/* ==========================================================================
   LFT Lighting — style.css
   High-end, minimal, photography-driven design (brand: #004EA2 / #6EBA2C)
   ========================================================================== */

/* ---------- Design tokens ---------- */
:root {
  --blue:        #004EA2;
  --blue-deep:   #003C7D;
  --blue-ink:    #0A1B33;   /* near-black navy for dark sections */
  --green:       #6EBA2C;
  --green-dark:  #5AA322;
  --white:       #FFFFFF;
  --bg:          #FFFFFF;
  --bg-soft:     #F4F6F9;
  --ink:         #14202E;
  --gray:        #5B6675;
  --gray-light:  #8B95A3;
  --line:        #E3E8EF;
  --font-sans: "Helvetica Neue", Helvetica, Arial, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  --container: 1240px;
  --gutter:    clamp(20px, 4vw, 48px);
  --radius:    2px;
  --shadow-1:  0 6px 24px rgba(10, 27, 51, .08);
  --shadow-2:  0 18px 48px rgba(10, 27, 51, .16);
  --ease:      cubic-bezier(.22, .61, .36, 1);
}

/* ---------- Reset / base ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.7;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
img { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }
em { font-style: normal; }

.container { max-width: var(--container); margin-inline: auto; padding-inline: var(--gutter); }
.section { padding-block: clamp(80px, 10vw, 140px); }
.section-light { background: var(--bg-soft); }
.section-dark  { background: var(--blue-ink); color: #E8EDF4; }

/* Section headings */
.section-eyebrow {
  display: inline-flex; align-items: center; gap: 12px;
  font-size: 13px; font-weight: 600; letter-spacing: .22em;
  text-transform: uppercase; color: var(--blue);
  margin-bottom: 22px;
}
.section-eyebrow::before { content: ""; width: 34px; height: 2px; background: var(--green); }
.section-dark .section-eyebrow { color: #9FC4EF; }
.section-title {
  font-size: clamp(30px, 4.4vw, 52px);
  line-height: 1.12; font-weight: 700; letter-spacing: -0.015em;
  margin-bottom: 26px;
}
.section-title em { color: var(--blue); font-style: italic; font-family: Georgia, "Times New Roman", serif; font-weight: 600; }
.section-dark .section-title em { color: var(--green); }
.section-lead { color: var(--gray); max-width: 380px; font-size: 16px; }
.section-dark .section-lead { color: #A9B6C7; }
.section-head {
  display: flex; justify-content: space-between; align-items: flex-end;
  gap: 40px; margin-bottom: clamp(44px, 6vw, 72px);
}
@media (max-width: 860px) { .section-head { flex-direction: column; align-items: flex-start; } }

/* Buttons */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 10px;
  padding: 15px 34px; border: 1px solid transparent; border-radius: var(--radius);
  font-size: 14px; font-weight: 600; letter-spacing: .12em; text-transform: uppercase;
  cursor: pointer; transition: all .3s var(--ease); white-space: nowrap;
}
.btn-primary { background: var(--blue); color: #fff; }
.btn-primary:hover { background: var(--blue-deep); transform: translateY(-2px); box-shadow: var(--shadow-1); }
.btn-ghost { border-color: rgba(255,255,255,.55); color: #fff; }
.btn-ghost:hover { background: rgba(255,255,255,.12); border-color: #fff; }
.btn-dark { background: var(--blue-ink); color: #fff; }
.btn-dark:hover { background: var(--blue); transform: translateY(-2px); }
.btn-green { background: var(--green); color: #fff; }
.btn-green:hover { background: var(--green-dark); transform: translateY(-2px); box-shadow: var(--shadow-1); }
.btn-full { width: 100%; }
:focus-visible { outline: 2px solid var(--green); outline-offset: 3px; }

/* Reveal on scroll */
.reveal { opacity: 0; transform: translateY(28px); transition: opacity .8s var(--ease), transform .8s var(--ease); }
.reveal.visible { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
}

