:root {
  --navy: #1A365D;
  --emerald: #2D6A4F;
  --bg: #F7FAFC;
  --surface: #FDFDFD;
  --surface-2: #EEF4F8;
  --text: #2D3748;
  --muted: #617184;
  --border: #DDE7EF;
  --shadow: 0 16px 38px rgba(26, 54, 93, 0.12);
  --soft-shadow: 0 8px 24px rgba(26, 54, 93, 0.08);
  --radius: 18px;
  --radius-sm: 10px;
  --header-height: 78px;
  --focus: 0 0 0 4px rgba(45, 106, 79, 0.18);
}

[data-theme="dark"] {
  --bg: #0B1120;
  --surface: #111A2E;
  --surface-2: #17243C;
  --text: #E2E8F0;
  --muted: #AAB7C8;
  --border: #273956;
  --shadow: 0 18px 42px rgba(0, 0, 0, 0.34);
  --soft-shadow: 0 10px 28px rgba(0, 0, 0, 0.22);
  --focus: 0 0 0 4px rgba(68, 202, 146, 0.2);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: "Open Sans", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
  font-size: 17px;
  line-height: 1.65;
}

body.menu-open { overflow: hidden; }

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

button, input, textarea, select { font: inherit; }

button { cursor: pointer; }

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

/* ── Skip link ── */
.skip-link {
  position: absolute;
  left: -999px;
  top: 10px;
  background: var(--emerald);
  color: white;
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  z-index: 1000;
}
.skip-link:focus { left: 10px; }

/* ── Header ── */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-height);
  display: flex;
  align-items: center;
  background: color-mix(in srgb, var(--surface) 92%, transparent);
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(16px);
}

.header-inner {
  width: min(1220px, calc(100% - 32px));
  margin: 0 auto;
  display: grid;
  grid-template-columns: auto 1fr auto;
  gap: 22px;
  align-items: center;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--navy);
  font-family: "Montserrat", sans-serif;
  font-weight: 800;
  letter-spacing: -0.03em;
  font-size: 1.35rem;
  white-space: nowrap;
}
[data-theme="dark"] .brand { color: #F8FAFC; }

.brand-mark {
  width: 42px;
  height: 42px;
  border-radius: 14px;
  display: block;
  object-fit: contain;
  box-shadow: var(--soft-shadow);
}

/* ── Desktop nav ── */
.desktop-nav {
  justify-self: center;
  display: flex;
  align-items: center;
  gap: 6px;
}

.nav-link, .nav-trigger {
  border: 0;
  background: transparent;
  color: var(--text);
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  font-weight: 700;
  font-size: 0.94rem;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}
.nav-link:hover, .nav-trigger:hover, .nav-link.active {
  background: var(--surface-2);
  color: var(--navy);
}
[data-theme="dark"] .nav-link:hover,
[data-theme="dark"] .nav-trigger:hover,
[data-theme="dark"] .nav-link.active { color: #FFFFFF; }

/* ── Dropdowns ── */
.dropdown { position: relative; }

.mega-menu, .simple-menu {
  position: absolute;
  top: calc(100% + 14px);
  left: 50%;
  transform: translateX(-50%) translateY(10px);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: 0.2s ease;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 22px;
  box-shadow: var(--shadow);
  padding: 22px;
  min-width: 720px;
}
.simple-menu { min-width: 520px; }

.dropdown:hover .mega-menu,
.dropdown:focus-within .mega-menu,
.dropdown:hover .simple-menu,
.dropdown:focus-within .simple-menu {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translateX(-50%) translateY(0);
}

.mega-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.menu-col h4 {
  margin: 0 0 10px;
  color: var(--emerald);
  font-family: "Montserrat", sans-serif;
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.menu-item {
  display: block;
  padding: 9px 10px;
  border-radius: 10px;
  color: var(--text);
  font-size: 0.94rem;
  font-weight: 600;
}
.menu-item:hover { background: var(--surface-2); color: var(--navy); }
[data-theme="dark"] .menu-item:hover { color: #FFFFFF; }

.skills-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}

/* ── Header actions ── */
.header-actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 10px;
}

.search-wrap { position: relative; width: 260px; }

.search-box {
  width: 100%;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  border-radius: 999px;
  padding: 11px 44px 11px 42px;
  box-shadow: var(--soft-shadow);
  outline: none;
}
.search-box:focus {
  box-shadow: var(--soft-shadow), var(--focus);
  border-color: var(--emerald);
}

.search-icon {
  position: absolute;
  left: 15px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--muted);
}

