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

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, "Microsoft YaHei", "PingFang SC", "Helvetica Neue", Arial, sans-serif;
  color: #2d3436;
  background: #ffffff;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

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

ul {
  list-style: none;
}

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

/* ========== Layout ========== */
.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 80px 0;
}

.section--gray {
  background: #f5f5f5;
}

.section__title {
  font-size: 28px;
  font-weight: 600;
  text-align: center;
  margin-bottom: 12px;
}

.section__subtitle {
  text-align: center;
  color: #636e72;
  margin-bottom: 48px;
  font-size: 15px;
}

/* ========== Header ========== */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: #ffffff;
  border-bottom: 1px solid #eee;
}

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

.header__logo {
  font-size: 20px;
  font-weight: 700;
  color: #2d3436;
  letter-spacing: 1px;
}

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

.header__nav a {
  font-size: 15px;
  color: #636e72;
  transition: color 0.2s;
  position: relative;
}

.header__nav a:hover,
.header__nav a.active {
  color: #2d3436;
}

.header__nav a.active::after {
  content: "";
  position: absolute;
  bottom: -4px;
  left: 0;
  right: 0;
  height: 2px;
  background: #0984e3;
}

/* Hamburger */
.header__hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 4px;
  background: none;
  border: none;
}

.header__hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: #2d3436;
  transition: transform 0.3s, opacity 0.3s;
}

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

.header__hamburger.open span:nth-child(2) {
  opacity: 0;
}

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

/* ========== Hero ========== */
.hero {
  padding: 120px 0 100px;
  text-align: center;
}

.hero__title {
  font-size: 42px;
  font-weight: 700;
  margin-bottom: 20px;
  letter-spacing: 2px;
}

.hero__desc {
  font-size: 18px;
  color: #636e72;
  max-width: 560px;
  margin: 0 auto 40px;
}

.hero__cta {
  display: inline-block;
  padding: 12px 36px;
  background: #0984e3;
  color: #fff;
  border-radius: 4px;
  font-size: 15px;
  transition: background 0.2s;
}

.hero__cta:hover {
  background: #0770c2;
}

/* ========== Cards ========== */
.cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.card {
  background: #fff;
  border: 1px solid #eee;
  border-radius: 4px;
  padding: 36px 28px;
  transition: box-shadow 0.3s;
}

.card:hover {
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
}

.card__icon {
  width: 48px;
  height: 48px;
  background: #f0f7ff;
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  font-size: 22px;
  color: #0984e3;
}

.card__title {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 10px;
}

.card__text {
  font-size: 14px;
  color: #636e72;
  line-height: 1.8;
}

/* ========== CTA Banner ========== */
.cta-banner {
  text-align: center;
  padding: 80px 0;
}

.cta-banner__title {
  font-size: 24px;
  font-weight: 600;
  margin-bottom: 16px;
}

.cta-banner__text {
  color: #636e72;
  margin-bottom: 32px;
  font-size: 15px;
}

.cta-banner__btn {
  display: inline-block;
  padding: 12px 36px;
  border: 2px solid #2d3436;
  color: #2d3436;
  border-radius: 4px;
  font-size: 15px;
  transition: background 0.2s, color 0.2s;
}

.cta-banner__btn:hover {
  background: #2d3436;
  color: #fff;
}

/* ========== About Page ========== */
.about-intro {
  max-width: 720px;
  margin: 0 auto;
  text-align: center;
  font-size: 15px;
  color: #636e72;
  line-height: 2;
}

.values {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
  text-align: center;
}

.value-item {
  padding: 36px 20px;
}

.value-item__icon {
  width: 56px;
  height: 56px;
  background: #f0f7ff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 20px;
  font-size: 24px;
  color: #0984e3;
}

.value-item__title {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 8px;
}

.value-item__text {
  font-size: 14px;
  color: #636e72;
}

/* ========== Contact Page ========== */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: start;
}

.contact-info {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.contact-info__item {
  display: flex;
  gap: 16px;
  align-items: flex-start;
}

.contact-info__icon {
  width: 40px;
  height: 40px;
  background: #f0f7ff;
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  color: #0984e3;
  font-size: 16px;
}

.contact-info__label {
  font-size: 13px;
  color: #b2bec3;
  margin-bottom: 2px;
}

.contact-info__value {
  font-size: 15px;
}

/* Form */
.contact-form {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.form-group label {
  font-size: 14px;
  font-weight: 500;
}

.form-group input,
.form-group textarea {
  padding: 10px 14px;
  border: 1px solid #ddd;
  border-radius: 4px;
  font-size: 14px;
  font-family: inherit;
  color: #2d3436;
  transition: border-color 0.2s;
  outline: none;
}

.form-group input:focus,
.form-group textarea:focus {
  border-color: #0984e3;
}

.form-group textarea {
  min-height: 120px;
  resize: vertical;
}

.contact-form__btn {
  align-self: flex-start;
  padding: 10px 32px;
  background: #0984e3;
  color: #fff;
  border: none;
  border-radius: 4px;
  font-size: 15px;
  cursor: pointer;
  transition: background 0.2s;
}

.contact-form__btn:hover {
  background: #0770c2;
}

/* ========== Footer ========== */
.footer {
  border-top: 1px solid #eee;
  padding: 24px 0;
  text-align: center;
  font-size: 13px;
  color: #b2bec3;
}

.footer a {
  color: #b2bec3;
}

.footer a:hover {
  color: #636e72;
}

/* ========== Responsive ========== */
@media (max-width: 768px) {
  .header__hamburger {
    display: flex;
  }

  .header__nav {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: #fff;
    flex-direction: column;
    padding: 16px 24px;
    gap: 16px;
    border-bottom: 1px solid #eee;
  }

  .header__nav.open {
    display: flex;
  }

  .hero {
    padding: 80px 0 60px;
  }

  .hero__title {
    font-size: 28px;
  }

  .hero__desc {
    font-size: 15px;
  }

  .cards,
  .values {
    grid-template-columns: 1fr;
  }

  .contact-grid {
    grid-template-columns: 1fr;
  }

  .section {
    padding: 48px 0;
  }
}

@media (max-width: 480px) {
  .hero__title {
    font-size: 24px;
  }

  .section__title {
    font-size: 22px;
  }
}