/* ==========================================================
   Birlikte Technologies — site styles (no frameworks)
   ========================================================== */

:root {
  --navy-900: #0b1f3a;
  --navy-700: #0f4c81;
  --red: #e81c2e;
  --blue: #2563eb;
  --teal: #1b78a6;
  --ink: #0b1f3a;
  --text: #2d3748;
  --muted: #5a6577;
  --line: #edf2f7;
  --tint: #f8faff;
  --white: #fff;

  --font: -apple-system, BlinkMacSystemFont, "SF Pro Text", "SF Pro Display", "Helvetica Neue", Helvetica, Arial, sans-serif;
  --radius: 14px;
  --radius-lg: 24px;
  --shadow: 0 20px 40px rgba(0, 0, 0, .08);
  --nav-h: 70px;
  --gradient-navy: linear-gradient(to right, var(--navy-900), var(--navy-700));
}

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

html { scroll-behavior: smooth; scroll-padding-top: var(--nav-h); }

body {
  margin: 0;
  font-family: var(--font);
  font-size: 17px;
  line-height: 1.65;
  color: var(--text);
  background: var(--white);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, p, ul { margin: 0; }
ul { padding: 0; list-style: none; }
a { color: inherit; text-decoration: none; }
img, svg { display: block; max-width: 100%; }
:focus-visible { outline: 3px solid var(--blue); outline-offset: 3px; border-radius: 4px; }

.container { width: min(1180px, 100% - 48px); margin-inline: auto; }

.skip-link {
  position: absolute; left: -9999px; top: 8px; z-index: 3000;
  background: var(--white); color: var(--ink); padding: 8px 14px; border-radius: 6px;
}
.skip-link:focus { left: 8px; }

.accent-red { color: var(--red); }
.accent-blue { color: var(--blue); }

/* ---------- Buttons ---------- */
.btn {
  display: inline-block;
  padding: 12px 26px;
  border: 1px solid transparent;
  border-radius: 10px;
  font: 700 16px/1.2 var(--font);
  cursor: pointer;
  transition: transform .2s, background-color .2s, border-color .2s, box-shadow .2s;
}
.btn:hover { transform: translateY(-2px); }
.btn-primary { background: var(--blue); color: var(--white); box-shadow: 0 8px 20px rgba(37, 99, 235, .3); }
.btn-primary:hover { background: #1d4fd8; }
.btn-ghost { border-color: rgba(255, 255, 255, .5); color: var(--white); }
.btn-ghost:hover { background: rgba(255, 255, 255, .1); border-color: var(--white); }

/* ---------- Navbar ---------- */
.navbar {
  position: fixed; inset: 0 0 auto 0; z-index: 2000;
  height: var(--nav-h);
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 clamp(20px, 4vw, 48px);
  border-bottom: 1px solid rgba(255, 255, 255, .08);
  transition: transform .35s ease, background .35s ease, box-shadow .35s ease;
}
.navbar.scrolled { background: var(--gradient-navy); box-shadow: 0 6px 24px rgba(0, 0, 0, .25); }
.navbar.nav-hidden { transform: translateY(-110%); }

.brand { display: inline-flex; align-items: center; gap: 10px; color: var(--white); }
/* The logo file has a white background, so it sits on a white chip to read on the navy bar. */
.brand-mark { width: 74px; height: 42px; padding: 3px 6px; object-fit: contain; background: var(--white); border-radius: 8px; }
.brand-name { display: flex; flex-direction: column; line-height: 1.05; }
.brand-name b { font-size: 19px; font-weight: 700; letter-spacing: 3px; text-transform: uppercase; color: var(--white); }
.brand-name small { font-size: 10px; letter-spacing: 3.6px; text-transform: uppercase; color: #6cc4f5; }

.nav-links ul { display: flex; align-items: center; gap: clamp(16px, 2.4vw, 34px); }
.nav-links a {
  position: relative; color: var(--white); font-size: 16px; font-weight: 700; letter-spacing: .3px; padding: 6px 0;
}
.nav-links a::after {
  content: ""; position: absolute; left: 0; bottom: 0; width: 100%; height: 2px;
  background: var(--red); transform: scaleX(0); transform-origin: left; transition: transform .25s;
}
.nav-links a:hover::after, .nav-links a.active::after { transform: scaleX(1); }
.nav-links .nav-cta { padding: 8px 18px; border: 1px solid rgba(255, 255, 255, .5); border-radius: 8px; }
.nav-links .nav-cta::after { display: none; }
.nav-links .nav-cta:hover { background: var(--white); color: var(--ink); }

