/* ═══════════════════════════════════════
   ASTERI ACADEMIC CONSULTING
   Design: Swiss Grid + Brutalist Accents
   Palette: Deep Blue / White / Yellow / Red
   ═══════════════════════════════════════ */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;600;700;900&family=Noto+Sans+SC:wght@300;400;500;700;900&display=swap');

:root {
  --blue: #0B1F3A;
  --blue-light: #132D52;
  --blue-dark: #061220;
  --white: #F5F5F0;
  --white-pure: #FFFFFF;
  --yellow: #FFD23F;
  --yellow-light: #FFE680;
  --red: #FF4D2E;
  --red-light: #FF7A63;
  --gray: #8899AA;
  --gray-light: #AABBCC;
  --gray-dark: #445566;
  --border: 2px solid var(--white);
  --border-thick: 4px solid var(--white);
  --radius: 0px;
  --radius-sm: 2px;
  --font-en: 'Inter', system-ui, sans-serif;
  --font-zh: 'Noto Sans SC', 'Inter', system-ui, sans-serif;
  --gap: clamp(1rem, 4vw, 4rem);
  --section-pad: clamp(4rem, 10vw, 8rem);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--font-en);
  background: var(--blue);
  color: var(--white);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
body.lang-zh { font-family: var(--font-zh); }

/* ── Typography ── */
h1, h2, h3, h4 { font-weight: 700; line-height: 1.1; letter-spacing: -0.02em; }
.kicker {
  font-family: var(--font-en);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.2em;
  color: var(--yellow);
  text-transform: uppercase;
  margin-bottom: 0.75rem;
}
.section-title {
  font-size: clamp(2rem, 6vw, 4rem);
  font-weight: 900;
  margin-bottom: 1rem;
}
.section-subtitle {
  font-size: clamp(1rem, 2.5vw, 1.25rem);
  color: var(--gray-light);
  max-width: 36rem;
}

/* ── Layout Helpers ── */
.container { width: min(90%, 1200px); margin-inline: auto; }
.section { padding-block: var(--section-pad); }
.section-header { margin-bottom: var(--gap); }

/* ── Brutalist Divider ── */
.divider {
  width: 4rem;
  height: 4px;
  background: var(--yellow);
  margin: 1rem 0 2rem;
}
.divider--center { margin-inline: auto; }

/* ═══════════════════════════════════════
   NAVIGATION
   ═══════════════════════════════════════ */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  padding: 1.25rem 0;
  background: rgba(11, 31, 58, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(255,255,255,0.08);
  transition: padding 0.3s;
}
.nav--scrolled { padding: 0.75rem 0; }
.nav__inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: min(90%, 1200px);
  margin-inline: auto;
}
.nav__logo {
  font-family: var(--font-en);
  font-size: 1.25rem;
  font-weight: 900;
  letter-spacing: 0.05em;
  color: var(--white);
  text-decoration: none;
}
.nav__logo span { color: var(--yellow); }
.nav__links {
  display: flex;
  gap: 2rem;
  align-items: center;
  list-style: none;
}
.nav__links a {
  color: var(--gray-light);
  text-decoration: none;
  font-size: 0.875rem;
  font-weight: 500;
  letter-spacing: 0.03em;
  transition: color 0.2s;
  text-transform: uppercase;
}
.nav__links a:hover { color: var(--white); }
.nav__lang {
  background: none;
  border: var(--border);
  border-color: var(--gray-dark);
  color: var(--white);
  padding: 0.4rem 1rem;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  cursor: pointer;
  transition: all 0.2s;
  text-transform: uppercase;
}
.nav__lang:hover { border-color: var(--white); background: rgba(255,255,255,0.05); }
.nav__mobile { display: none; background: none; border: none; color: var(--white); font-size: 1.5rem; cursor: pointer; }
.nav__links--open {
  display: flex !important;
  position: absolute;
  top: 100%;
  left: 0; right: 0;
  flex-direction: column;
  background: rgba(11,31,58,0.98);
  padding: 1.5rem 2rem;
  gap: 1.25rem;
  border-bottom: 1px solid rgba(255,255,255,0.08);
}

