/*
 * BTL Labs - styles.css
 * Version: 1.0.0
 * Last Updated: 2026-03-09
 * Industrial Luxury aesthetic for Bar Tech Labs Limited
 */

/* ─── Custom Properties ─── */
:root {
  --navy: #1B2A4A;
  --navy-deep: #111D35;
  --navy-light: #2D3E5F;
  --copper: #B87333;
  --copper-light: #D4944D;
  --copper-dark: #8F5A28;
  --copper-glow: rgba(184, 115, 51, 0.25);
  --text-body: #2C3E50;
  --text-muted: #5A6A7A;
  --bg: #F8F9FA;
  --surface: #FFFFFF;
  --warm: #FDF8F5;
  --warm-accent: #FBF0E8;

  --font-display: -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
  --font-body: -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
  --font-mono: "SF Mono", "Cascadia Code", "Fira Code", ui-monospace, monospace;

  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 1.5rem;
  --space-lg: 2.5rem;
  --space-xl: 4rem;
  --space-2xl: 6rem;
  --space-3xl: 8rem;

  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;

  --shadow-card: 0 1px 3px rgba(27, 42, 74, 0.06), 0 8px 24px rgba(27, 42, 74, 0.04);
  --shadow-card-hover: 0 4px 12px rgba(27, 42, 74, 0.08), 0 16px 40px rgba(27, 42, 74, 0.08);
  --shadow-copper: 0 4px 20px rgba(184, 115, 51, 0.3);

  --nav-height: 72px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--nav-height);
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.7;
  color: var(--text-body);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

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

a {
  text-decoration: none;
  color: inherit;
  transition: color var(--transition);
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

input,
select,
textarea {
  font-family: inherit;
  font-size: 1rem;
}

/* ─── Typography ─── */
h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.2;
  color: var(--navy);
  letter-spacing: -0.02em;
}

h1 { font-size: clamp(2rem, 5vw, 3.5rem); }
h2 { font-size: clamp(1.75rem, 4vw, 2.75rem); }
h3 { font-size: clamp(1.15rem, 2vw, 1.4rem); }

.section-label {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--copper);
  margin-bottom: var(--space-sm);
}

.section-label::before {
  content: "";
  display: block;
  width: 24px;
  height: 1px;
  background: var(--copper);
}

.section-heading {
  margin-bottom: var(--space-md);
}

.section-subtitle {
  font-size: 1.1rem;
  color: var(--text-muted);
  max-width: 540px;
  line-height: 1.7;
}

/* ─── Container ─── */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-md);
}

/* ─── Buttons ─── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.875rem 2rem;
  font-size: 0.9rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  border-radius: var(--radius-sm);
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
  white-space: nowrap;
}

.btn-copper {
  background: linear-gradient(135deg, var(--copper), var(--copper-light));
  color: #FFFFFF;
  box-shadow: var(--shadow-copper);
}

.btn-copper:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 28px rgba(184, 115, 51, 0.4);
  background: linear-gradient(135deg, var(--copper-light), var(--copper));
}

.btn-copper:active {
  transform: translateY(0);
}

.btn-outline {
  border: 1.5px solid rgba(255, 255, 255, 0.5);
  color: #FFFFFF;
  background: transparent;
}

.btn-outline:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: #FFFFFF;
  transform: translateY(-2px);
}

.btn-navy {
  background: var(--navy);
  color: #FFFFFF;
}

.btn-navy:hover {
  background: var(--navy-light);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(27, 42, 74, 0.3);
}

/* ─── Navigation ─── */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 0 var(--space-md);
  height: var(--nav-height);
  display: flex;
  align-items: center;
  transition: all var(--transition);
  background: transparent;
}

.navbar.scrolled {
  background: rgba(27, 42, 74, 0.97);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.05);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
}

.nav-logo img {
  height: 40px;
  width: auto;
}

.nav-links {
  display: none;
  list-style: none;
  gap: var(--space-lg);
  align-items: center;
}

.nav-links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: rgba(255, 255, 255, 0.75);
  letter-spacing: 0.02em;
  position: relative;
  padding: 0.25rem 0;
}

.nav-links a::after {
  content: "";
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 1.5px;
  background: var(--copper);
  transition: width var(--transition);
}

