:root {
  --bg: #f4f6f8;
  --surface: #ffffff;
  --surface-soft: #eef2f5;

  --text: #17212b;
  --muted: #65717e;

  --accent: #143d59;
  --accent-light: #1f5d85;

  --border: #dce3e8;

  --radius: 18px;
  --shadow: 0 18px 50px rgba(22, 35, 48, 0.08);

  --container: 1180px;
}


* {
  box-sizing: border-box;
}


html {
  scroll-behavior: smooth;
}


body {
  margin: 0;
  font-family:
    Inter,
    ui-sans-serif,
    system-ui,
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    sans-serif;

  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}


a {
  color: inherit;
}


.container {
  width: min(var(--container), calc(100% - 40px));
  margin: 0 auto;
}


/* HEADER */

.site-header {
  background: rgba(255, 255, 255, 0.94);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(12px);
}


.header-inner {
  min-height: 76px;

  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 30px;
}


.brand {
  display: flex;
  align-items: center;
  gap: 13px;
}


.brand-mark {
  width: 46px;
  height: 46px;

  display: grid;
  place-items: center;

  background: var(--accent);
  color: white;

  border-radius: 12px;

  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0.07em;
}


.brand strong,
.brand small {
  display: block;
}


.brand strong {
  font-size: 15px;
}


.brand small {
  color: var(--muted);
  margin-top: 2px;
}


.top-nav {
  display: flex;
  gap: 25px;
}


.top-nav a {
  text-decoration: none;
  color: var(--muted);
  font-size: 14px;
}


.top-nav a:hover {
  color: var(--accent);
}


/* HERO */

.hero {
  padding: 96px 0 82px;

  background:
    radial-gradient(
      circle at 85% 20%,
      rgba(31, 93, 133, 0.12),
      transparent 35%
    ),
    var(--bg);
}


.hero-grid {
  display: grid;
  grid-template-columns: 1.25fr 0.75fr;
  gap: 64px;
  align-items: center;
}


.eyebrow {
  display: inline-flex;
  align-items: center;

  color: var(--accent-light);

  font-size: 13px;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.12em;

  margin-bottom: 18px;
}


.hero h1 {
  font-size: clamp(44px, 6vw, 76px);
  line-height: 1.03;
  letter-spacing: -0.045em;

  margin: 0 0 26px;
}


.hero h1 span {
  display: block;
  color: var(--accent);
}


.hero-text {
  max-width: 720px;

  font-size: 19px;
  color: var(--muted);

  margin: 0;
}


.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;

  margin-top: 34px;
}


.button {
  display: inline-flex;
  justify-content: center;
  align-items: center;

  min-height: 48px;
  padding: 0 22px;

  border-radius: 12px;

  font-weight: 750;
  font-size: 15px;

  text-decoration: none;
}


.button.primary {
  background: var(--accent);
  color: white;
}


.button.secondary {
  background: white;
  border: 1px solid var(--border);
}


.hero-card {
  background: var(--surface);

  border: 1px solid var(--border);
  border-radius: var(--radius);

  padding: 34px;

  box-shadow: var(--shadow);
}


.hero-card-label {
  color: var(--accent-light);
  font-weight: 800;
  font-size: 12px;

  text-transform: uppercase;
  letter-spacing: 0.1em;

  margin-bottom: 12px;
}


.hero-card h2 {
  margin: 0 0 18px;

  line-height: 1.25;
  font-size: 27px;
}


.hero-card p {
  margin: 0;
  color: var(--muted);
}


/* SECTION */

.roadmap-section,
.assistant-section {
  padding: 92px 0;
}


.section-heading {
  max-width: 760px;
  margin-bottom: 50px;
}


.section-heading h2,
.assistant-section h2 {
  margin: 0 0 18px;

  font-size: clamp(34px, 4vw, 50px);
  line-height: 1.08;
  letter-spacing: -0.035em;
}


.section-heading p,
.assistant-section p {
  color: var(--muted);
  font-size: 18px;
}


/* STAGES */

.stages {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}


.stage-card {
  background: var(--surface);

  border: 1px solid var(--border);
  border-radius: 16px;

  padding: 25px;

  display: grid;
  grid-template-columns: 54px 1fr;
  gap: 20px;

  transition:
    transform 160ms ease,
    box-shadow 160ms ease,
    border-color 160ms ease;
}


.stage-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow);
  border-color: #b9c8d2;
}