/* ==========================================================================
   Header
   ========================================================================== */
.site-header {
  position: fixed; inset: 0 0 auto 0; z-index: 100;
  padding-block: 18px;
  transition: background .35s var(--ease), box-shadow .35s var(--ease), padding .35s var(--ease);
}
.site-header.scrolled {
  background: rgba(8, 20, 38, .92);
  backdrop-filter: blur(12px);
  padding-block: 10px;
  box-shadow: 0 4px 24px rgba(0,0,0,.25);
}
.header-inner { display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.brand { display: flex; align-items: center; gap: 13px; }
.brand img { width: 46px; height: 46px; filter: drop-shadow(0 2px 6px rgba(0,0,0,.35)); }
.brand-text { display: flex; flex-direction: column; line-height: 1.25; color: #fff; }
.brand-text strong { font-size: 16px; letter-spacing: .18em; }
.brand-text em { font-size: 11px; color: rgba(255,255,255,.66); letter-spacing: .04em; }
.main-nav { display: flex; align-items: center; gap: 34px; }
.main-nav a {
  color: rgba(255,255,255,.85); font-size: 14px; font-weight: 500; letter-spacing: .06em;
  position: relative; padding-block: 6px; transition: color .25s;
}
.main-nav a::after {
  content: ""; position: absolute; left: 0; bottom: 0; width: 0; height: 2px;
  background: var(--green); transition: width .3s var(--ease);
}
.main-nav a:hover { color: #fff; }
.main-nav a:hover::after { width: 100%; }
.main-nav .nav-cta {
  border: 1px solid var(--green); color: #fff; padding: 9px 22px;
}
.main-nav .nav-cta::after { display: none; }
.main-nav .nav-cta:hover { background: var(--green); }
.nav-toggle { display: none; }

@media (max-width: 920px) {
  .brand-text em { display: none; }
  .nav-toggle {
    display: flex; flex-direction: column; gap: 6px; justify-content: center;
    width: 44px; height: 44px; background: none; border: 0; cursor: pointer; z-index: 110;
  }
  .nav-toggle span { width: 26px; height: 2px; background: #fff; transition: all .3s var(--ease); }
  .nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(8px) rotate(45deg); }
  .nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
  .nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-8px) rotate(-45deg); }
  .main-nav {
    position: fixed; inset: 0; flex-direction: column; justify-content: center; gap: 8px;
    background: rgba(8, 20, 38, .97); backdrop-filter: blur(10px);
    transform: translateY(-100%); transition: transform .45s var(--ease);
  }
  .main-nav.open { transform: none; }
  .main-nav a { font-size: 22px; padding: 12px; }
}

/* ==========================================================================
   Hero
   ========================================================================== */
.hero {
  position: relative; min-height: 100svh;
  display: flex; align-items: center;
  color: #fff; overflow: hidden;
}
.hero-bg {
  position: absolute; inset: 0;
  background: url("../img/hero.jpg") center 30% / cover no-repeat;
  animation: heroZoom 14s var(--ease) forwards;
}
@keyframes heroZoom { from { transform: scale(1.08); } to { transform: scale(1); } }
.hero-overlay {
  position: absolute; inset: 0;
  background:
    linear-gradient(105deg, rgba(6,16,32,.88) 0%, rgba(6,16,32,.55) 46%, rgba(6,16,32,.18) 100%),
    linear-gradient(to top, rgba(6,16,32,.75), transparent 34%);
}
.hero-content { position: relative; z-index: 2; padding-top: 60px; }
.hero-eyebrow {
  font-size: 13px; letter-spacing: .3em; text-transform: uppercase;
  color: var(--green); margin-bottom: 26px; font-weight: 600;
}
.hero-title { font-size: clamp(46px, 8.4vw, 104px); line-height: 1.04; font-weight: 700; letter-spacing: -0.02em; }
.hero-title .line { display: block; }
.hero-title em {
  color: var(--green); font-style: italic;
  font-family: Georgia, "Times New Roman", serif; font-weight: 600;
}
.hero-sub { max-width: 560px; margin-top: 30px; font-size: clamp(16px, 1.6vw, 19px); color: rgba(255,255,255,.82); }
.hero-actions { display: flex; gap: 18px; margin-top: 44px; flex-wrap: wrap; }