.nav-links a:hover,
.nav-links a.active {
  color: #FFFFFF;
}

.nav-links a:hover::after,
.nav-links a.active::after {
  width: 100%;
}

.nav-cta .btn {
  padding: 0.6rem 1.4rem;
  font-size: 0.8rem;
}

.nav-toggle {
  display: flex;
  flex-direction: column;
  gap: 5px;
  width: 28px;
  padding: 4px 0;
  background: none;
  border: none;
  cursor: pointer;
  z-index: 1001;
}

.nav-toggle span {
  display: block;
  height: 2px;
  background: #FFFFFF;
  border-radius: 2px;
  transition: all var(--transition);
  transform-origin: center;
}

.nav-toggle span:nth-child(1) { width: 100%; }
.nav-toggle span:nth-child(2) { width: 70%; }
.nav-toggle span:nth-child(3) { width: 85%; }

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

.nav-toggle.open span:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}

.nav-toggle.open span:nth-child(3) {
  width: 100%;
  transform: translateY(-7px) rotate(-45deg);
}

/* Mobile nav overlay */
.mobile-nav {
  position: fixed;
  inset: 0;
  z-index: 999;
  background: rgba(17, 29, 53, 0.98);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-lg);
  opacity: 0;
  visibility: hidden;
  transition: all 0.4s ease;
}

.mobile-nav.open {
  opacity: 1;
  visibility: visible;
}

.mobile-nav a {
  font-size: 1.5rem;
  font-weight: 600;
  color: rgba(255, 255, 255, 0.8);
  transition: all var(--transition);
  transform: translateY(20px);
  opacity: 0;
}

.mobile-nav.open a {
  transform: translateY(0);
  opacity: 1;
}

.mobile-nav.open a:nth-child(1) { transition-delay: 0.1s; }
.mobile-nav.open a:nth-child(2) { transition-delay: 0.15s; }
.mobile-nav.open a:nth-child(3) { transition-delay: 0.2s; }
.mobile-nav.open a:nth-child(4) { transition-delay: 0.25s; }
.mobile-nav.open a:nth-child(5) { transition-delay: 0.3s; }

.mobile-nav a:hover {
  color: var(--copper-light);
}

/* ─── Hero ─── */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: calc(var(--nav-height) + var(--space-xl)) var(--space-md) var(--space-xl);
  background: linear-gradient(160deg, var(--navy-deep) 0%, var(--navy) 40%, var(--navy-light) 100%);
  position: relative;
  overflow: hidden;
}

/* Geometric grid pattern overlay */
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    radial-gradient(circle at 1px 1px, rgba(184, 115, 51, 0.06) 1px, transparent 0);
  background-size: 48px 48px;
  pointer-events: none;
}

/* Diagonal copper accent line */
.hero::after {
  content: "";
  position: absolute;
  top: -20%;
  right: -10%;
  width: 1px;
  height: 140%;
  background: linear-gradient(to bottom, transparent, rgba(184, 115, 51, 0.15), transparent);
  transform: rotate(25deg);
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 720px;
}

.hero-logo {
  width: 200px;
  margin: 0 auto var(--space-lg);
}

.hero-logo img {
  width: 100%;
  display: block;
}

.hero h1 {
  color: #FFFFFF;
  margin-bottom: var(--space-sm);
  font-weight: 700;
}

.hero h1 .accent {
  background: linear-gradient(135deg, var(--copper-light), var(--copper));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  color: rgba(255, 255, 255, 0.65);
  font-size: clamp(1rem, 2vw, 1.15rem);
  line-height: 1.8;
  max-width: 560px;
  margin: 0 auto var(--space-lg);
}

.hero-ctas {
  display: flex;
  gap: var(--space-sm);
  justify-content: center;
  flex-wrap: wrap;
}

/* Hero load animations */
.hero-content > * {
  opacity: 0;
  transform: translateY(24px);
  animation: heroReveal 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.hero-content > *:nth-child(1) { animation-delay: 0.2s; }
.hero-content > *:nth-child(2) { animation-delay: 0.35s; }
.hero-content > *:nth-child(3) { animation-delay: 0.5s; }
.hero-content > *:nth-child(4) { animation-delay: 0.65s; }

@keyframes heroReveal {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ─── Sections Common ─── */
.section {
  padding: var(--space-2xl) 0;
}

