/* =========================================================
   Space Frontiers Pakistan — National Commercial Space Conference
   Stylesheet (Activity 3 implementation of Activity 2 design)
   ========================================================= */

:root {
  --navy:   #0B1E3F;
  --cosmic: #1F3A68;
  --orange: #D9822B;
  --orange-dark: #B86A1F;
  --white:  #F4F7FB;
  --slate:  #4A4A4A;
  --slate-soft: #6B6B6B;
  --line:   #DDE4EE;
  --shadow: 0 6px 24px rgba(11, 30, 63, 0.08);
  --radius: 8px;
  --container: 1140px;
  --display: 'Space Grotesk', system-ui, -apple-system, sans-serif;
  --body: 'Inter', system-ui, -apple-system, sans-serif;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--body);
  font-size: 16px;
  line-height: 1.6;
  color: var(--slate);
  background: var(--white);
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5 {
  font-family: var(--display);
  color: var(--navy);
  font-weight: 700;
  line-height: 1.25;
  margin: 0 0 1rem;
}
h1 { font-size: clamp(2rem, 5vw, 3rem); }
h2 { font-size: clamp(1.5rem, 3vw, 2rem); }
h3 { font-size: 1.25rem; }

p { margin: 0 0 1rem; }
a { color: var(--cosmic); text-decoration: none; }
a:hover, a:focus { color: var(--orange); text-decoration: underline; }

/* ---- Skip link ---- */
.skip-link {
  position: absolute;
  top: -40px;
  left: 8px;
  background: var(--orange);
  color: #fff;
  padding: 8px 14px;
  border-radius: 4px;
  z-index: 1000;
  font-weight: 600;
}
.skip-link:focus { top: 8px; color: #fff; text-decoration: none; }

/* ---- Author credit ribbon (top of page, above sticky header) ---- */
.credit-bar {
  background: #061528;
  color: rgba(255,255,255,0.78);
  font-size: 0.78rem;
  font-family: var(--body);
  letter-spacing: 0.05em;
}
.credit-bar-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 6px 20px;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px;
}
.credit-bar-inner strong { color: #fff; font-weight: 600; }
@media (max-width: 540px) {
  .credit-bar-inner { justify-content: center; text-align: center; }
}

.footer-credit {
  flex-basis: 100%;
  width: 100%;
  text-align: center;
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid rgba(255,255,255,0.08);
  color: rgba(255,255,255,0.85);
  font-size: 0.92rem;
  letter-spacing: 0.04em;
}
.footer-credit strong { color: #fff; font-weight: 600; }

/* ---- Header ---- */
.site-header {
  background: var(--navy);
  color: #fff;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow);
}
.nav-wrap {
  max-width: var(--container);
  margin: 0 auto;
  padding: 14px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: #fff;
  font-family: var(--display);
  font-weight: 700;
  font-size: 1.1rem;
}
.brand:hover { color: #fff; text-decoration: none; }
.brand-mark {
  width: 36px;
  height: 36px;
  display: inline-block;
}
.brand-text { line-height: 1.1; }
.brand-text small {
  display: block;
  font-size: 0.7rem;
  font-weight: 400;
  color: rgba(255,255,255,0.7);
  font-family: var(--body);
}

.nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid rgba(255,255,255,0.4);
  color: #fff;
  padding: 6px 10px;
  border-radius: 4px;
  cursor: pointer;
}

.nav-list {
  list-style: none;
  display: flex;
  gap: 6px;
  margin: 0;
  padding: 0;
}
.nav-list a {
  color: #fff;
  padding: 8px 12px;
  border-radius: 4px;
  font-weight: 500;
  font-size: 0.95rem;
}
.nav-list a:hover, .nav-list a:focus {
  background: rgba(255,255,255,0.1);
  color: #fff;
  text-decoration: none;
}
.nav-list a.active {
  background: var(--orange);
  color: #fff;
}
.nav-list a.cta {
  background: var(--orange);
  color: #fff;
  margin-left: 6px;
}
.nav-list a.cta:hover { background: var(--orange-dark); }

