:root {
  --primary: #003366;
  --secondary: #1f92ab;
  --accent: #ffb800;
  --accent-deep: #d4a017;
  --neutral: #677d86;
  --ink: #080811;
  --panel: #1c1c1c;
  --paper: #ffffff;
  --muted: #e2e6e7;
  --hero-image: url("assets/conference-desktop.jpg");
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--paper);
  color: #333333;
  font-family: "Montserrat", Arial, sans-serif;
}

a {
  color: inherit;
  text-decoration: none;
}

.hero {
  min-height: 1080px;
  position: relative;
  display: grid;
  grid-template-rows: auto 1fr auto;
  padding: 56px 80px 16px;
  overflow: hidden;
  background-image:
    linear-gradient(rgba(64, 52, 36, 0.72), rgba(64, 52, 36, 0.72)),
    var(--hero-image);
  background-position: center top;
  background-size: cover;
  border-bottom: 12px solid #ffffff;
}

.hero::after {
  content: "";
  position: absolute;
  inset: auto 0 0;
  height: 280px;
  background: linear-gradient(
    to bottom,
    rgba(8, 8, 17, 0),
    rgba(8, 8, 17, 0.52)
  );
  pointer-events: none;
}

.topbar {
  position: relative;
  z-index: 3;
  height: 80px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  padding: 0 32px;
  border: 1px solid #6c6c6c;
  border-radius: 24px;
  background: var(--panel);
}

.brand {
  display: flex;
  align-items: center;
}

.brand img {
  width: 199px;
  height: auto;
  display: block;
  contain: layout;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 52px;
  color: rgba(255, 255, 255, 0.9);
  font-family: "Barlow", Arial, sans-serif;
  font-size: 16px;
  font-weight: 600;
}

.nav-links a {
  position: relative;
  padding: 10px 0;
}

.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 2px;
  height: 3px;
  border-radius: 999px;
  background: var(--accent);
  transform: scaleX(0);
  transition: transform 180ms ease;
}

.nav-links a:hover::after,
.nav-links a:focus-visible::after {
  transform: scaleX(1);
}

.menu-button {
  display: none;
  width: 44px;
  height: 44px;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 5px;
  border: 0;
  border-radius: 8px;
  background: transparent;
  cursor: pointer;
}

.menu-button span {
  width: 22px;
  height: 2px;
  border-radius: 999px;
  background: #ffffff;
}

.hero-content {
  position: relative;
  z-index: 2;
  align-self: center;
  justify-self: center;
  width: min(960px, 100%);
  margin-top: -52px;
  text-align: center;
  color: #ffffff;
}

.hero-content h1 {
  margin: 0 0 32px;
  color: #ffffff;
  font-size: clamp(48px, 5vw, 72px);
  font-weight: 800;
  line-height: 1;
}

.hero-content p {
  margin: 0 auto 44px;
  max-width: 816px;
  color: rgba(255, 255, 255, 0.82);
  font-size: 24px;
  font-weight: 600;
  line-height: 1.2;
}

.event-meta {
  display: grid;
  gap: 16px;
  justify-content: center;
  margin-bottom: 72px;
  color: #ffffff;
  font-size: 24px;
  font-weight: 700;
}

.event-meta span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 14px;
}

.event-meta svg {
  width: 25px;
  height: 25px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 48px;
}

.button {
  min-width: 280px;
  min-height: 52px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 12px;
  padding: 13px 28px;
  font-size: 24px;
  font-weight: 700;
  line-height: 1;
  transition:
    transform 180ms ease,
    box-shadow 180ms ease,
    background 180ms ease;
}

.button:hover,
.button:focus-visible {
  transform: translateY(-2px);
}

.button-primary {
  background: var(--accent);
  color: #1c1c1c;
  box-shadow: 0 18px 38px rgba(0, 0, 0, 0.22);
}

.button-secondary {
  border: 3px solid var(--muted);
  color: var(--muted);
  background: rgba(2, 17, 29, 0.08);
  backdrop-filter: blur(6px);
}

.section {
  width: min(1760px, calc(100% - 40px));
  margin: 0 auto;
  padding: 112px 0 0;
}

.about {
  padding-top: 112px;
}

.section-heading {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-bottom: 44px;
}