.suggestions {
  position: absolute;
  top: calc(100% + 10px);
  right: 0;
  width: min(440px, 88vw);
  max-height: 430px;
  overflow: auto;
  padding: 10px;
  display: none;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 18px;
  box-shadow: var(--shadow);
}
.suggestions.visible { display: block; }

.suggestion {
  width: 100%;
  border: 0;
  text-align: left;
  background: transparent;
  color: var(--text);
  padding: 12px;
  border-radius: 12px;
  display: grid;
  gap: 2px;
}
.suggestion:hover, .suggestion:focus { background: var(--surface-2); outline: none; }
.suggestion strong { font-size: 0.95rem; }
.suggestion span { color: var(--muted); font-size: 0.82rem; }

.icon-btn {
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  border-radius: 999px;
  width: 44px;
  height: 44px;
  display: inline-grid;
  place-items: center;
  box-shadow: var(--soft-shadow);
}
.icon-btn:hover, .icon-btn:focus {
  outline: none;
  box-shadow: var(--soft-shadow), var(--focus);
}

.hamburger { display: none; }

/* ── Main ── */
main { min-height: calc(100vh - var(--header-height)); }

.section {
  width: min(1220px, calc(100% - 32px));
  margin: 0 auto;
  padding: 74px 0;
}

/* ── Hero ── */
.hero {
  width: min(1220px, calc(100% - 32px));
  margin: 0 auto;
  padding: 72px 0 46px;
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(310px, 0.9fr);
  gap: 44px;
  align-items: center;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border-radius: 999px;
  background: color-mix(in srgb, var(--emerald) 13%, transparent);
  color: var(--emerald);
  font-weight: 800;
  font-size: 0.86rem;
  letter-spacing: 0.02em;
}

h1, h2, h3, h4 {
  font-family: "Montserrat", sans-serif;
  line-height: 1.15;
  color: var(--text);
  letter-spacing: -0.035em;
}
h1 { font-size: clamp(2.35rem, 6vw, 5rem); margin: 18px 0 18px; }
h2 { font-size: clamp(1.9rem, 4vw, 3.25rem); margin: 0 0 14px; }
h3 { font-size: 1.24rem; margin: 0 0 10px; }

.lead {
  color: var(--muted);
  font-size: clamp(1.04rem, 2vw, 1.25rem);
  max-width: 760px;
}

.hero-actions, .button-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

/* ── Buttons ── */
.btn {
  border: 0;
  border-radius: 12px;
  padding: 12px 18px;
  font-weight: 800;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 46px;
  transition: transform 0.16s ease, box-shadow 0.16s ease, background 0.16s ease;
}
.btn:hover { transform: translateY(-1px); }
.btn-primary { background: var(--navy); color: white; box-shadow: var(--soft-shadow); }
.btn-accent  { background: var(--emerald); color: white; box-shadow: var(--soft-shadow); }
.btn-ghost   { background: var(--surface); color: var(--text); border: 1px solid var(--border); }
.btn-small   { padding: 9px 12px; min-height: 38px; border-radius: 10px; font-size: 0.9rem; }

/* ── Hero panel ── */
.hero-panel {
  background: linear-gradient(145deg, color-mix(in srgb, var(--surface) 88%, var(--navy)), var(--surface));
  border: 1px solid var(--border);
  border-radius: 30px;
  padding: 26px;
  box-shadow: var(--shadow);
  position: relative;
  overflow: hidden;
}
.hero-panel:before {
  content: "";
  position: absolute;
  inset: -70px -80px auto auto;
  width: 210px;
  height: 210px;
  border-radius: 50%;
  background: color-mix(in srgb, var(--emerald) 28%, transparent);
}

.score-card { position: relative; display: grid; gap: 16px; }

.score-top {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  align-items: flex-start;
}

.score-number {
  font-family: "Montserrat", sans-serif;
  font-size: 4.4rem;
  line-height: 1;
  font-weight: 800;
  color: var(--navy);
}
[data-theme="dark"] .score-number { color: #BEE3F8; }

.progress-list { display: grid; gap: 12px; }

.progress-item span {
  display: flex;
  justify-content: space-between;
  font-size: 0.9rem;
  font-weight: 700;
  margin-bottom: 6px;
}

.bar {
  height: 10px;
  background: var(--surface-2);
  border-radius: 999px;
  overflow: hidden;
}
.bar i {
  display: block;
  height: 100%;
  width: var(--value);
  border-radius: inherit;
  background: linear-gradient(90deg, var(--emerald), #52B788);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
  margin-top: 18px;
}