.stage-number {
  width: 54px;
  height: 54px;

  display: grid;
  place-items: center;

  border-radius: 14px;

  background: var(--surface-soft);
  color: var(--accent);

  font-size: 17px;
  font-weight: 850;
}


.stage-content h3 {
  margin: 1px 0 7px;

  font-size: 20px;
  line-height: 1.25;
}


.stage-content p {
  margin: 0;
  color: var(--muted);
}


.stage-ai {
  grid-column: 2;

  margin-top: 4px;

  font-size: 13px;
  font-weight: 700;
  color: var(--accent-light);
}


/* AI */

.assistant-section {
  background: #e9eef2;
}


.assistant-grid {
  display: grid;
  grid-template-columns: 1fr 0.85fr;
  gap: 70px;
  align-items: center;
}


.assistant-examples {
  display: grid;
  gap: 10px;

  margin-top: 30px;
}


.example-question {
  background: rgba(255, 255, 255, 0.72);

  border: 1px solid rgba(255, 255, 255, 0.9);
  border-radius: 12px;

  padding: 13px 16px;

  font-size: 14px;
}


.assistant-card {
  background: var(--surface);

  border: 1px solid var(--border);
  border-radius: var(--radius);

  padding: 26px;

  box-shadow: var(--shadow);
}


.assistant-status {
  display: flex;
  justify-content: space-between;
  align-items: center;

  font-weight: 800;

  margin-bottom: 20px;
}


.assistant-status span {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.08em;

  background: var(--surface-soft);
  color: var(--muted);

  padding: 5px 9px;
  border-radius: 999px;
}


.chat-preview {
  display: grid;
  gap: 12px;

  margin-bottom: 20px;
}


.chat-message {
  padding: 13px 15px;

  border-radius: 12px;

  font-size: 14px;
}


.chat-message.user {
  background: var(--accent);
  color: white;

  margin-left: 35px;
}


.chat-message.assistant {
  background: var(--surface-soft);

  margin-right: 20px;
}


.assistant-button {
  width: 100%;
  min-height: 46px;

  border: 0;
  border-radius: 11px;

  background: #ccd5dc;
  color: #75818b;

  font-weight: 800;

  cursor: not-allowed;
}


.assistant-card small {
  display: block;

  margin-top: 10px;

  text-align: center;
  color: var(--muted);
}


/* FOOTER */

.site-footer {
  background: #17212b;
  color: #b9c3cb;

  padding: 35px 0;

  font-size: 14px;
}


/* LOADING */

.loading {
  color: var(--muted);

  padding: 25px;
  background: white;

  border-radius: 14px;
}


/* MOBILE */

@media (max-width: 850px) {

  .top-nav {
    display: none;
  }

  .hero {
    padding-top: 65px;
  }

  .hero-grid,
  .assistant-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .stages {
    grid-template-columns: 1fr;
  }

}


@media (max-width: 520px) {

  .container {
    width: min(100% - 28px, var(--container));
  }

  .brand small {
    display: none;
  }

  .hero h1 {
    font-size: 43px;
  }

  .hero-card {
    padding: 25px;
  }

  .stage-card {
    grid-template-columns: 44px 1fr;
    padding: 20px;
  }

  .stage-number {
    width: 44px;
    height: 44px;
  }

}

/* STAGE PAGE */

.stage-page-section {
  padding: 70px 0 95px;
}


.stage-back-link {
  display: inline-flex;
  margin-bottom: 28px;

  text-decoration: none;
  color: var(--accent-light);

  font-size: 14px;
  font-weight: 750;
}


.stage-page {
  max-width: 900px;
}


.stage-page-card {
  background: var(--surface);

  border: 1px solid var(--border);
  border-radius: var(--radius);

  padding: 38px;

  box-shadow: var(--shadow);
}


.stage-page-number {
  display: inline-flex;

  background: var(--surface-soft);
  color: var(--accent);

  border-radius: 10px;

  padding: 7px 11px;

  font-size: 13px;
  font-weight: 850;

  margin-bottom: 18px;
}


.stage-page-card h1 {
  margin: 0 0 18px;

  font-size: clamp(38px, 5vw, 58px);
  line-height: 1.06;
  letter-spacing: -0.04em;
}


.stage-page-description {
  margin: 0 0 34px;

  color: var(--muted);

  font-size: 19px;
}


.stage-block {
  margin-top: 32px;
}


.stage-block h2 {
  margin: 0 0 14px;

  font-size: 24px;
}


.stage-list {
  margin: 0;
  padding-left: 20px;
}


.stage-list li {
  margin-bottom: 9px;
}


.stage-ai-box {
  margin-top: 38px;

  background: #eef3f6;

  border: 1px solid var(--border);
  border-radius: 15px;

  padding: 24px;
}


.stage-ai-box h2 {
  margin-top: 0;
}


.stage-ai-button {
  display: inline-flex;

  margin-top: 10px;

  padding: 12px 18px;

  border: 0;
  border-radius: 10px;

  background: var(--accent);
  color: white;

  font-weight: 800;

  cursor: not-allowed;
}


.stage-next {
  margin-top: 35px;

  display: flex;
  justify-content: space-between;
  gap: 20px;

  flex-wrap: wrap;
}


.stage-next a {
  text-decoration: none;
  font-weight: 800;
  color: var(--accent);
}