.section-heading h2 {
  margin: 0;
  color: #333333;
  font-size: clamp(34px, 4vw, 48px);
  font-weight: 700;
  line-height: 1.1;
}

.section-heading span {
  width: 151px;
  height: 6px;
  border-radius: 999px;
  background: var(--accent);
}

.about-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.95fr) minmax(420px, 0.9fr);
  align-items: center;
  gap: 120px;
}

.about-grid p {
  margin: 0;
  color: #333333;
  font-size: 24px;
  font-weight: 500;
  line-height: 1.59;
}

.about-grid img {
  width: 100%;
  height: 260px;
  display: block;
  border-radius: 24px;
  object-fit: cover;
  box-shadow: 0 24px 60px rgba(8, 8, 17, 0.18);
  content-visibility: auto;
  contain: layout style paint;
}

.timeline-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.timeline-grid article {
  min-height: 190px;
  padding: 28px;
  border: 2px solid rgba(255, 184, 0, 0.55);
  border-radius: 16px;
  background: #ffffff;
  box-shadow: 0 18px 45px rgba(8, 8, 17, 0.08);
}

/* Center timeline entries on wider screens so single-line items align visually */
.timeline-grid article {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
}

/* Place the conference box in the middle column on wider screens */
@media (min-width: 901px) {
  .timeline-grid article.center {
    grid-column: 2 / 3;
    justify-self: center;
    align-self: start;
    width: 100%;
    max-width: 420px;
  }
}

.timeline-grid span {
  color: var(--secondary);
  font-size: 14px;
  font-weight: 800;
  text-transform: uppercase;
}

.timeline-grid h3,
.track-card h3 {
  margin: 12px 0;
  color: var(--ink);
  font-size: 24px;
  line-height: 1.25;
}

.timeline-grid p {
  margin: 0;
  color: #4c5b61;
  font-size: 16px;
  line-height: 1.7;
}

.track-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 48px 104px;
}

.track-card {
  position: relative;
  min-height: 225px;
  display: grid;
  grid-template-columns: 84px 1fr;
  border: 2px solid var(--accent);
  border-radius: 16px;
  background: #ffffff;
  overflow: hidden;
}

.track-card b {
  display: flex;
  align-items: center;
  justify-content: center;
  color: #ffffff;
  background: #283337;
  font-size: 56px;
  font-weight: 800;
  letter-spacing: 3.92px;
  writing-mode: vertical-rl;
  transform: rotate(180deg);
}

.track-card:nth-child(2) b {
  background: #2b5a66;
}

.track-card:nth-child(3) b {
  background: #52646c;
}

.track-card:nth-child(4) b {
  background: #0d5b6c;
}

.track-card div {
  padding: 26px 32px 24px;
}

.track-card ul {
  margin: 0;
  padding-left: 22px;
  color: var(--ink);
  font-size: 16px;
  font-weight: 500;
  line-height: 1.59;
}

.submission {
  padding-top: 120px;
}

.guidelines {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: 22px;
}

.guideline-item {
  display: grid;
  grid-template-columns: 52px 1fr;
  gap: 22px;
  align-items: start;
  min-height: 190px;
  padding: 28px;
  border: 2px solid rgba(255, 184, 0, 0.55);
  border-radius: 16px;
  background: #ffffff;
  box-shadow: 0 18px 45px rgba(8, 8, 17, 0.08);
}

.guideline-card {
  display: block;
  min-height: 0;
  padding: 24px 28px;
}

.guideline-card:nth-child(-n + 2) {
  grid-column: span 3;
}

.guideline-card:nth-child(n + 3) {
  grid-column: span 2;
}

.guideline-card-compact {
  padding: 22px 24px;
}

.guideline-item b {
  width: 46px;
  height: 46px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 14px;
  background: var(--primary);
  color: #ffffff;
  font-size: 18px;
  font-weight: 800;
  line-height: 1;
}

.guideline-item h3 {
  margin: 0 0 12px;
  color: var(--ink);
  font-size: 18px;
  font-weight: 700;
  line-height: 1.3;
}

.guideline-item p {
  margin: 0;
  color: #4c5b61;
  font-size: 16px;
  font-weight: 500;
  line-height: 1.7;
}

.template-details,
.submission-steps {
  margin: 16px 0 0;
  padding: 0;
  color: #4c5b61;
  font-size: 16px;
  font-weight: 500;
  line-height: 1.55;
}

