/* ==========================================================================
   TEKNOPOLIS.AI — MVP one-page site
   Token warna & tipografi mengikuti BRAND_VISUAL_SPEC_V1.md.
   Tanpa framework, tanpa build step, tanpa request eksternal.
   ========================================================================== */

:root {
  /* Palet terkunci — spec §1 */
  --jet:      #0B0B0B;
  --charcoal: #1A1A1A;
  --graphite: #4A4A4A;
  --paper:    #E6E6E6;
  --accent:   #4C6EF5;
  --white:    #FFFFFF;

  /* Turunan untuk teks di atas latar gelap.
     Body dinaikkan ke .72 mengikuti standar keterbacaan yang sudah dikunci
     pada pipeline carousel — di bawah itu terasa redup pada layar kecil. */
  --on-dark-strong: rgba(255, 255, 255, .92);
  --on-dark-body:   rgba(255, 255, 255, .72);
  --on-dark-muted:  rgba(255, 255, 255, .55);
  --hairline:       rgba(255, 255, 255, .14);
  --hairline-dark:  rgba(11, 11, 11, .16);

  /* Space Grotesk & Inter dipakai bila terpasang di sistem pembaca.
     Tidak ada @font-face dan tidak ada Google Fonts — situs ini tidak boleh
     bergantung pada jaringan. Fallback dipilih yang karakternya paling dekat:
     geometris-netral, bukan playful. */
  --font-display: "Space Grotesk", "Inter", -apple-system, BlinkMacSystemFont,
                  "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-body:    "Inter", -apple-system, BlinkMacSystemFont,
                  "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;

  --wrap:    1120px;
  --gutter:  clamp(20px, 5vw, 64px);
  --section: clamp(72px, 11vw, 148px);
}

/* --------------------------------------------------------------- reset --- */

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

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--jet);
  color: var(--on-dark-strong);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  /* Cegah overflow horizontal dari elemen mana pun */
  overflow-x: hidden;
}

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

h1, h2, h3 {
  font-family: var(--font-display);
  font-weight: 600;
  letter-spacing: -.022em;
  line-height: 1.1;
  margin: 0;
  /* Judul panjang tidak boleh memaksa halaman melebar di layar sempit */
  overflow-wrap: break-word;
}

p  { margin: 0; }
ul { margin: 0; padding: 0; list-style: none; }

a { color: inherit; }

.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

/* ------------------------------------------------------- accessibility --- */

.visually-hidden {
  position: absolute;
  width: 1px; height: 1px;
  margin: -1px; padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
}

.skip-link {
  position: absolute;
  left: 16px; top: -100px;
  z-index: 100;
  padding: 12px 18px;
  background: var(--accent);
  color: var(--white);
  font-family: var(--font-display);
  font-size: 15px;
  text-decoration: none;
  border-radius: 2px;
  transition: top .15s ease;
}
.skip-link:focus { top: 16px; }

/* Fokus terlihat jelas di seluruh elemen interaktif */
a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 2px;
}

/* Hormati preferensi pengguna yang mengurangi gerak */
html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
    scroll-behavior: auto !important;
  }
}

/* --------------------------------------------------------------- header --- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(11, 11, 11, .88);
  backdrop-filter: saturate(140%) blur(10px);
  border-bottom: 1px solid var(--hairline);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  min-height: 68px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  flex-shrink: 0;
}
.brand-mark { width: 36px; height: 36px; border-radius: 50%; }
.brand-name {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 17px;
  letter-spacing: -.01em;
}

.site-nav ul {
  display: flex;
  align-items: center;
  gap: clamp(18px, 2.6vw, 34px);
}
.site-nav a {
  font-size: 15px;
  text-decoration: none;
  color: var(--on-dark-body);
  padding: 6px 0;
  border-bottom: 1px solid transparent;
  transition: color .16s ease, border-color .16s ease;
}
.site-nav a:hover { color: var(--white); border-bottom-color: var(--accent); }
.nav-external { color: var(--on-dark-muted); }

/* Tombol menu hanya muncul di layar sempit */
.nav-toggle {
  display: none;
  width: 44px; height: 44px;
  padding: 0;
  background: none;
  border: 1px solid var(--hairline);
  border-radius: 3px;
  cursor: pointer;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
}
.nav-toggle-bar {
  display: block;
  width: 18px; height: 1.5px;
  background: var(--on-dark-strong);
}

/* ----------------------------------------------------------------- hero --- */

.hero {
  padding-block: clamp(80px, 14vw, 176px) clamp(64px, 10vw, 128px);
  border-bottom: 1px solid var(--hairline);
}

.eyebrow {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 13px;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--on-dark-muted);
  margin-bottom: 28px;
}

.hero-title {
  font-size: clamp(44px, 8.5vw, 104px);
  line-height: 1.03;
  max-width: 15ch;
}

.hero-copy {
  margin-top: 30px;
  max-width: 54ch;
  font-size: clamp(17px, 1.9vw, 21px);
  line-height: 1.6;
  color: var(--on-dark-body);
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 44px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 50px;
  padding: 0 28px;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 15px;
  text-decoration: none;
  border: 1px solid transparent;
  border-radius: 3px;
  transition: background-color .16s ease, border-color .16s ease, color .16s ease;
}
.btn-primary {
  background: var(--white);
  color: var(--jet);
}
.btn-primary:hover { background: var(--paper); }
.btn-secondary {
  border-color: var(--hairline);
  color: var(--on-dark-body);
}
.btn-secondary:hover { border-color: var(--accent); color: var(--white); }

/* -------------------------------------------------------------- section --- */

.section { padding-block: var(--section); }
.section + .section { border-top: 1px solid var(--hairline); }