@media (max-width: 860px) {
  .nav-toggle { display: inline-block; }
  .nav-list {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--navy);
    flex-direction: column;
    gap: 0;
    padding: 8px 0;
    border-top: 1px solid rgba(255,255,255,0.1);
  }
  .nav-list.open { display: flex; }
  .nav-list a {
    display: block;
    padding: 12px 20px;
    border-radius: 0;
    margin: 0;
  }
}

/* ---- Hero ---- */
.hero {
  background: linear-gradient(135deg, var(--navy) 0%, var(--cosmic) 100%);
  color: #fff;
  padding: 80px 20px 100px;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    radial-gradient(2px 2px at 20% 30%, rgba(255,255,255,0.4), transparent),
    radial-gradient(1px 1px at 70% 50%, rgba(255,255,255,0.5), transparent),
    radial-gradient(1.5px 1.5px at 40% 80%, rgba(255,255,255,0.3), transparent),
    radial-gradient(2px 2px at 85% 20%, rgba(255,255,255,0.4), transparent),
    radial-gradient(1px 1px at 10% 70%, rgba(255,255,255,0.5), transparent);
  opacity: 0.6;
  pointer-events: none;
}
.hero-inner {
  max-width: var(--container);
  margin: 0 auto;
  position: relative;
  z-index: 1;
}
.hero h1 { color: #fff; margin-bottom: 1rem; }
.hero .lead {
  font-size: 1.15rem;
  color: rgba(255,255,255,0.9);
  margin-bottom: 1.5rem;
  max-width: 720px;
}
.hero .meta {
  display: flex;
  flex-wrap: wrap;
  gap: 24px;
  margin-bottom: 2rem;
  font-size: 0.95rem;
  color: rgba(255,255,255,0.85);
}
.hero .meta strong { color: #fff; display: block; font-size: 1.05rem; }
.hero .meta-item { display: flex; gap: 12px; }
.hero .meta-icon {
  font-size: 1.4rem;
  opacity: 0.8;
}

/* ---- Page header (non-hero pages) ---- */
.page-header {
  background: var(--navy);
  color: #fff;
  padding: 50px 20px 60px;
}
.page-header-inner {
  max-width: var(--container);
  margin: 0 auto;
}
.page-header h1 { color: #fff; margin-bottom: 0.5rem; }
.page-header p { color: rgba(255,255,255,0.85); margin: 0; }

/* ---- Buttons ---- */
.btn {
  display: inline-block;
  padding: 12px 22px;
  border-radius: 6px;
  font-weight: 600;
  font-family: var(--body);
  font-size: 1rem;
  border: 2px solid transparent;
  cursor: pointer;
  text-align: center;
  transition: background 0.15s, color 0.15s, border-color 0.15s;
}
.btn:focus { outline: 3px solid rgba(217, 130, 43, 0.5); outline-offset: 2px; }
.btn-primary {
  background: var(--orange);
  color: #fff;
}
.btn-primary:hover, .btn-primary:focus {
  background: var(--orange-dark);
  color: #fff;
  text-decoration: none;
}
.btn-secondary {
  background: var(--cosmic);
  color: #fff;
}
.btn-secondary:hover, .btn-secondary:focus {
  background: var(--navy);
  color: #fff;
  text-decoration: none;
}
.btn-ghost {
  background: transparent;
  color: #fff;
  border-color: #fff;
}
.btn-ghost:hover, .btn-ghost:focus {
  background: #fff;
  color: var(--navy);
  text-decoration: none;
}
.btn-outline {
  background: transparent;
  color: var(--cosmic);
  border-color: var(--cosmic);
}
.btn-outline:hover, .btn-outline:focus {
  background: var(--cosmic);
  color: #fff;
  text-decoration: none;
}
.btn-block { display: block; width: 100%; }