.nav-toggle {
  display: none; width: 44px; height: 44px; padding: 10px;
  background: none; border: 0; cursor: pointer; z-index: 2010;
}
.nav-toggle span {
  display: block; height: 3px; margin: 4px 0; border-radius: 2px; background: var(--white);
  transition: transform .3s, opacity .3s;
}
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.nav-backdrop {
  position: fixed; inset: 0; z-index: 1990; background: rgba(0, 0, 0, .5);
  opacity: 0; visibility: hidden; transition: opacity .3s, visibility .3s;
}

/* ---------- Hero ---------- */
.hero {
  position: relative; min-height: 100vh; min-height: 100svh;
  display: flex; align-items: center; justify-content: center;
  padding: calc(var(--nav-h) + 40px) 24px 80px;
  background: radial-gradient(ellipse at 50% 120%, #0f2f57 0%, #050b16 55%, #000 100%);
  color: var(--white); text-align: center; overflow: hidden;
}
.hero-canvas { position: absolute; inset: 0; width: 100%; height: 100%; }
.hero-content { position: relative; max-width: 860px; }
.hero h1 { font-size: clamp(36px, 6vw, 68px); line-height: 1.1; font-weight: 800; }
.hero .accent-blue { color: #6ea8ff; }
.hero .accent-red { color: #ff5a67; }
.hero-sub { margin: 22px auto 34px; max-width: 620px; font-size: clamp(17px, 2vw, 20px); color: rgba(255, 255, 255, .8); }
.hero-actions { display: flex; flex-wrap: wrap; gap: 14px; justify-content: center; }

.scroll-cue {
  position: absolute; bottom: 26px; left: 50%; width: 26px; height: 42px; margin-left: -13px;
  border: 2px solid rgba(255, 255, 255, .5); border-radius: 14px;
}
.scroll-cue span {
  position: absolute; top: 7px; left: 50%; width: 4px; height: 8px; margin-left: -2px;
  border-radius: 2px; background: var(--white); animation: cue 1.8s infinite;
}
@keyframes cue { 0% { opacity: 1; transform: translateY(0); } 100% { opacity: 0; transform: translateY(14px); } }

/* ---------- Sections ---------- */
/* overflow-x: clip keeps off-screen carousel cards from widening the mobile layout viewport */
.section { padding: clamp(60px, 9vw, 110px) 0; overflow-x: clip; }
.section-tint { background: radial-gradient(circle at 100% 0%, var(--tint), var(--white)); }

.section-head { text-align: center; max-width: 860px; margin: 0 auto clamp(36px, 5vw, 60px); }
.eyebrow {
  font-size: 15px; font-weight: 700; letter-spacing: 2px; text-transform: uppercase; color: var(--ink); margin-bottom: 8px;
}
.eyebrow-light { color: #8fc4f2; margin-bottom: 18px; }
.section-head h2 { font-size: clamp(30px, 4.6vw, 45px); line-height: 1.2; font-weight: 800; }
.section-sub { margin-top: 16px; color: var(--muted); }

/* ---------- About ---------- */
.about-media {
  display: grid; place-items: center; padding: clamp(16px, 3vw, 32px);
  background: var(--white); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow);
}
.about-media img { width: min(620px, 100%); height: auto; }

.about-overview { margin: 44px 0 34px; }
.about-overview h3 { font-size: 24px; color: var(--ink); margin-bottom: 10px; }
.about-overview p { text-align: justify; }
.about-overview strong { color: var(--ink); }

.card-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.card {
  padding: 24px; background: var(--white); border: 1px solid var(--line); border-radius: var(--radius);
  transition: transform .3s, box-shadow .3s, border-color .3s;
}
.card:hover { transform: translateY(-6px); box-shadow: var(--shadow); border-color: transparent; }
.card h4 { font-size: 19px; color: var(--ink); margin-bottom: 8px; }
.card p { margin-bottom: 14px; }
.link-more { font-weight: 700; color: var(--navy-700); border-bottom: 2px solid currentColor; }
.link-more span { display: inline-block; transition: transform .2s; }
.link-more:hover span { transform: translateX(4px); }

/* ---------- Coverflow carousel (services + insight) ---------- */
.coverflow { position: relative; height: 480px; margin-inline: auto; max-width: 1180px; outline: none; }
.cf-track { position: relative; height: 100%; }