.template-details {
  padding-left: 20px;
}

.template-details li + li {
  margin-top: 4px;
}

.template-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 18px;
}

.template-actions .button {
  min-width: 0;
  min-height: 42px;
  border-width: 2px;
  border-radius: 10px;
  padding: 10px 18px;
  font-size: 15px;
}

.template-actions .button-secondary {
  border-color: var(--primary);
  color: var(--primary);
  background: transparent;
  backdrop-filter: none;
}

.submission-steps {
  list-style: none;
  counter-reset: submission-step;
}

.submission-steps li {
  counter-increment: submission-step;
  display: grid;
  grid-template-columns: 34px 1fr;
  gap: 14px;
  align-items: start;
}

.submission-steps li + li {
  margin-top: 10px;
}

.submission-steps li::before {
  content: counter(submission-step);
  width: 34px;
  height: 34px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
  background: var(--primary);
  color: #ffffff;
  font-size: 15px;
  font-weight: 800;
  line-height: 1;
}

.submission-note {
  margin-top: 32px;
  padding: 0;
  border-radius: 16px;
  background: transparent;
}

.submission-note p {
  margin: 0;
  color: rgba(255, 255, 255, 0.84);
  font-size: 17px;
  font-weight: 600;
  line-height: 1.45;
}

.submit-paper-callout {
  display: grid;
  align-items: center;
  justify-items: center;
  border: 0;
  box-shadow: none;
}

.submit-paper-callout .button {
  min-width: min(420px, 100%);
  min-height: 68px;
  border: 2px solid rgba(255, 255, 255, 0.72);
  border-radius: 12px;
  padding: 18px 42px;
  font-size: 22px;
  font-weight: 800;
  color: var(--ink);
  background: linear-gradient(180deg, #ffcf3a 0%, var(--accent) 100%);
  box-shadow:
    0 20px 44px rgba(255, 184, 0, 0.32),
    0 8px 18px rgba(8, 8, 17, 0.16);
  text-transform: uppercase;
}

.submit-paper-callout .button:hover,
.submit-paper-callout .button:focus-visible {
  box-shadow:
    0 24px 52px rgba(255, 184, 0, 0.42),
    0 10px 22px rgba(8, 8, 17, 0.18);
}

.brochure {
  padding-top: 64px;
}

.brochure-band {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  padding: 38px 44px;
  border-radius: 16px;
  background: #1c1c1c;
  color: #ffffff;
  box-shadow: 0 20px 52px rgba(8, 8, 17, 0.16);
}

.brochure-band p {
  margin: 0 0 10px;
  color: var(--accent);
  font-size: 14px;
  font-weight: 800;
  text-transform: uppercase;
}

.brochure-band h2 {
  margin: 0 0 10px;
  font-size: clamp(28px, 4vw, 42px);
  line-height: 1.15;
}

.brochure-band span {
  display: block;
  color: rgba(255, 255, 255, 0.74);
  font-size: 16px;
  line-height: 1.6;
}

.brochure-band .button[aria-disabled="true"] {
  cursor: not-allowed;
  opacity: 0.82;
}

.site-footer {
  margin-top: 160px;
  padding: 0 20px 56px;
  background: #0c0c0c;
  color: #ffffff;
  text-align: center;
}

.footer-callout {
  width: min(1286px, 100%);
  margin: 0 auto;
  transform: translateY(-84px);
  display: grid;
  justify-items: center;
  gap: 18px;
  padding: 44px;
  border: 1px solid #ffffff;
  border-radius: 9px;
  background: #1c1c1c;
}

.footer-callout p {
  margin: 0;
  color: var(--accent);
  font-weight: 800;
  text-transform: uppercase;
}

.footer-callout h2 {
  margin: 0;
  max-width: 900px;
  font-size: clamp(28px, 4vw, 44px);
  line-height: 1.15;
}

.copyright {
  margin: -24px 0 0;
  color: rgba(255, 255, 255, 0.7);
}

.committee {
  padding-top: 112px;
}

.committee-content {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 28px;
}

.committee-group {
  padding: 28px;
  border: 2px solid var(--secondary);
  border-radius: 16px;
  background: #ffffff;
  box-shadow: 0 18px 45px rgba(8, 8, 17, 0.08);
}