/* ---- Sections ---- */
.section {
  padding: 70px 20px;
}
.section-narrow {
  padding: 50px 20px;
}
.section-light { background: #fff; }
.section-tinted { background: var(--white); }
.section-dark { background: var(--navy); color: #fff; }
.section-dark h2, .section-dark h3 { color: #fff; }
.section-inner {
  max-width: var(--container);
  margin: 0 auto;
}
.section-title {
  text-align: center;
  margin-bottom: 12px;
}
.section-sub {
  text-align: center;
  color: var(--slate-soft);
  max-width: 720px;
  margin: 0 auto 40px;
}

/* ---- Value props ---- */
.value-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 30px;
}
@media (max-width: 768px) { .value-row { grid-template-columns: 1fr; } }
.value-card {
  background: #fff;
  padding: 28px;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  text-align: center;
}
.value-card .num {
  font-family: var(--display);
  font-size: 2.4rem;
  font-weight: 700;
  color: var(--orange);
  display: block;
}
.value-card h3 { margin-top: 8px; }

/* ---- Partner strip ---- */
.partners {
  display: flex;
  flex-wrap: wrap;
  gap: 30px;
  justify-content: center;
  align-items: center;
  margin-top: 24px;
}
.partner {
  background: #fff;
  border: 1px solid var(--line);
  padding: 18px 26px;
  border-radius: var(--radius);
  font-family: var(--display);
  font-weight: 500;
  color: var(--cosmic);
  font-size: 0.95rem;
}

/* ---- Cards (general) ---- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 30px;
}
@media (max-width: 1024px) { .card-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 600px)  { .card-grid { grid-template-columns: 1fr; } }
.card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px;
  transition: transform 0.15s, box-shadow 0.15s;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.card h3 { margin-bottom: 6px; font-size: 1.15rem; }
.card .role { color: var(--slate-soft); font-size: 0.9rem; margin-bottom: 12px; }

/* ---- Speaker card ---- */
.speaker-photo {
  width: 100%;
  aspect-ratio: 1 / 1;
  border-radius: 6px;
  background: linear-gradient(135deg, var(--cosmic), var(--orange));
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--display);
  font-size: 2.5rem;
  color: #fff;
  font-weight: 700;
  margin-bottom: 14px;
}
.speaker-bio { font-size: 0.92rem; color: var(--slate); margin-bottom: 12px; }
.speaker-bio.expanded { max-height: none; }
.speaker-bio:not(.expanded) {
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.bio-toggle {
  background: transparent;
  border: none;
  color: var(--cosmic);
  font-weight: 600;
  padding: 0;
  cursor: pointer;
  font-size: 0.9rem;
}
.bio-toggle:hover { color: var(--orange); text-decoration: underline; }