.cf-card {
  position: absolute; top: 50%; left: 50%;
  width: 310px; margin: -215px 0 0 -155px; height: 430px;
  display: flex; flex-direction: column;
  background: var(--white); border: 1px solid rgba(11, 31, 58, .08); border-radius: var(--radius-lg);
  box-shadow: var(--shadow); overflow: hidden; cursor: pointer;
  transition: transform .6s cubic-bezier(.22, .8, .3, 1), opacity .6s, filter .6s;
  will-change: transform;
}
.cf-card.is-active { cursor: default; }
.cf-card:not(.is-active) { filter: saturate(.7); }

.cf-art { position: relative; flex: 0 0 150px; display: grid; place-items: center; color: var(--white); }
.cf-art svg { width: 56px; height: 56px; fill: none; stroke: currentColor; stroke-width: 1.5; stroke-linecap: round; stroke-linejoin: round; }
.cf-tag {
  position: absolute; left: 16px; bottom: 12px; padding: 4px 10px; border-radius: 6px;
  background: var(--blue); font-size: 11px; font-weight: 700; letter-spacing: 1px; text-transform: uppercase;
}
.cf-body { flex: 1; padding: 20px 22px; display: flex; flex-direction: column; }
.cf-body h3 { font-size: 20px; color: var(--ink); margin-bottom: 6px; }
.cf-body p { font-size: 15px; line-height: 1.5; margin-bottom: 8px; }
.cf-body ul { font-size: 15px; line-height: 1.75; }
.cf-body li::before { content: "•"; color: var(--red); margin-right: 8px; }
.cf-body .link-more { margin-top: auto; align-self: flex-start; font-size: 15px; }

.cf-arrow {
  position: absolute; top: 50%; z-index: 20; width: 46px; height: 46px; margin-top: -23px;
  border: 1px solid var(--line); border-radius: 50%; background: var(--white); color: var(--ink);
  font-size: 20px; line-height: 1; cursor: pointer; box-shadow: 0 6px 16px rgba(0, 0, 0, .12);
  transition: background .2s, color .2s;
}
.cf-arrow:hover { background: var(--navy-900); color: var(--white); }
.cf-prev { left: 16px; }
.cf-next { right: 16px; }

.cf-dots { position: absolute; left: 0; right: 0; bottom: -14px; display: flex; justify-content: center; gap: 8px; }
.cf-dots button {
  width: 9px; height: 9px; padding: 0; border: 0; border-radius: 50%; background: #c9d3e0; cursor: pointer;
  transition: width .3s, background .3s;
}
.cf-dots button[aria-current="true"] { width: 26px; border-radius: 5px; background: var(--blue); }

/* ---------- Industries ---------- */
.industry-strip { display: flex; gap: 14px; height: 400px; }
.industry {
  position: relative; flex: 1 1 0; min-width: 0; padding: 0; border: 0; border-radius: 20px; overflow: hidden;
  color: var(--white); font-family: inherit; text-align: left; cursor: pointer;
  transition: flex-grow .6s cubic-bezier(.22, .8, .3, 1), box-shadow .4s;
}
.industry.is-active { flex-grow: 3.4; box-shadow: var(--shadow); cursor: default; }
.industry::after { content: ""; position: absolute; inset: 0; background: linear-gradient(to top, rgba(0, 0, 0, .75), rgba(0, 0, 0, .05) 65%); }
.industry-art { position: absolute; right: -20px; top: 20px; width: 170px; height: 170px; opacity: .22; }
.industry-art svg { width: 100%; height: 100%; fill: none; stroke: currentColor; stroke-width: 1; stroke-linecap: round; stroke-linejoin: round; }
.industry-text { position: absolute; z-index: 1; left: 18px; right: 18px; bottom: 58px; }
.industry-text h3 { font-size: 19px; line-height: 1.25; }
.industry-text p {
  font-size: 15px; line-height: 1.5; max-height: 0; opacity: 0; overflow: hidden;
  transition: max-height .5s, opacity .4s, margin .4s;
}
.industry.is-active .industry-text h3 { font-size: 24px; }
/* Collapsed panels are too narrow for horizontal titles, so run them bottom-to-top. */
@media (min-width: 901px) {
  .industry:not(.is-active) .industry-text h3 { writing-mode: vertical-rl; transform: rotate(180deg); white-space: nowrap; }
}
.industry.is-active .industry-text p { max-height: 120px; opacity: 1; margin-top: 8px; transition-delay: .2s; }
.industry-go {
  position: absolute; z-index: 1; left: 18px; bottom: 18px; width: 30px; height: 30px;
  display: grid; place-items: center; border: 1.5px solid var(--white); border-radius: 50%; font-size: 15px;
}