.committee-group h3 {
  margin: 0 0 16px;
  color: var(--primary);
  font-size: 18px;
  font-weight: 700;
  line-height: 1.3;
  text-transform: uppercase;
}

.committee-group p {
  margin: 0 0 12px;
  color: #333333;
  font-size: 16px;
  font-weight: 500;
  line-height: 1.6;
}

.committee-group p:last-child {
  margin-bottom: 0;
}

.cmt {
  padding-top: 84px;
}

.cmt-content {
  display: grid;
  grid-template-columns: minmax(200px, 280px) minmax(0, 1fr);
  align-items: center;
  gap: 16px;
  max-width: 1160px;
  margin: 0 auto;
  padding: 12px;
  border: 2px solid var(--secondary);
  border-radius: 16px;
  background: #ffffff;
  box-shadow: 0 18px 45px rgba(8, 8, 17, 0.08);
}

.cmt-text {
  max-width: 760px;
}

.cmt-text p {
  margin: 0;
  color: #333333;
  font-size: 15px;
  font-weight: 500;
  line-height: 1.58;
  text-align: left;
}

.cmt-image {
  max-width: 280px;
}

.cmt-image img {
  width: 100%;
  height: 165px;
  display: block;
  border-radius: 18px;
  object-fit: cover;
  box-shadow: 0 22px 54px rgba(8, 8, 17, 0.16);
}

@media (max-width: 900px) {
  .committee-content {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .committee-group {
    padding: 22px;
  }

  .committee-group h3 {
    font-size: 16px;
  }

  .committee-group p {
    font-size: 15px;
  }

  .cmt {
    padding-top: 56px;
  }

  .cmt-content {
    grid-template-columns: 1fr;
    gap: 14px;
    padding: 14px;
  }

  .cmt-text {
    max-width: none;
  }

  .cmt-text p {
    font-size: 14px;
    line-height: 1.55;
  }

  .cmt-image {
    max-width: none;
  }

  .cmt-image img {
    height: 150px;
  }
}

.advisory-committee {
  padding-top: 112px;
}

.advisory-content {
  display: grid;
  grid-template-columns: 1fr;
  gap: 48px;
}

.advisory-group {
  padding: 28px;
  border: 2px solid var(--secondary);
  border-radius: 16px;
  background: #ffffff;
  box-shadow: 0 18px 45px rgba(8, 8, 17, 0.08);
}

.advisory-group h3 {
  margin: 0 0 24px;
  color: var(--primary);
  font-size: 20px;
  font-weight: 700;
  line-height: 1.3;
  text-transform: uppercase;
}

.committee-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 15px;
}

.committee-table thead {
  background-color: var(--secondary);
  color: white;
}

.committee-table th {
  padding: 14px;
  text-align: left;
  font-weight: 700;
  border: 1px solid #ddd;
  font-size: 14px;
}

.committee-table td {
  padding: 12px 14px;
  border: 1px solid #ddd;
  color: #333333;
}

.committee-table tbody tr:nth-child(odd) {
  background-color: #f9f9f9;
}

.committee-table tbody tr:hover {
  background-color: #f0f8ff;
}

@media (max-width: 900px) {
  .advisory-content {
    gap: 32px;
  }

  .advisory-group {
    padding: 22px;
  }

  .advisory-group h3 {
    font-size: 18px;
  }

  .committee-table th {
    padding: 12px 10px;
    font-size: 13px;
  }

  .committee-table td {
    padding: 10px;
    font-size: 14px;
  }
}

@media (max-width: 1100px) {
  :root {
    --hero-image: url("assets/conference-mobile.jpg");
  }

  .hero {
    min-height: 915px;
    padding: 48px 24px 32px;
    background-image:
      linear-gradient(
        180deg,
        rgba(2, 17, 29, 0.85),
        rgba(2, 17, 29, 0.72) 45%,
        rgba(2, 17, 29, 0.6) 82%,
        rgba(2, 17, 29, 0)
      ),
      var(--hero-image);
    background-position: center top;
    border-bottom: 10px solid var(--ink);
  }

  .topbar {
    height: 48px;
    padding: 0 14px 0 16px;
    border-radius: 8px;
    background: #02101c;
  }