/* ═══════════════════════════════════════
   HERO
   ═══════════════════════════════════════ */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: 4rem;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -30%;
  width: 80vw;
  height: 200vh;
  background: radial-gradient(ellipse at center, rgba(255,210,63,0.06) 0%, transparent 70%);
  pointer-events: none;
}
.hero__grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--gap);
  align-items: center;
}
.hero__content { position: relative; z-index: 2; }
.hero__kicker {
  font-family: var(--font-en);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.25em;
  color: var(--yellow);
  margin-bottom: 1.5rem;
}
.hero__title {
  font-size: clamp(3rem, 8vw, 6rem);
  font-weight: 900;
  line-height: 0.95;
  margin-bottom: 1.5rem;
}
.hero__title .line2 {
  display: block;
  position: relative;
  left: 0.5em;
}
.hero__title em {
  font-style: normal;
  color: var(--yellow);
  -webkit-text-fill-color: transparent;
  -webkit-text-stroke: 1.5px var(--yellow);
  margin-left: -0.05em;
}
.hero__subtitle {
  font-size: clamp(1rem, 2vw, 1.25rem);
  color: var(--gray-light);
  max-width: 28rem;
  margin-bottom: 2.5rem;
}
.hero__cta {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}
.btn {
  display: inline-block;
  padding: 0.85rem 2rem;
  font-size: 0.9rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-decoration: none;
  text-transform: uppercase;
  cursor: pointer;
  transition: all 0.2s;
  border: none;
  font-family: inherit;
}
.btn--primary {
  background: var(--yellow);
  color: var(--blue-dark);
}
.btn--primary:hover { background: var(--yellow-light); transform: translateY(-2px); }
.btn--outline {
  background: transparent;
  color: var(--white);
  border: var(--border);
}
.btn--outline:hover { background: rgba(255,255,255,0.06); transform: translateY(-2px); }
.btn--submit {
  background: var(--white);
  color: var(--blue-dark);
  width: 100%;
  padding: 1rem;
  font-size: 0.85rem;
}
.btn--submit:hover { background: var(--yellow); }

.hero__visual {
  position: relative;
  z-index: 2;
  display: flex;
  justify-content: center;
  align-items: center;
}
.hero__illustration {
  width: 100%;
  max-width: 500px;
  aspect-ratio: 1;
}

/* ═══════════════════════════════════════
   SERVICES CARDS
   ═══════════════════════════════════════ */
.services { position: relative; }
.services__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  margin-top: var(--gap);
}
.service-card {
  background: var(--blue-light);
  border: 1px solid rgba(255,255,255,0.06);
  padding: 2.5rem 2rem;
  position: relative;
  transition: all 0.3s;
  /* brutalist: strong border on hover */
}
.service-card:hover {
  transform: translateY(-4px);
  border-color: var(--yellow);
  box-shadow: 8px 8px 0 rgba(255,210,63,0.15);
}
.service-card__icon {
  width: 48px;
  height: 48px;
  margin-bottom: 1.5rem;
  color: var(--yellow);
}
.service-card__en {
  font-family: var(--font-en);
  font-size: 0.65rem;
  letter-spacing: 0.2em;
  color: var(--gray);
  text-transform: uppercase;
  margin-bottom: 0.25rem;
}
.service-card__title {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
}
.service-card__desc {
  font-size: 0.95rem;
  color: var(--gray-light);
  margin-bottom: 1.25rem;
  line-height: 1.7;
}
.service-card__points {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}
.service-card__points li {
  font-size: 0.85rem;
  color: var(--gray);
  padding-left: 1.25rem;
  position: relative;
}
.service-card__points li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.45em;
  width: 6px;
  height: 6px;
  background: var(--yellow);
}

/* ═══════════════════════════════════════
   PROCESS
   ═══════════════════════════════════════ */
.process { background: var(--blue-dark); }
.process__grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  margin-top: var(--gap);
  border: var(--border);
  border-color: rgba(255,255,255,0.1);
}
.process-step {
  background: var(--blue);
  padding: 2.5rem 2rem;
  position: relative;
  transition: background 0.3s;
}
.process-step:hover { background: var(--blue-light); }
.process-step__num {
  font-family: var(--font-en);
  font-size: 3rem;
  font-weight: 900;
  color: var(--yellow);
  opacity: 0.3;
  line-height: 1;
  margin-bottom: 0.5rem;
}
.process-step__title {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}
.process-step__desc {
  font-size: 0.9rem;
  color: var(--gray-light);
}

