #00ff88;
  font-size: 0.85rem;
}

.auth__success:empty {
  display: none;
}

/* ===== FAQ ===== */
.faq {
  padding: 80px 0;
}

.faq__list {
  max-width: 720px;
  margin: 0 auto;
}

.faq__item {
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.faq__question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: 20px 0;
  background: none;
  border: none;
  cursor: pointer;
  color: #fff;
  font-size: 1rem;
  font-weight: 500;
  text-align: left;
  gap: 16px;
}

.faq__question:hover {
  color: #00d9ff;
}

.faq__arrow {
  flex-shrink: 0;
  transition: transform 0.3s;
}

.faq__item.active .faq__arrow {
  transform: rotate(180deg);
}

.faq__answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease, padding 0.35s ease;
}

.faq__item.active .faq__answer {
  max-height: 300px;
  padding-bottom: 20px;
}

.faq__answer p {
  font-size: 0.9rem;
  color: rgba(224, 224, 232, 0.6);
  line-height: 1.7;
}

/* ===== Footer ===== */
.footer {
  padding: 40px 0;
  border-top: 1px solid rgba(255, 255, 255, 0.06);
}

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

.footer__links {
  display: flex;
  gap: 24px;
}

.footer__links a {
  font-size: 0.9rem;
  color: rgba(224, 224, 232, 0.5);
  transition: color 0.2s;
}

.footer__links a:hover {
  color: #00d9ff;
}

.footer__copy {
  font-size: 0.8rem;
  color: rgba(224, 224, 232, 0.3);
}

/* ===== Fade-in Animation ===== */
.fade-in {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* ===== Mobile ===== */
@media (max-width: 1024px) {
  .features__grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .pricing__grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .btn--header {
    display: none;
  }

  .burger {
    display: flex;
  }

  .nav {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    bottom: 0;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 32px;
    background: rgba(13, 13, 22, 0.96);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s;
  }

  .nav.open {
    opacity: 1;
    pointer-events: auto;
  }

  .nav__link {
    font-size: 1.2rem;
  }

  .hero {
    padding: 120px 0 60px;
  }

  .hero__title {
    font-size: 2rem;
  }

  .hero__sub {
    font-size: 1rem;
  }

  .section-title {
    font-size: 1.6rem;
    margin-bottom: 36px;
  }

  .features__grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .steps {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .pricing__grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .referral__card {
    padding: 36px 24px;
  }

  .referral__title {
    font-size: 1.4rem;
  }

  .footer__inner {
    flex-direction: column;
    gap: 16px;
    text-align: center;
  }
}