/* ---- Agenda ---- */
.day-tabs {
  display: flex;
  gap: 6px;
  margin-bottom: 16px;
  border-bottom: 2px solid var(--line);
}
.day-tab {
  background: transparent;
  border: none;
  padding: 12px 22px;
  font-family: var(--display);
  font-weight: 600;
  color: var(--slate-soft);
  cursor: pointer;
  border-bottom: 3px solid transparent;
  margin-bottom: -2px;
  font-size: 1rem;
}
.day-tab:hover { color: var(--cosmic); }
.day-tab.active {
  color: var(--navy);
  border-bottom-color: var(--orange);
}
.track-filter {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 24px 0;
}
.track-pill {
  background: #fff;
  border: 1px solid var(--line);
  padding: 8px 16px;
  border-radius: 999px;
  font-size: 0.88rem;
  font-weight: 500;
  cursor: pointer;
  color: var(--slate);
  font-family: var(--body);
}
.track-pill:hover { border-color: var(--cosmic); color: var(--cosmic); }
.track-pill.active {
  background: var(--cosmic);
  color: #fff;
  border-color: var(--cosmic);
}
.session {
  background: #fff;
  border: 1px solid var(--line);
  border-left: 4px solid var(--orange);
  padding: 18px 22px;
  border-radius: var(--radius);
  margin-bottom: 12px;
  display: grid;
  grid-template-columns: 100px 1fr auto;
  gap: 18px;
  align-items: center;
}
@media (max-width: 700px) {
  .session { grid-template-columns: 1fr; gap: 6px; }
}
.session-time {
  font-family: var(--display);
  font-weight: 700;
  color: var(--navy);
  font-size: 1.05rem;
}
.session-title { font-weight: 600; color: var(--navy); margin-bottom: 4px; font-size: 1.02rem; }
.session-meta { color: var(--slate-soft); font-size: 0.88rem; }
.session-meta span + span::before {
  content: '·';
  margin: 0 8px;
}
.tag {
  display: inline-block;
  background: var(--white);
  color: var(--cosmic);
  padding: 4px 10px;
  border-radius: 4px;
  font-size: 0.78rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  border: 1px solid var(--line);
}
.tag-tech { background: #DDEBF7; color: var(--cosmic); }
.tag-policy { background: #FEF1E2; color: var(--orange-dark); }
.tag-industry { background: #E8F5E8; color: #2D6A2D; }
.tag-research { background: #F1E8F7; color: #6B3D8C; }

.session.hidden { display: none; }

/* ---- Form ---- */
.form-wrap {
  max-width: 640px;
  margin: 0 auto;
  background: #fff;
  padding: 32px;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}
.form-row { margin-bottom: 18px; }
.form-row label {
  display: block;
  font-weight: 600;
  color: var(--navy);
  margin-bottom: 6px;
  font-size: 0.95rem;
}
.form-row .req { color: var(--orange); margin-left: 2px; }
.form-row input[type="text"],
.form-row input[type="email"],
.form-row input[type="tel"],
.form-row textarea,
.form-row select {
  width: 100%;
  padding: 11px 14px;
  border: 1.5px solid var(--line);
  border-radius: 6px;
  font-family: var(--body);
  font-size: 1rem;
  color: var(--slate);
  background: #fff;
  transition: border-color 0.15s, box-shadow 0.15s;
}
.form-row input:focus, .form-row textarea:focus, .form-row select:focus {
  outline: none;
  border-color: var(--cosmic);
  box-shadow: 0 0 0 3px rgba(31, 58, 104, 0.15);
}
.form-row textarea { min-height: 90px; resize: vertical; }
.form-row .help { font-size: 0.85rem; color: var(--slate-soft); margin-top: 4px; }
.form-row.invalid input,
.form-row.invalid textarea,
.form-row.invalid select {
  border-color: #C0392B;
}
.error-msg {
  display: none;
  color: #C0392B;
  font-size: 0.86rem;
  margin-top: 4px;
  font-weight: 500;
}
.form-row.invalid .error-msg { display: block; }

.radio-group {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
}
@media (max-width: 540px) { .radio-group { grid-template-columns: 1fr; } }
.radio-option {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 14px;
  border: 1.5px solid var(--line);
  border-radius: 6px;
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s;
}
.radio-option:hover { border-color: var(--cosmic); }
.radio-option input { margin: 0; }
.radio-option.selected {
  border-color: var(--cosmic);
  background: rgba(31, 58, 104, 0.04);
}
.checkbox-row {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  margin-bottom: 18px;
  font-size: 0.92rem;
}
.checkbox-row input { margin-top: 4px; }

.form-success {
  display: none;
  background: #E8F5E8;
  border: 1px solid #4CAF50;
  border-radius: 6px;
  padding: 18px 22px;
  color: #2D6A2D;
  margin-bottom: 18px;
}
.form-success.show { display: block; }
.form-success h3 { color: #2D6A2D; margin: 0 0 6px; font-size: 1.1rem; }