/* ═══════════════════════════════════════
   WHY US
   ═══════════════════════════════════════ */
.why { position: relative; }
.why__stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  margin: var(--gap) 0;
  border: var(--border);
  border-color: rgba(255,255,255,0.08);
}
.stat {
  background: var(--blue-light);
  padding: 2.5rem 2rem;
  text-align: center;
}
.stat__num {
  font-family: var(--font-en);
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 900;
  color: var(--yellow);
  line-height: 1;
  margin-bottom: 0.5rem;
}
.stat__label {
  font-size: 0.9rem;
  color: var(--gray-light);
}
.why__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  margin-top: var(--gap);
}
.why-item__title {
  font-family: var(--font-en);
  font-size: 0.7rem;
  letter-spacing: 0.2em;
  color: var(--yellow);
  text-transform: uppercase;
  margin-bottom: 0.5rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.why-item__title::before {
  content: '';
  width: 12px;
  height: 2px;
  background: var(--yellow);
}
.why-item__heading {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}
.why-item__desc {
  font-size: 0.95rem;
  color: var(--gray-light);
}

/* ═══════════════════════════════════════
   CONTACT
   ═══════════════════════════════════════ */
.contact { background: var(--blue-dark); }
.contact__grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--gap);
  margin-top: var(--gap);
}
.contact-form {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}
.form-group label {
  display: block;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 0.5rem;
  color: var(--gray-light);
}
.form-group input,
.form-group textarea {
  width: 100%;
  background: rgba(255,255,255,0.04);
  border: 1px solid rgba(255,255,255,0.12);
  color: var(--white);
  padding: 0.85rem 1rem;
  font-size: 0.95rem;
  font-family: inherit;
  transition: border-color 0.2s;
  outline: none;
}
.form-group input:focus,
.form-group textarea:focus {
  border-color: var(--yellow);
}
.form-group textarea { min-height: 120px; resize: vertical; }
.contact-info {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  justify-content: center;
  padding-left: 2rem;
  border-left: 1px solid rgba(255,255,255,0.08);
}
.contact-info__item h4 {
  font-family: var(--font-en);
  font-size: 0.65rem;
  letter-spacing: 0.2em;
  color: var(--gray);
  text-transform: uppercase;
  margin-bottom: 0.25rem;
}
.contact-info__item p {
  font-size: 1rem;
  color: var(--gray-light);
}
.contact-info__item--qrcode {
  flex-direction: row;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}
.contact-info__qrcode {
  flex-shrink: 0;
}
.qrcode-placeholder {
  width: 90px;
  height: 90px;
  background: var(--blue-light);
  border: 2px dashed var(--yellow);
  border-radius: 8px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 0.4rem;
}
.qrcode-placeholder span {
  font-size: 0.7rem;
  color: var(--white);
  font-weight: 700;
  line-height: 1.3;
}
.qrcode-placeholder small {
  font-size: 0.55rem;
  color: var(--gray);
  margin-top: 0.2rem;
  line-height: 1.2;
}

@media (max-width: 900px) {
  .contact-info__item--qrcode {
    flex-direction: column;
    align-items: flex-start;
    gap: 1rem;
  }
}

/* ═══════════════════════════════════════
   FOOTER
   ═══════════════════════════════════════ */
.footer {
  border-top: 1px solid rgba(255,255,255,0.06);
  padding: 3rem 0;
}
.footer__inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
  width: min(90%, 1200px);
  margin-inline: auto;
}
.footer__tagline {
  font-size: 0.9rem;
  color: var(--gray);
}
.footer__copy {
  font-size: 0.8rem;
  color: var(--gray-dark);
}

/* ═══════════════════════════════════════
   RESPONSIVE
   ═══════════════════════════════════════ */
@media (max-width: 900px) {
  .nav__links { display: none; }
  .nav__mobile { display: block; }
  .hero__grid { grid-template-columns: 1fr; }
  .hero__visual { display: none; }
  .services__grid { grid-template-columns: 1fr; }
  .process__grid { grid-template-columns: repeat(2, 1fr); }
  .contact__grid { grid-template-columns: 1fr; }
  .contact-info { border-left: none; border-top: 1px solid rgba(255,255,255,0.08); padding-left: 0; padding-top: 2rem; }
  .why__grid { grid-template-columns: 1fr; }
  .why__stats { grid-template-columns: repeat(3, 1fr); }
}

@media (max-width: 600px) {
  .process__grid { grid-template-columns: 1fr; }
  .why__stats { grid-template-columns: 1fr; }
  .hero__cta { flex-direction: column; }
  .hero__title { font-size: clamp(2rem, 10vw, 3.5rem); }
  .footer__inner { flex-direction: column; text-align: center; }
}

/* ── Fade-in Animation ── */
[data-animate] {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}
[data-animate].visible {
  opacity: 1;
  transform: translateY(0);
}