  .brand img {
    width: 92px;
  }

  .menu-button {
    display: flex;
  }

  .nav-links {
    position: absolute;
    left: 0;
    right: 0;
    top: 58px;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 8px;
    border: 1px solid #6c6c6c;
    border-radius: 8px;
    background: #02101c;
  }

  .nav-links.is-open {
    display: flex;
  }

  .nav-links a {
    padding: 14px;
    text-align: left;
  }

  .hero-content {
    margin-top: 28px;
  }

  .hero-content h1 {
    margin-bottom: 18px;
    font-size: 40px;
    letter-spacing: 0;
  }

  .hero-content p {
    max-width: 319px;
    margin-bottom: 50px;
    font-size: 14px;
    line-height: 1.12;
    text-align: left;
  }

  .event-meta {
    gap: 13px;
    margin-bottom: 56px;
    font-size: 20px;
  }

  .event-meta span {
    gap: 13px;
    justify-content: flex-start;
  }

  .event-meta svg {
    width: 22px;
    height: 22px;
    flex: 0 0 auto;
  }

  .hero-actions {
    flex-direction: column;
    gap: 24px;
  }

  .button {
    min-width: 240px;
    min-height: 48px;
    font-size: 20px;
  }

  .button-secondary {
    border-width: 1.5px;
  }
}

@media (max-width: 900px) {
  .section {
    width: min(100% - 32px, 720px);
    padding-top: 72px;
  }

  .about {
    padding-top: 88px;
  }

  .section-heading {
    gap: 16px;
    margin-bottom: 28px;
  }

  .section-heading span {
    width: 84px;
    height: 4px;
  }

  .about-grid,
  .timeline-grid,
  .track-grid {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .guidelines {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 20px;
  }

  .guideline-card,
  .guideline-card:nth-child(-n + 2),
  .guideline-card:nth-child(n + 3) {
    grid-column: span 2;
  }

  .about-grid p {
    font-size: 17px;
  }

  .about-grid img {
    min-width: 0;
    height: 220px;
  }

  .timeline-grid article {
    min-height: 0;
  }

  .track-card {
    grid-template-columns: 58px 1fr;
    min-height: 0;
  }

  .track-card b {
    font-size: 32px;
    letter-spacing: 2px;
  }

  .track-card div {
    padding: 20px;
  }

  .track-card h3 {
    font-size: 20px;
  }

  .submission {
    padding-top: 72px;
  }

  .guidelines {
    gap: 20px;
  }

  .guideline-item {
    grid-template-columns: 36px 1fr;
    gap: 16px;
    min-height: 0;
    padding: 22px;
  }

  .guideline-item b {
    width: 36px;
    height: 36px;
    border-radius: 12px;
    font-size: 16px;
  }

  .guideline-item h3 {
    font-size: 17px;
  }

  .guideline-item p {
    font-size: 15px;
  }

  .guideline-card-compact {
    padding: 20px;
  }

  .submission-note {
    padding: 22px;
  }

  .submit-paper-callout .button {
    width: 100%;
  }

  .brochure-band {
    align-items: stretch;
    flex-direction: column;
    padding: 28px 22px;
  }

  .brochure-band .button {
    width: 100%;
  }

  .site-footer {
    margin-top: 108px;
  }

  .footer-callout {
    padding: 32px 20px;
  }
}

@media (max-width: 640px) {
  .guidelines {
    grid-template-columns: 1fr;
  }

  .guideline-card,
  .guideline-card:nth-child(-n + 2),
  .guideline-card:nth-child(n + 3) {
    grid-column: 1;
  }
}

@media (max-width: 430px) {
  .hero {
    padding-left: 24px;
    padding-right: 24px;
  }

  .event-meta {
    width: min(326px, 100%);
    margin-left: auto;
    margin-right: auto;
  }

  .event-meta span {
    font-size: 18px;
  }

  .brand img {
    width: 80px;
    height: auto;
  }

  .about-grid img {
    height: 200px;
  }

  .nav-links {
    gap: 0;
    font-size: 14px;
  }
}

@media (max-width: 360px) {
  .brand img {
    width: 70px;
  }

  .hero-content h1 {
    font-size: 32px;
    margin-bottom: 12px;
  }

  .hero-content p {
    font-size: 12px;
    margin-bottom: 30px;
  }

  .button {
    min-width: 200px;
    min-height: 44px;
    font-size: 16px;
    padding: 10px 20px;
  }
}