.scroll-hint {
  position: absolute; left: 50%; bottom: 34px; transform: translateX(-50%);
  display: flex; flex-direction: column; align-items: center; gap: 10px; z-index: 2;
}
.scroll-text { font-size: 11px; letter-spacing: .3em; text-transform: uppercase; color: rgba(255,255,255,.7); }
.scroll-line { width: 1px; height: 52px; background: rgba(255,255,255,.35); position: relative; overflow: hidden; }
.scroll-line::after {
  content: ""; position: absolute; inset: 0; background: #fff;
  animation: scrollDrop 2.2s var(--ease) infinite;
}
@keyframes scrollDrop { 0% { transform: translateY(-100%); } 55% { transform: translateY(0); } 100% { transform: translateY(100%); } }

/* ==========================================================================
   Stats
   ========================================================================== */
.stats { background: var(--blue); color: #fff; }
.stats-grid {
  display: grid; grid-template-columns: repeat(4, 1fr);
  padding-block: 34px; gap: 24px;
}
.stat { text-align: center; padding-inline: 12px; }
.stat + .stat { border-left: 1px solid rgba(255,255,255,.22); }
.stat-num { display: block; font-size: clamp(30px, 3.6vw, 44px); font-weight: 700; line-height: 1.15; }
.stat-label { font-size: 13px; letter-spacing: .08em; color: rgba(255,255,255,.78); text-transform: uppercase; }
@media (max-width: 760px) {
  .stats-grid { grid-template-columns: repeat(2, 1fr); row-gap: 30px; }
  .stat:nth-child(3) { border-left: 0; }
}

/* ==========================================================================
   About
   ========================================================================== */
.about-grid {
  display: grid; grid-template-columns: minmax(0, 46%) minmax(0, 1fr);
  gap: clamp(40px, 6vw, 90px); align-items: center;
}
.about-media { position: relative; padding-bottom: 64px; }
.about-img { overflow: hidden; box-shadow: var(--shadow-2); }
.about-img.main { width: 82%; }
.about-img img { transition: transform 1.2s var(--ease); width: 100%; }
.about-img:hover img { transform: scale(1.05); }
.about-img.secondary {
  position: absolute; right: 0; bottom: 0; width: 46%;
  border: 8px solid var(--bg);
}
.about-badge {
  position: absolute; top: -26px; right: 6%;
  background: var(--green); color: #fff;
  display: flex; align-items: center; gap: 12px;
  padding: 18px 22px; box-shadow: var(--shadow-1);
}
.about-badge .num { font-size: 40px; font-weight: 700; line-height: 1; }
.about-badge .txt { font-size: 12px; line-height: 1.4; text-transform: uppercase; letter-spacing: .08em; }
.about-copy p { color: var(--gray); margin-bottom: 20px; max-width: 60ch; }
.about-copy .btn { margin-top: 10px; }
@media (max-width: 920px) {
  .about-grid { grid-template-columns: 1fr; }
  .about-media { max-width: 560px; }
}

/* ==========================================================================
   Expertise
   ========================================================================== */
.expertise-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px;
}
.exp-card {
  border: 1px solid rgba(255,255,255,.14);
  padding: 40px 30px 36px; border-radius: var(--radius);
  transition: transform .4s var(--ease), border-color .4s, background .4s;
  position: relative;
}
.exp-card:hover { transform: translateY(-8px); border-color: var(--green); background: rgba(255,255,255,.04); }
.exp-num {
  font-size: 15px; font-weight: 700; color: var(--green);
  letter-spacing: .1em; display: block; margin-bottom: 70px;
}
.exp-card h3 { font-size: 20px; font-weight: 600; margin-bottom: 14px; color: #fff; line-height: 1.35; }
.exp-card p { font-size: 15px; color: #A9B6C7; }
@media (max-width: 1080px) { .expertise-grid { grid-template-columns: repeat(2, 1fr); } .exp-num { margin-bottom: 34px; } }
@media (max-width: 560px)  { .expertise-grid { grid-template-columns: 1fr; } }