.section-head {
  display: flex;
  align-items: baseline;
  gap: 18px;
  margin-bottom: clamp(38px, 5vw, 62px);
}
.section-index {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 13px;
  letter-spacing: .16em;
  color: var(--accent);
}
.section-title { font-size: clamp(28px, 4vw, 44px); }

/* Satu pita terang untuk memberi ritme, meniru selang-seling carousel */
.section-light {
  background: var(--paper);
  color: var(--jet);
  border-top: none;
}
.section-light + .section { border-top: none; }

/* ---------------------------------------------------------------- cards --- */

.cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: clamp(20px, 2.6vw, 34px);
}

/* Kartu berbasis teks — lihat catatan di index.html.
   Garis aksen tipis di sisi atas menggantikan peran cover image sebagai
   penanda visual, tanpa menambah bobot. */
.card {
  display: flex;
  flex-direction: column;
  padding: 30px 28px 34px;
  background: var(--charcoal);
  border: 1px solid var(--hairline);
  border-top: 2px solid var(--accent);
  border-radius: 3px;
}

.card-kicker {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 12px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--on-dark-muted);
  margin-bottom: 14px;
}
.card-title { font-size: 22px; line-height: 1.2; }
.card-copy {
  margin-top: 16px;
  font-size: 15.5px;
  line-height: 1.62;
  color: var(--on-dark-body);
}

/* ---------------------------------------------------------------- focus --- */

.focus-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: clamp(28px, 4vw, 56px);
}
.focus-item { border-top: 1px solid var(--hairline-dark); padding-top: 24px; }
.focus-title { font-size: 22px; margin-bottom: 14px; }
.focus-copy {
  font-size: 16px;
  line-height: 1.62;
  color: var(--graphite);
  max-width: 34ch;
}

/* ---------------------------------------------------------------- about --- */

.about-copy {
  max-width: 62ch;
  font-size: clamp(18px, 2.1vw, 23px);
  line-height: 1.58;
  color: var(--on-dark-body);
}

/* ----------------------------------------------------------- disclosure --- */

/* Jelas dan mudah dibaca, tetapi tidak dominan — bukan banner iklan. */
.disclosure { padding-block: clamp(48px, 6vw, 76px); }
.disclosure-title {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 12px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--on-dark-muted);
  margin-bottom: 16px;
}
.disclosure-copy {
  max-width: 68ch;
  font-size: 15px;
  line-height: 1.62;
  color: var(--on-dark-body);
}

/* --------------------------------------------------------------- footer --- */

.site-footer {
  border-top: 1px solid var(--hairline);
  padding-block: clamp(48px, 6vw, 72px);
}
.footer-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  justify-content: space-between;
  gap: 32px;
}
.footer-name {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 17px;
}
.footer-line {
  margin-top: 6px;
  font-size: 15px;
  color: var(--on-dark-muted);
}
.footer-nav ul { display: flex; flex-direction: column; gap: 10px; }
.footer-nav a {
  font-size: 15px;
  color: var(--on-dark-body);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color .16s ease, border-color .16s ease;
}
.footer-nav a:hover { color: var(--white); border-bottom-color: var(--accent); }
.footer-legal { font-size: 14px; color: var(--on-dark-muted); }

/* ------------------------------------------------------------------ 404 --- */

/* Kelas 404 ditaruh di sini, bukan sebagai <style> di 404.html.
   CSP situs ini tidak mengizinkan inline style — lihat catatan di `_headers`. */

.notfound {
  min-height: 78vh;
  display: flex;
  align-items: center;
  padding-block: clamp(64px, 10vw, 120px);
}
.notfound-mark {
  width: 56px; height: 56px;
  border-radius: 50%;
  margin-bottom: 34px;
}
.notfound-title {
  font-size: clamp(38px, 6.5vw, 68px);
  line-height: 1.05;
}
.notfound-copy {
  margin-top: 22px;
  max-width: 44ch;
  font-size: clamp(16px, 1.8vw, 19px);
  line-height: 1.6;
  color: var(--on-dark-body);
}
.notfound-cta { margin-top: 38px; }
.notfound-footer { border-top: 1px solid var(--hairline); }

/* ====================================================== responsive ======== */

/* Tablet */
@media (max-width: 900px) {
  .cards,
  .focus-list { grid-template-columns: repeat(2, 1fr); }
  .cards .card:last-child { grid-column: 1 / -1; }
  .focus-list { gap: 32px; }
}

/* Mobile */
@media (max-width: 680px) {
  body { font-size: 16px; }

  .nav-toggle { display: flex; }

  /* Nav tertutup secara default; dibuka lewat tombol.
     Memakai [hidden]-style display none agar tautan yang tersembunyi
     tidak bisa difokus dengan keyboard. */
  .site-nav {
    display: none;
    position: absolute;
    left: 0; right: 0;
    top: 100%;
    background: var(--jet);
    border-bottom: 1px solid var(--hairline);
    padding: 8px var(--gutter) 20px;
  }
  .site-nav.is-open { display: block; }
  .site-nav ul { flex-direction: column; align-items: stretch; gap: 0; }
  .site-nav li + li { border-top: 1px solid var(--hairline); }
  .site-nav a { display: block; padding: 15px 0; font-size: 16px; }
  .site-nav a:hover { border-bottom-color: transparent; }

  .header-inner { position: relative; }

  .hero-title { max-width: 100%; }
  .cta-row { gap: 12px; }
  .btn { flex: 1 1 auto; min-width: 150px; }

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

  .section-head { gap: 14px; margin-bottom: 32px; }

  .footer-inner { flex-direction: column; gap: 26px; }
}