.stat {
  padding: 16px;
  border-radius: 18px;
  background: var(--surface);
  border: 1px solid var(--border);
}
.stat strong {
  display: block;
  font-family: "Montserrat", sans-serif;
  font-size: 1.35rem;
  color: var(--emerald);
}

/* ── Section head ── */
.section-head {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  align-items: end;
  margin-bottom: 28px;
}
.section-head p { max-width: 740px; margin: 0; color: var(--muted); }

/* ── Grids ── */
.grid   { display: grid; gap: 20px; }
.grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

/* ── Cards ── */
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px;
  box-shadow: var(--soft-shadow);
}

.link-card {
  display: grid;
  gap: 12px;
  min-height: 190px;
  transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
}
.link-card:hover {
  transform: translateY(-4px);
  border-color: color-mix(in srgb, var(--emerald) 45%, var(--border));
  box-shadow: var(--shadow);
}

.card-icon {
  width: 48px;
  height: 48px;
  border-radius: 16px;
  display: grid;
  place-items: center;
  background: color-mix(in srgb, var(--navy) 10%, transparent);
  color: var(--navy);
  font-size: 1.35rem;
}
[data-theme="dark"] .card-icon { color: #BEE3F8; }

/* ── Tags / pills ── */
.tag {
  display: inline-flex;
  align-items: center;
  width: fit-content;
  gap: 6px;
  border-radius: 999px;
  padding: 5px 10px;
  background: color-mix(in srgb, var(--emerald) 12%, transparent);
  color: var(--emerald);
  font-weight: 800;
  font-size: 0.78rem;
}
.pill-row { display: flex; flex-wrap: wrap; gap: 8px; }

/* ── Page transitions ── */
.page { display: none; }
.page.active { display: block; animation: fade 0.22s ease; }

@keyframes fade {
  from { opacity: 0; transform: translateY(6px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ── Page hero ── */
.page-hero {
  background:
    radial-gradient(circle at top right, color-mix(in srgb, var(--emerald) 18%, transparent), transparent 36%),
    linear-gradient(135deg, color-mix(in srgb, var(--navy) 8%, var(--surface)), var(--surface));
  border-bottom: 1px solid var(--border);
}
.page-hero .section { padding: 56px 0; }

/* ── Article layout ── */
.article-layout {
  display: grid;
  grid-template-columns: minmax(220px, 280px) minmax(0, 1fr);
  gap: 28px;
  align-items: start;
}

.side-nav {
  position: sticky;
  top: calc(var(--header-height) + 20px);
  display: grid;
  gap: 8px;
}
.side-nav button {
  text-align: left;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  padding: 11px 12px;
  border-radius: 12px;
  font-weight: 700;
}
.side-nav button.active,
.side-nav button:hover {
  border-color: var(--emerald);
  color: var(--emerald);
  box-shadow: var(--soft-shadow);
}

.article-content { display: grid; gap: 20px; }
.info-block ul, .info-block ol { margin: 10px 0 0; padding-left: 22px; }

/* ── Comparison ── */
.comparison {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

/* ── Table ── */
.table-wrap { overflow-x: auto; border-radius: var(--radius); border: 1px solid var(--border); }
table { width: 100%; border-collapse: collapse; background: var(--surface); min-width: 620px; }
th, td { padding: 14px 16px; border-bottom: 1px solid var(--border); text-align: left; }
th { color: var(--navy); font-family: "Montserrat", sans-serif; background: var(--surface-2); }
[data-theme="dark"] th { color: #D8ECFF; }

/* ── Filters ── */
.filters { display: flex; flex-wrap: wrap; gap: 10px; margin-bottom: 20px; }
.filter-btn {
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  border-radius: 999px;
  padding: 9px 13px;
  font-weight: 800;
}
.filter-btn.active, .filter-btn:hover {
  background: var(--emerald);
  color: white;
  border-color: var(--emerald);
}

/* ── Download meta ── */
.download-meta {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  align-items: center;
  margin-top: auto;
  color: var(--muted);
  font-size: 0.88rem;
  font-weight: 700;
}

/* ── Forum ── */
.forum-layout {
  display: grid;
  grid-template-columns: minmax(300px, 390px) minmax(0, 1fr);
  gap: 24px;
  align-items: start;
}

.form-grid { display: grid; gap: 12px; }
label { font-weight: 800; font-size: 0.92rem; }

input, textarea, select {
  width: 100%;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  border-radius: 12px;
  padding: 12px 13px;
  outline: none;
}
textarea { min-height: 122px; resize: vertical; }
input:focus, textarea:focus, select:focus {
  border-color: var(--emerald);
  box-shadow: var(--focus);
}