/* ==========================================================================
   Applications
   ========================================================================== */
.app-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.app-tile { position: relative; overflow: hidden; display: block; aspect-ratio: 3 / 4; }
.app-tile img { width: 100%; height: 100%; object-fit: cover; transition: transform 1.1s var(--ease); }
.app-tile:hover img { transform: scale(1.07); }
.app-tile::after {
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(to top, rgba(6,16,32,.82), transparent 52%);
  transition: opacity .4s;
}
.app-label {
  position: absolute; left: 26px; right: 26px; bottom: 24px; z-index: 2;
  color: #fff; display: flex; flex-direction: column; gap: 4px;
  transform: translateY(8px); transition: transform .45s var(--ease);
}
.app-tile:hover .app-label { transform: none; }
.app-label strong { font-size: 20px; font-weight: 600; }
.app-label em { font-size: 13px; color: rgba(255,255,255,.75); letter-spacing: .04em; }
@media (max-width: 860px) { .app-grid { grid-template-columns: 1fr; } .app-tile { aspect-ratio: 4 / 3; } }

/* ==========================================================================
   Projects
   ========================================================================== */
/* Featured */
.featured-project {
  display: grid; grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr);
  gap: clamp(32px, 5vw, 70px); align-items: center;
  margin-bottom: clamp(56px, 7vw, 96px);
}
.featured-media {
  position: relative; display: grid;
  grid-template-columns: repeat(6, 1fr); gap: 14px;
}
.featured-media img { border-radius: var(--radius); box-shadow: var(--shadow-1); }
.featured-media .fm-1 { grid-column: 1 / 4; grid-row: 1 / 3; aspect-ratio: 3 / 4; object-fit: cover; height: 100%; }
.featured-media .fm-2 { grid-column: 4 / 7; grid-row: 1 / 2; aspect-ratio: 4 / 3; object-fit: cover; height: 100%; }
.featured-media .fm-3 { grid-column: 4 / 7; grid-row: 2 / 3; aspect-ratio: 4 / 3; object-fit: cover; height: 100%; }
.featured-copy .proj-tag {
  color: var(--green-dark); font-size: 13px; font-weight: 700;
  letter-spacing: .2em; text-transform: uppercase; margin-bottom: 16px;
}
.featured-copy h3 {
  font-size: clamp(26px, 3vw, 38px); line-height: 1.18; font-weight: 700; margin-bottom: 20px;
}
.featured-copy > p { color: var(--gray); margin-bottom: 28px; }
.proj-facts { border-top: 1px solid var(--line); }
.proj-facts li {
  display: flex; justify-content: space-between; gap: 20px;
  padding-block: 14px; border-bottom: 1px solid var(--line); font-size: 15px;
}
.proj-facts span { color: var(--gray-light); letter-spacing: .06em; text-transform: uppercase; font-size: 12.5px; }
.proj-facts em { font-weight: 600; }
@media (max-width: 920px) { .featured-project { grid-template-columns: 1fr; } }

/* Grid */
.proj-grid {
  display: grid; grid-template-columns: repeat(3, 1fr);
  grid-auto-rows: 300px; gap: 20px;
}
.proj-card { position: relative; overflow: hidden; border-radius: var(--radius); }
.proj-card.wide { grid-column: span 2; }
.proj-card img {
  width: 100%; height: 100%; object-fit: cover;
  transition: transform 1.1s var(--ease), filter .5s;
}
.proj-card:hover img { transform: scale(1.06); }
.proj-card figcaption {
  position: absolute; left: 0; right: 0; bottom: 0;
  padding: 44px 22px 18px;
  background: linear-gradient(to top, rgba(6,16,32,.85), transparent);
  color: #fff; display: flex; flex-direction: column;
  transform: translateY(10px); opacity: .95; transition: all .45s var(--ease);
}
.proj-card:hover figcaption { transform: none; opacity: 1; }
.proj-card figcaption strong { font-size: 17px; font-weight: 600; }
.proj-card figcaption span { font-size: 12.5px; color: rgba(255,255,255,.75); letter-spacing: .05em; }
@media (max-width: 920px) { .proj-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 600px) { .proj-grid { grid-template-columns: 1fr; grid-auto-rows: 260px; } .proj-card.wide { grid-column: span 1; } }