.section-header {
  margin-bottom: var(--space-xl);
}

/* ─── Services ─── */
.services {
  background: var(--bg);
}

.card-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-md);
}

.card {
  background: var(--surface);
  border-radius: var(--radius-md);
  padding: var(--space-lg);
  box-shadow: var(--shadow-card);
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
  border: 1px solid rgba(27, 42, 74, 0.04);
}

.card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--copper), var(--copper-light));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition-slow);
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-card-hover);
}

.card:hover::before {
  transform: scaleX(1);
}

.card-icon {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-sm);
  background: linear-gradient(135deg, rgba(27, 42, 74, 0.06), rgba(27, 42, 74, 0.02));
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: var(--space-md);
  font-size: 1.5rem;
}

.card h3 {
  margin-bottom: 0.75rem;
}

.card p {
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.7;
}

.card-features {
  list-style: none;
  margin-top: var(--space-sm);
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.card-features li {
  font-size: 0.85rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.card-features li::before {
  content: "";
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--copper);
  flex-shrink: 0;
}

/* ─── Courses ─── */
.courses {
  background: var(--warm);
  position: relative;
}

.courses::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--warm-accent), transparent);
}

.course-card {
  background: var(--surface);
  border-radius: var(--radius-md);
  padding: var(--space-lg);
  box-shadow: var(--shadow-card);
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
  border: 1px solid rgba(184, 115, 51, 0.06);
}

.course-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-card-hover);
}

.course-badge {
  position: absolute;
  top: var(--space-md);
  right: var(--space-md);
  background: linear-gradient(135deg, var(--copper), var(--copper-light));
  color: #FFFFFF;
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 0.3rem 0.75rem;
  border-radius: 100px;
}

.course-card .card-icon {
  background: linear-gradient(135deg, rgba(184, 115, 51, 0.08), rgba(184, 115, 51, 0.02));
}

.course-card h3 {
  margin-bottom: 0.75rem;
  padding-right: 5rem;
}

.course-card p {
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.7;
}

/* Waitlist */
.waitlist {
  margin-top: var(--space-xl);
  text-align: center;
}

.waitlist p {
  font-size: 1rem;
  color: var(--text-body);
  margin-bottom: var(--space-sm);
  font-weight: 500;
}

.waitlist-form {
  display: flex;
  gap: 0.75rem;
  max-width: 440px;
  margin: 0 auto;
  flex-wrap: wrap;
  justify-content: center;
}

.waitlist-form input {
  flex: 1;
  min-width: 220px;
  padding: 0.875rem 1.25rem;
  border: 1.5px solid rgba(27, 42, 74, 0.12);
  border-radius: var(--radius-sm);
  background: var(--surface);
  font-size: 0.9rem;
  color: var(--text-body);
  transition: border-color var(--transition);
}

.waitlist-form input:focus {
  outline: none;
  border-color: var(--copper);
  box-shadow: 0 0 0 3px var(--copper-glow);
}

.waitlist-form .btn {
  padding: 0.875rem 1.5rem;
}

/* ─── About ─── */
.about {
  background: linear-gradient(160deg, var(--navy) 0%, var(--navy-deep) 100%);
  position: relative;
  overflow: hidden;
}

.about::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    radial-gradient(circle at 1px 1px, rgba(184, 115, 51, 0.04) 1px, transparent 0);
  background-size: 40px 40px;
  pointer-events: none;
}

.about-content {
  position: relative;
  z-index: 1;
}

.about .section-label {
  color: var(--copper-light);
}

.about .section-label::before {
  background: var(--copper-light);
}

.about .section-heading {
  color: #FFFFFF;
}

.about-text {
  color: rgba(255, 255, 255, 0.7);
  font-size: 1.1rem;
  line-height: 1.8;
  max-width: 640px;
  margin-bottom: var(--space-xl);
}

.values-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-md);
}

.value-item {
  padding: var(--space-md);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.03);
  transition: all var(--transition);
}

.value-item:hover {
  background: rgba(255, 255, 255, 0.06);
  border-color: rgba(184, 115, 51, 0.2);
}

.value-icon {
  font-size: 1.5rem;
  margin-bottom: 0.75rem;
}

.value-item h3 {
  color: #FFFFFF;
  font-size: 1.1rem;
  margin-bottom: 0.5rem;
}

