@layer reset, base, layout, components, utilities;

@layer reset {
  *, *::before, *::after { box-sizing: border-box; }
  body, h1, h2, h3, p, ul, ol, dl, dd { margin: 0; }
  button, input, textarea, select { font: inherit; }
  img, svg { display: block; max-width: 100%; }
  [hidden] { display: none !important; }
}

@layer base {
  /* Compact conference layout: existing green identity, native CSS, static content. */
  :root {
    color-scheme: light dark;
    --paper: #fafaf7;
    --ink: #26372e;
    --muted: #59675f;
    --line: #d5dcd5;
    --input-border: #87928a;
    --primary: #193f35;
    --on-primary: #fafcf9;
    --button-hover: #285348;
    --surface: #fefefa;
    --tint: #edf1eb;
    --red: #9e2929;
    --error-tint: #fbefec;
    --disabled-bg: #e2e7df;
    --disabled-text: #53614f;
  }
  @media (prefers-color-scheme: dark) {
    :root {
      --paper: #18211d;
      --ink: #e9efea;
      --muted: #b2c0b7;
      --line: #3e5045;
      --input-border: #7b9082;
      --primary: #b8d3c1;
      --on-primary: #182b21;
      --button-hover: #d0e3d6;
      --surface: #1e2a23;
      --tint: #28392e;
      --red: #f1a0a0;
      --error-tint: #382929;
      --disabled-bg: #334238;
      --disabled-text: #b4c2b7;
    }
  }
  html { scroll-behavior: smooth; scroll-padding-top: 24px; }
  body { background: var(--paper); color: var(--ink); font: 16px/1.6 -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif; -webkit-font-smoothing: antialiased; }
  a { color: inherit; text-underline-offset: .2em; }
  a:hover { text-decoration-thickness: 2px; }
  :focus-visible { outline: 3px solid var(--primary); outline-offset: 4px; }
  ::selection { background: var(--primary); color: var(--on-primary); }
  h1, h2, h3 { font-weight: 600; line-height: 1.2; }
  h1 { font-size: clamp(2.2rem, 4vw, 3rem); letter-spacing: -.035em; }
  h2 { font-size: 1.4rem; letter-spacing: -.025em; }
  h3 { font-size: 1.05rem; }
  p + p { margin-top: 12px; }
  small { font-size: .85rem; }
}