/* ---------- Contact ---------- */
.contact-form {
  display: grid; grid-template-columns: 1fr 1fr; gap: 18px 20px; max-width: 760px; margin-inline: auto;
  padding: clamp(22px, 4vw, 40px); background: var(--white); border: 1px solid var(--line);
  border-radius: var(--radius-lg); box-shadow: var(--shadow);
}
.field { display: flex; flex-direction: column; gap: 6px; }
.field-full { grid-column: 1 / -1; }
.field label { font-weight: 700; color: var(--ink); font-size: 15px; }
.field input, .field textarea {
  width: 100%; padding: 12px 14px; font: inherit; color: var(--ink);
  border: 1px solid #cfd8e3; border-radius: 10px; background: var(--white); resize: vertical;
  transition: border-color .2s, box-shadow .2s;
}
.field input:focus, .field textarea:focus { outline: none; border-color: var(--blue); box-shadow: 0 0 0 3px rgba(37, 99, 235, .18); }
.field.is-invalid input, .field.is-invalid textarea { border-color: var(--red); }
.field__error { font-size: 13px; color: var(--red); }
.form-footer { display: flex; align-items: center; flex-wrap: wrap; gap: 16px; }
.form__status { font-size: 15px; font-weight: 600; }
.form__status.is-success { color: #14794a; }
.form__status.is-error { color: var(--red); }

/* ---------- Footer ---------- */
.footer { background: var(--gradient-navy); color: var(--white); padding-top: 56px; font-size: 15px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr; gap: 40px; padding-bottom: 40px; }
.footer-about p { margin-top: 14px; max-width: 520px; color: rgba(255, 255, 255, .85); text-align: justify; }
.footer-about .footer-slogan { font-size: 17px; font-weight: 600; color: var(--white); }
.footer h5 { position: relative; font-size: 19px; margin-bottom: 20px; }
.footer h5::after { content: ""; position: absolute; left: 0; bottom: -7px; width: 34px; height: 2px; background: #5aa9e6; }
.footer li { margin-bottom: 8px; }
.footer a:not(.brand) { color: rgba(255, 255, 255, .85); transition: color .2s, padding-left .2s; }
.footer a:not(.brand):hover { color: var(--white); padding-left: 4px; }
.footer-bottom { border-top: 1px solid rgba(255, 255, 255, .15); padding: 20px 0; text-align: center; font-size: 14px; }

/* ---------- Scroll reveal ---------- */
.js .reveal { opacity: 0; transform: translateY(28px); transition: opacity .7s ease, transform .7s ease; }
.js .reveal.in-view { opacity: 1; transform: none; }

/* ---------- Responsive ---------- */
@media (max-width: 900px) {
  .nav-toggle { display: block; }
  .nav-links {
    position: fixed; top: 0; right: 0; bottom: 0; z-index: 2005; width: min(320px, 82vw);
    padding: calc(var(--nav-h) + 20px) 28px 28px; background: var(--gradient-navy);
    transform: translateX(100%); visibility: hidden; transition: transform .35s ease, visibility .35s;
  }
  .nav-links ul { flex-direction: column; align-items: stretch; gap: 4px; }
  .nav-links a { display: block; padding: 14px 0; font-size: 18px; border-bottom: 1px solid rgba(255, 255, 255, .12); }
  .nav-links a::after { display: none; }
  .nav-links .nav-cta { margin-top: 18px; text-align: center; border-bottom: 1px solid rgba(255, 255, 255, .5); }
  body.nav-open { overflow: hidden; }
  body.nav-open .nav-links { transform: none; visibility: visible; }
  body.nav-open .nav-backdrop { opacity: 1; visibility: visible; }
  body.nav-open .navbar { transform: none; }

  .card-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-about { grid-column: 1 / -1; }

  .industry-strip { flex-direction: column; height: auto; }
  .industry { flex: none; height: 76px; transition: height .5s cubic-bezier(.22, .8, .3, 1); }
  .industry.is-active { height: 240px; }
  .industry-text { bottom: 22px; left: 62px; }
  .industry.is-active .industry-text { left: 18px; bottom: 58px; }
  .industry-go { bottom: 22px; }
}

@media (max-width: 600px) {
  body { font-size: 16px; }
  .container { width: calc(100% - 32px); }
  .contact-form { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 30px; }
  .coverflow { height: 460px; }
  .cf-card { width: 270px; margin-left: -135px; }
  .cf-arrow { top: auto; bottom: -32px; margin: 0; }
  .cf-prev { left: 16px; }
  .cf-next { right: 16px; }
  .about-overview p, .footer-about p { text-align: left; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition-duration: .01ms !important; }
  .js .reveal { opacity: 1; transform: none; }
}