.value-item p {
  color: rgba(255, 255, 255, 0.55);
  font-size: 0.9rem;
  line-height: 1.7;
}

/* ─── Contact ─── */
.contact {
  background: var(--bg);
}

.contact-wrapper {
  max-width: 640px;
}

.contact-form {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.form-group label {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--navy);
  letter-spacing: 0.02em;
}

.form-group input,
.form-group select,
.form-group textarea {
  padding: 0.875rem 1.25rem;
  border: 1.5px solid rgba(27, 42, 74, 0.12);
  border-radius: var(--radius-sm);
  background: var(--surface);
  color: var(--text-body);
  transition: all var(--transition);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--copper);
  box-shadow: 0 0 0 3px var(--copper-glow);
}

.form-group input.error,
.form-group select.error,
.form-group textarea.error {
  border-color: #E74C3C;
  box-shadow: 0 0 0 3px rgba(231, 76, 60, 0.15);
}

.form-group .error-msg {
  font-size: 0.78rem;
  color: #E74C3C;
  display: none;
}

.form-group .error-msg.visible {
  display: block;
}

.form-group textarea {
  resize: vertical;
  min-height: 140px;
}

.form-group select {
  appearance: none;
  -webkit-appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%232C3E50' fill='none' stroke-width='1.5' stroke-linecap='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 1.25rem center;
  padding-right: 3rem;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-md);
}

.contact-form .btn {
  align-self: flex-start;
  padding: 1rem 2.5rem;
}

/* Success toast */
.toast {
  position: fixed;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%) translateY(120%);
  background: var(--navy);
  color: #FFFFFF;
  padding: 1rem 2rem;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  font-weight: 500;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
  z-index: 2000;
  opacity: 0;
  transition: all 0.4s cubic-bezier(0.16, 1, 0.3, 1);
  display: flex;
  align-items: center;
  gap: 0.5rem;
  white-space: nowrap;
}

.toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.toast .toast-icon {
  color: var(--copper-light);
}

/* ─── Footer ─── */
.footer {
  background: var(--navy-deep);
  padding: var(--space-xl) 0 var(--space-lg);
  border-top: 1px solid rgba(255, 255, 255, 0.04);
}

.footer-inner {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}

.footer-top {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
  align-items: flex-start;
}

.footer-logo img {
  height: 64px;
  filter: brightness(1.35) contrast(1.1);
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-md);
  list-style: none;
}

.footer-links a {
  font-size: 0.875rem;
  color: rgba(255, 255, 255, 0.5);
  transition: color var(--transition);
}

.footer-links a:hover {
  color: var(--copper-light);
}

.footer-divider {
  width: 100%;
  height: 1px;
  background: rgba(255, 255, 255, 0.06);
}

.footer-bottom {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  font-size: 0.8rem;
  color: rgba(255, 255, 255, 0.35);
}

.footer-bottom a {
  color: rgba(255, 255, 255, 0.45);
}

.footer-bottom a:hover {
  color: var(--copper-light);
}

/* ─── Scroll Reveal ─── */
.reveal {
  opacity: 0;
  transform: translateY(32px);
  transition: opacity 0.7s cubic-bezier(0.16, 1, 0.3, 1),
              transform 0.7s cubic-bezier(0.16, 1, 0.3, 1);
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

.reveal-delay-1 { transition-delay: 0.1s; }
.reveal-delay-2 { transition-delay: 0.2s; }
.reveal-delay-3 { transition-delay: 0.3s; }

/* ─── Responsive: Tablet (768px+) ─── */
@media (min-width: 768px) {
  .card-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .values-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .form-row {
    grid-template-columns: 1fr 1fr;
  }

  .hero-logo {
    width: 240px;
  }

  .footer-top {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
  }

  .footer-bottom {
    flex-direction: row;
    justify-content: space-between;
  }
}

/* ─── Responsive: Desktop (1024px+) ─── */
@media (min-width: 1024px) {
  :root {
    --nav-height: 80px;
  }

  .nav-links {
    display: flex;
  }

  .nav-toggle {
    display: none;
  }

  .section {
    padding: var(--space-3xl) 0;
  }

  .card-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-lg);
  }

  .hero-logo {
    width: 260px;
  }

  .hero-subtitle {
    font-size: 1.15rem;
  }
}