@layer layout {
  .container { width: min(1080px, calc(100% - 64px)); margin-inline: auto; }
  .site-header { display: flex; align-items: center; justify-content: space-between; min-height: 80px; gap: 32px; border-bottom: 1px solid var(--line); }
  .brand { display: flex; align-items: center; gap: 11px; text-decoration: none; flex-shrink: 0; }
  .brand-mark { width: 35px; height: 35px; }
  .brand-name { font-size: 1.35rem; font-weight: 650; letter-spacing: -.045em; line-height: 1; }
  .brand-name span { font-weight: 400; margin-left: 3px; }
  .brand-location { display: block; font-size: .58rem; letter-spacing: .18em; margin-top: 7px; }
  .nav-links { display: flex; align-items: center; gap: 30px; }
  .nav-links > a { font-size: .9rem; text-decoration: none; padding-block: 10px; }
  .nav-links > a:hover, .nav-links > a[aria-current='page'] { text-decoration: underline; }
  .hero { display: grid; grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr); align-items: center; gap: 64px; padding-block: 70px; }
  .hero h1 { font-size: clamp(3rem, 6vw, 4.7rem); letter-spacing: -.055em; }
  .hero-description { font-size: 1.3rem; margin-top: 12px; }
  .hero-location { color: var(--muted); }
  .conference-details { display: grid; gap: 18px; }
  .conference-details > div { display: grid; grid-template-columns: 1fr 1.1fr; gap: 20px; font-size: .9rem; }
  .conference-details dt { color: var(--muted); }
  .conference-details dd { font-weight: 500; }
  .meeting-section { padding-block: 38px; border-top: 1px solid var(--line); }
  .meeting-section p { max-width: 65ch; margin-top: 12px; color: var(--muted); }
  .information-columns { display: grid; grid-template-columns: 1fr 1fr; gap: 80px; padding-block: 12px 42px; }
  .information-columns p { max-width: 43ch; margin-top: 12px; color: var(--muted); }
  .abstracts-summary { display: flex; gap: 40px; justify-content: space-between; align-items: center; padding-block: 34px 42px; border-top: 1px solid var(--line); }
  .abstracts-summary p { max-width: 62ch; margin-top: 12px; color: var(--muted); }
  .hero-actions { display: flex; align-items: center; gap: 16px; flex-wrap: wrap; margin-top: 26px; }
  .site-footer { display: flex; justify-content: space-between; gap: 28px; border-top: 1px solid var(--line); padding-block: 24px; font-size: .8rem; color: var(--muted); }
  .footer-links { display: flex; flex-wrap: wrap; gap: 22px; }
  .page-heading { padding-block: 42px 28px; border-bottom: 1px solid var(--line); }
  .page-heading p { margin-top: 12px; color: var(--muted); max-width: 65ch; }
  .form-layout { display: grid; grid-template-columns: 240px minmax(0, 1fr); gap: 64px; align-items: start; padding-block: 32px 64px; }
  .form-sidebar { position: sticky; top: 24px; }
  .form-sidebar h2 { font-size: 1.05rem; margin-bottom: 20px; }
  .guideline { font-size: .86rem; margin-bottom: 20px; }
  .guideline strong { display: block; font-weight: 600; margin-bottom: 5px; }
  .guideline p { color: var(--muted); }
  .abstract-form { padding: 0; }
  .form-section { border: 0; padding: 0; margin: 0 0 30px; min-width: 0; }
  .form-section > legend { width: 100%; padding: 0 0 12px; margin-bottom: 20px; border-bottom: 1px solid var(--line); font-weight: 600; font-size: 1.05rem; }
  .form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
  .field { margin-bottom: 20px; }
  .field:last-child { margin-bottom: 0; }
  .field > label, .field-label { display: block; font-size: .9rem; font-weight: 550; margin-bottom: 7px; }
  .required { color: var(--ink); }
  .optional { font-weight: 400; color: var(--muted); font-size: .8rem; margin-left: 4px; }
  input[type='text'], input[type='email'], textarea { display: block; width: 100%; border: 1px solid var(--input-border); border-radius: 3px; background: var(--surface); color: var(--ink); padding: 10px 12px; font-size: 1rem; line-height: 1.5; }
  textarea { resize: vertical; min-height: 95px; }
  #abstractText { min-height: 225px; }
  input:focus, textarea:focus { outline: 2px solid var(--primary); outline-offset: 2px; }
  input::placeholder, textarea::placeholder { color: var(--muted); opacity: 1; }
  input[readonly], textarea[readonly] { background: var(--tint); }
  .help-text { font-size: .82rem; color: var(--muted); margin-top: 7px; }
  .required-note { margin-top: 0; margin-bottom: 24px; }
  .text-meta { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; margin-top: 7px; }
  .text-meta .help-text { margin: 0; }
  .word-count { font-size: .82rem; white-space: nowrap; }
  .preference-options { display: flex; flex-wrap: wrap; gap: 4px 24px; }
  .radio-option { display: flex; align-items: center; gap: 9px; min-height: 44px; font-size: .9rem; cursor: pointer; }
  input[type='radio'], input[type='checkbox'] { accent-color: var(--primary); width: 17px; height: 17px; flex-shrink: 0; }
  .privacy-section { margin-bottom: 0; }
  .privacy-check { display: flex; align-items: start; gap: 10px; font-size: .86rem; }
  .privacy-check input { margin-top: 5px; }
  .submit-row { border-top: 1px solid var(--line); padding-top: 22px; margin-top: 24px; display: flex; align-items: center; gap: 20px; flex-wrap: wrap; }
  .submit-row p { color: var(--muted); font-size: .8rem; max-width: 260px; }
  .prose { max-width: 790px; padding-block: 34px 64px; }
  .prose h2 { font-size: 1.25rem; margin: 28px 0 12px; }
  .prose p, .prose ul { font-size: .95rem; color: var(--muted); }
  .prose ul { padding-left: 22px; margin-top: 13px; }
  .prose li + li { margin-top: 7px; }
  .receipt { max-width: 720px; margin: 56px auto 72px; }
  .receipt h1 { margin-block: 16px 22px; }
  .receipt p { color: var(--muted); font-size: .95rem; }
  .reference-box { background: var(--tint); padding: 22px; margin-block: 24px; border-radius: 3px; }
  .reference-box span { display: block; font-size: .82rem; margin-bottom: 7px; }
  .reference-box strong { font: 600 1.7rem ui-monospace, monospace; letter-spacing: -.025em; }
}