/* ==========================================================================
   CTA band
   ========================================================================== */
.cta { position: relative; overflow: hidden; color: #fff; }
.cta-bg {
  position: absolute; inset: 0;
  background: url("../img/cta-bg.jpg") center / cover no-repeat fixed;
}
.cta-overlay { position: absolute; inset: 0; background: linear-gradient(100deg, rgba(0,42,88,.94), rgba(0,60,125,.82)); }
.cta-inner {
  position: relative; z-index: 2;
  padding-block: clamp(90px, 12vw, 160px);
  display: flex; flex-direction: column; align-items: flex-start; gap: 22px;
}
.cta h2 { font-size: clamp(36px, 5.4vw, 64px); line-height: 1.1; font-weight: 700; letter-spacing: -0.015em; }
.cta h2 em { color: var(--green); font-style: italic; font-family: Georgia, serif; }
.cta p { max-width: 520px; color: rgba(255,255,255,.85); }

/* ==========================================================================
   Contact
   ========================================================================== */
.contact-grid {
  display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: clamp(44px, 6vw, 100px); align-items: start;
}
.contact-info > p { color: var(--gray); margin-bottom: 34px; max-width: 46ch; }
.contact-list { border-top: 1px solid var(--line); }
.contact-list li {
  display: grid; grid-template-columns: 110px 1fr; gap: 18px;
  padding-block: 18px; border-bottom: 1px solid var(--line);
}
.c-label { color: var(--gray-light); font-size: 12.5px; letter-spacing: .14em; text-transform: uppercase; padding-top: 3px; }
.c-value { font-weight: 500; }
.c-value a:hover { color: var(--blue); }

.contact-form {
  background: var(--bg-soft); padding: clamp(28px, 4vw, 46px);
  border-radius: var(--radius); box-shadow: var(--shadow-1);
}
.contact-form h3 { font-size: 22px; margin-bottom: 26px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
@media (max-width: 560px) { .form-row { grid-template-columns: 1fr; } }
.form-field { margin-bottom: 18px; }
.form-field label { display: block; font-size: 13px; font-weight: 600; letter-spacing: .06em; margin-bottom: 8px; color: var(--ink); }
.form-field label b { color: var(--green-dark); }
.form-field input, .form-field textarea {
  width: 100%; padding: 13px 16px; font: inherit; font-size: 15px;
  border: 1px solid var(--line); border-radius: var(--radius);
  background: #fff; color: var(--ink);
  transition: border-color .25s, box-shadow .25s;
}
.form-field input:focus, .form-field textarea:focus {
  outline: none; border-color: var(--blue);
  box-shadow: 0 0 0 3px rgba(0, 78, 162, .12);
}
.form-field textarea { resize: vertical; min-height: 120px; }
.form-field.invalid input, .form-field.invalid textarea { border-color: #D64545; }
.form-note { margin-top: 14px; font-size: 12.5px; color: var(--gray-light); text-align: center; }

/* ==========================================================================
   Footer
   ========================================================================== */
.site-footer { background: var(--blue-ink); color: #A9B6C7; }
.footer-grid {
  display: grid; grid-template-columns: minmax(0, 1.4fr) auto auto;
  gap: clamp(32px, 5vw, 80px); align-items: start;
  padding-block: clamp(48px, 6vw, 72px);
}
.footer-brand { display: flex; gap: 16px; }
.footer-brand img { width: 56px; height: 56px; }
.footer-brand strong { display: block; color: #fff; font-size: 15px; letter-spacing: .04em; margin-bottom: 8px; }
.footer-brand p { font-size: 14px; max-width: 40ch; }
.footer-nav { display: flex; flex-direction: column; gap: 10px; }
.footer-nav a { font-size: 14.5px; transition: color .25s; }
.footer-nav a:hover { color: #fff; }
.footer-contact { display: flex; flex-direction: column; gap: 10px; font-size: 14.5px; }
.footer-contact a:hover { color: #fff; }
.footer-bottom {
  display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap;
  padding-block: 22px; border-top: 1px solid rgba(255,255,255,.1);
  font-size: 13px; color: #7385A0;
}
@media (max-width: 860px) { .footer-grid { grid-template-columns: 1fr; } }