.post { display: grid; gap: 14px; }
.post-head {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: flex-start;
}
.post-meta { color: var(--muted); font-size: 0.9rem; }

.attachment-preview {
  display: none;
  max-height: 220px;
  width: 100%;
  object-fit: cover;
  border-radius: 14px;
  border: 1px solid var(--border);
}

.comment-box {
  background: var(--surface-2);
  border-radius: 14px;
  padding: 12px;
  display: grid;
  gap: 10px;
}
.comment, .reply {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 10px 12px;
  font-size: 0.95rem;
}
.reply { margin-left: 22px; }

/* ── Mobile panel ── */
.mobile-panel {
  display: none;
  position: fixed;
  inset: var(--header-height) 0 0;
  background: var(--surface);
  z-index: 90;
  overflow: auto;
  border-top: 1px solid var(--border);
  padding: 18px;
}
.mobile-panel.active { display: block; }
.mobile-search { display: none; margin-bottom: 16px; }

/* ── Accordion ── */
.accordion {
  border: 1px solid var(--border);
  border-radius: 16px;
  overflow: hidden;
  margin-bottom: 10px;
  background: var(--surface);
}
.accordion-trigger {
  width: 100%;
  border: 0;
  background: transparent;
  color: var(--text);
  padding: 15px;
  text-align: left;
  font-weight: 800;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.accordion-content { display: none; padding: 0 15px 15px; }
.accordion.open .accordion-content { display: grid; gap: 6px; }

/* ── Footer ── */
.footer { background: var(--navy); color: #EDF2F7; margin-top: 40px; }
.footer-inner {
  width: min(1220px, calc(100% - 32px));
  margin: 0 auto;
  padding: 42px 0;
  display: grid;
  gap: 18px;
}
.footer-row {
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 24px;
  padding: 24px 0;
  border-bottom: 1px solid rgba(255,255,255,0.16);
}
.footer-row:last-child { border-bottom: 0; }
.footer-label {
  font-family: "Montserrat", sans-serif;
  color: #9AE6B4;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-size: 0.84rem;
  font-weight: 800;
}
.expert-box {
  display: grid;
  grid-template-columns: 96px 1fr;
  gap: 18px;
  align-items: start;
}
.author-photo {
  width: 96px;
  height: 96px;
  border-radius: 24px;
  object-fit: cover;
  border: 2px solid rgba(255,255,255,0.2);
  display: block;
}
.footer a { color: #BEE3F8; font-weight: 800; }
.quick-links { display: grid; gap: 8px; }
.contact-line { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; }

/* ── Toast ── */
.toast {
  position: fixed;
  right: 18px;
  bottom: 18px;
  background: var(--navy);
  color: white;
  padding: 12px 14px;
  border-radius: 14px;
  box-shadow: var(--shadow);
  opacity: 0;
  transform: translateY(12px);
  pointer-events: none;
  transition: 0.2s ease;
  z-index: 999;
}
.toast.show { opacity: 1; transform: translateY(0); }

/* ── Responsive ── */
@media (max-width: 1040px) {
  .desktop-nav, .desktop-search { display: none; }
  .hamburger { display: inline-grid; }
  .header-inner { grid-template-columns: auto 1fr auto; }
  .mobile-search { display: block; }
  .hero { grid-template-columns: 1fr; }
  .grid-4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grid-3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .article-layout, .forum-layout { grid-template-columns: 1fr; }
  .side-nav { position: static; grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 700px) {
  :root { --header-height: 70px; }
  body { font-size: 16px; }
  .header-inner { width: min(100% - 22px, 1220px); gap: 10px; }
  .brand { font-size: 1.12rem; }
  .brand-mark { width: 38px; height: 38px; border-radius: 12px; }
  .hero, .section { width: min(100% - 24px, 1220px); }
  .hero { padding: 44px 0 28px; gap: 28px; }
  .section { padding: 52px 0; }
  .hero-panel { padding: 20px; border-radius: 24px; }
  .stats-grid, .grid-2, .grid-3, .grid-4, .comparison { grid-template-columns: 1fr; }
  .section-head { display: grid; }
  .side-nav { grid-template-columns: 1fr; }
  .post-head { display: grid; }
  .footer-row, .expert-box { grid-template-columns: 1fr; }
  .footer-inner { width: min(100% - 24px, 1220px); }
  .icon-btn { width: 42px; height: 42px; }
  .search-wrap { width: 100%; }
  .score-number { font-size: 3.4rem; }
}