@layer components {
  .skip-link { position: absolute; left: 15px; top: -100px; background: var(--primary); color: var(--on-primary); padding: 10px 20px; z-index: 1; }
  .skip-link:focus { top: 15px; }
  .eyebrow { color: var(--muted); font-size: .85rem; }
  .button { display: inline-flex; align-items: center; justify-content: center; gap: 12px; border: 1px solid var(--primary); border-radius: 3px; background: var(--primary); color: var(--on-primary); padding: 10px 18px; text-decoration: none; font-size: .9rem; font-weight: 500; cursor: pointer; min-height: 44px; white-space: nowrap; transition: background .15s, opacity .15s; }
  .button:hover { background: var(--button-hover); }
  .button:active { opacity: .8; }
  .button.secondary { background: transparent; color: var(--primary); }
  .button.secondary:hover { background: var(--tint); }
  .button:disabled { background: var(--disabled-bg); border-color: var(--input-border); color: var(--disabled-text); cursor: not-allowed; opacity: 1; }
  .text-link { font-size: .9rem; }
  .notice { padding: 12px 14px; border-left: 2px solid var(--input-border); background: var(--tint); font-size: .82rem; }
  .status-banner { display: flex; align-items: center; gap: 11px; padding: 12px 14px; background: var(--tint); border-radius: 3px; margin-bottom: 24px; font-size: .85rem; }
  .status-dot { width: 7px; height: 7px; border: 1px solid var(--muted); border-radius: 50%; flex-shrink: 0; }
  .status-banner.open .status-dot { background: var(--primary); border-color: var(--primary); }
  .error-message { color: var(--red); font-size: .82rem; margin-top: 6px; }
  [aria-invalid='true'] { border-color: var(--red) !important; }
  .form-alert { background: var(--error-tint); border-left: 2px solid var(--red); padding: 14px; margin-bottom: 22px; font-size: .9rem; }
  .over-limit { color: var(--red); font-weight: 600; }
  .mobile-toggle { display: none; border: 1px solid var(--input-border); border-radius: 3px; background: transparent; padding: 8px 12px; min-height: 44px; color: var(--ink); font-size: .85rem; }
  #turnstile-container { margin-top: 18px; }
}

@layer utilities {
  .sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; }
  .mt-24 { margin-top: 24px; }
  @media (max-width: 1000px) {
    .hero { gap: 32px; }
    .conference-details > div { grid-template-columns: 1fr; gap: 2px; }
    .form-layout { grid-template-columns: 210px minmax(0, 1fr); gap: 36px; }
    .form-row { grid-template-columns: 1fr; gap: 0; }
  }
  @media (max-width: 767px) {
    .container { width: calc(100% - 40px); }
    .site-header { min-height: 72px; flex-wrap: wrap; gap: 0; }
    .mobile-toggle { display: block; }
    .nav-links { width: 100%; display: none; flex-direction: column; align-items: stretch; gap: 0; padding: 10px 0 18px; }
    .nav-links.expanded { display: flex; }
    .nav-links > a { min-height: 44px; }
    .hero { grid-template-columns: 1fr; padding-block: 36px 32px; gap: 28px; }
    .hero h1 { font-size: clamp(2.7rem, 10vw, 3.5rem); }
    .hero-description { font-size: 1.1rem; }
    .conference-details { gap: 12px; }
    .conference-details > div { grid-template-columns: 1fr 1fr; gap: 14px; font-size: .85rem; }
    .meeting-section { padding-block: 28px; }
    .information-columns { grid-template-columns: 1fr; gap: 28px; padding-block: 0 30px; }
    .abstracts-summary { flex-direction: column; align-items: start; gap: 20px; padding-block: 28px 34px; }
    .site-footer { flex-direction: column; gap: 12px; padding-block: 20px; }
    .page-heading { padding-block: 30px 22px; }
    .form-layout { grid-template-columns: 1fr; gap: 38px; padding-block: 24px 44px; }
    .form-main { grid-row: 1; }
    .form-sidebar { position: static; grid-row: 2; border-top: 1px solid var(--line); padding-top: 24px; }
    .preference-options { flex-direction: column; gap: 0; }
    .submit-row { flex-direction: column; align-items: stretch; gap: 12px; }
    .submit-row p { max-width: none; }
    .text-meta { flex-wrap: wrap; gap: 5px; }
    .receipt { margin-block: 36px 48px; }
    .reference-box strong { font-size: 1.4rem; }
  }
  @media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    *, *::before, *::after { transition: none !important; animation: none !important; }
  }
}