/* ---- Booth tiers ---- */
.tier-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
  margin-top: 30px;
}
@media (max-width: 900px) { .tier-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 500px) { .tier-grid { grid-template-columns: 1fr; } }
.tier {
  background: #fff;
  border: 1.5px solid var(--line);
  border-radius: var(--radius);
  padding: 22px;
  text-align: center;
}
.tier.featured { border-color: var(--orange); position: relative; }
.tier.featured::before {
  content: 'Most Popular';
  position: absolute;
  top: -10px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--orange);
  color: #fff;
  padding: 3px 12px;
  border-radius: 999px;
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.tier h3 { font-size: 1.2rem; margin-bottom: 4px; }
.tier .price {
  font-family: var(--display);
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--navy);
  margin: 6px 0 14px;
}
.tier ul {
  list-style: none;
  padding: 0;
  text-align: left;
  font-size: 0.92rem;
  margin-bottom: 18px;
}
.tier ul li {
  padding: 6px 0;
  border-bottom: 1px solid var(--line);
}
.tier ul li:last-child { border-bottom: none; }
.tier ul li::before {
  content: '\2713';
  color: var(--orange);
  font-weight: 700;
  margin-right: 8px;
}

/* ---- Exhibitor grid ---- */
.exhibitor-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
  margin-top: 24px;
}
@media (max-width: 900px) { .exhibitor-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 500px) { .exhibitor-grid { grid-template-columns: 1fr; } }
.exhibitor {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px 18px;
  text-align: center;
}
.exhibitor-mark {
  width: 56px;
  height: 56px;
  margin: 0 auto 10px;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--cosmic), var(--orange));
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-family: var(--display);
  font-weight: 700;
  font-size: 1.4rem;
}
.exhibitor h4 { font-family: var(--display); margin: 0 0 4px; font-size: 1rem; color: var(--navy); }
.exhibitor p { font-size: 0.85rem; color: var(--slate-soft); margin: 0; }

/* ---- CTA band ---- */
.cta-band {
  background: linear-gradient(135deg, var(--orange), #E89A4D);
  color: #fff;
  text-align: center;
  padding: 60px 20px;
}
.cta-band h2 { color: #fff; }
.cta-band p { color: rgba(255,255,255,0.95); margin-bottom: 24px; }
.cta-band .btn-ghost { border-color: #fff; }

/* ---- Footer ---- */
.site-footer {
  background: var(--navy);
  color: rgba(255,255,255,0.75);
  padding: 50px 20px 24px;
  font-size: 0.92rem;
}
.footer-inner {
  max-width: var(--container);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
}
@media (max-width: 800px) { .footer-inner { grid-template-columns: 1fr 1fr; gap: 24px; } }
@media (max-width: 480px) { .footer-inner { grid-template-columns: 1fr; } }
.footer-col h4 {
  font-family: var(--display);
  color: #fff;
  font-size: 0.95rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 14px;
}
.footer-col ul { list-style: none; padding: 0; margin: 0; }
.footer-col li { margin-bottom: 8px; }
.footer-col a { color: rgba(255,255,255,0.75); }
.footer-col a:hover, .footer-col a:focus { color: #fff; text-decoration: underline; }
.footer-brand p { color: rgba(255,255,255,0.7); }
.footer-bottom {
  max-width: var(--container);
  margin: 30px auto 0;
  padding-top: 24px;
  border-top: 1px solid rgba(255,255,255,0.1);
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 0.85rem;
  color: rgba(255,255,255,0.55);
}

/* ---- Helpers ---- */
.text-center { text-align: center; }
.mt-0 { margin-top: 0; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }
.mb-0 { margin-bottom: 0; }
.flex-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}
.lead { font-size: 1.1rem; color: var(--slate); }

/* visually hidden but available to screen readers */
.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px; overflow: hidden;
  clip: rect(0,0,0,0); white-space: nowrap; border: 0;
}

/* reduced motion */
@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; animation: none !important; scroll-behavior: auto !important; }
}