.stage-content-paragraph {
  color: var(--text);
  font-size: 16px;
  line-height: 1.75;
  margin: 0 0 14px;
}

.stage-checklist {
  list-style: none;
  padding: 0;
  margin: 0;
}

.stage-checklist li {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  margin-bottom: 10px;
}

.check-box {
  color: var(--accent);
  font-weight: 800;
}

.review-note {
  margin-top: 32px;
  padding: 16px 18px;
  border-radius: 12px;
  background: #fff7e8;
  border: 1px solid #ead8ad;
  color: #6d5724;
  font-size: 14px;
  font-weight: 650;
}

/* HUMAN-FRIENDLY CONCEPT EXPLANATIONS */

.concepts-section {
  margin-top: 42px;
}

.concepts-section > h2 {
  margin-bottom: 22px;
}

.concept-card {
  background: #fbfcfd;
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 24px;
  margin-bottom: 20px;
}

.concept-card h3 {
  margin: 0 0 18px;
  font-size: 22px;
}

.concept-layer {
  border-radius: 12px;
  padding: 16px 18px;
  margin-top: 12px;
}

.concept-layer strong {
  display: block;
  margin-bottom: 7px;
  font-size: 14px;
}

.concept-layer p {
  margin: 0;
  line-height: 1.7;
}

.technical-layer {
  background: #f1f4f6;
}

.plain-layer {
  background: #eaf4fb;
  border: 1px solid #cfe2ef;
}

.owner-layer {
  background: #f5f6ed;
  border: 1px solid #dfe3c5;
}

.action-layer {
  background: #f7f1e8;
  border: 1px solid #e7d7bd;
}

.action-layer .stage-list {
  margin-top: 8px;
}

.concept-note {
  margin-top: 14px;
  padding: 14px 16px;
  border-left: 4px solid #b98729;
  background: #fff8e9;
  color: #674f1d;
  font-size: 14px;
  line-height: 1.6;
}

/* SOURCES */

.sources-section {
  margin-top: 46px;
  padding-top: 34px;
  border-top: 1px solid var(--border);
}

.sources-section > h2 {
  margin: 0 0 8px;
}

.sources-intro {
  margin: 0 0 22px;
  color: var(--muted);
}

.source-card {
  background: #f8fafb;
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 20px;
  margin-bottom: 14px;
}

.source-header {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  align-items: flex-start;
}

.source-header h3 {
  margin: 0;
  font-size: 17px;
  line-height: 1.35;
}

.source-verified {
  flex: 0 0 auto;
  font-size: 11px;
  color: var(--muted);
  background: white;
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 5px 8px;
}

.source-authority {
  margin: 8px 0 0;
  color: var(--muted);
  font-size: 14px;
}

.source-articles {
  margin: 15px 0 0;
  padding-left: 20px;
}

.source-articles li {
  margin-bottom: 7px;
  line-height: 1.6;
}

.source-link {
  display: inline-flex;
  margin-top: 14px;
  color: var(--accent);
  font-weight: 750;
  font-size: 14px;
  text-decoration: none;
}

.source-link:hover {
  text-decoration: underline;
}

@media (max-width: 620px) {
  .source-header {
    display: block;
  }

  .source-verified {
    display: inline-flex;
    margin-top: 8px;
  }
}

/* ILLUSTRATIONS */

.illustrations-section {
  margin-top: 46px;
  padding-top: 34px;
  border-top: 1px solid var(--border);
}

.illustrations-section > h2 {
  margin: 0 0 8px;
}

.illustrations-intro {
  margin: 0 0 22px;
  color: var(--muted);
}

.illustration-card {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 22px;
  align-items: stretch;

  background: #fbfcfd;
  border: 1px solid var(--border);
  border-radius: 14px;

  padding: 18px;
  margin-bottom: 16px;
}

.illustration-placeholder {
  min-height: 150px;

  display: grid;
  place-items: center;

  background:
    linear-gradient(
      135deg,
      #edf2f5,
      #f8fafb
    );

  border: 1px dashed #bcc9d2;
  border-radius: 12px;

  color: var(--muted);
  font-size: 13px;
  font-weight: 750;
  text-align: center;
  padding: 20px;
}

.illustration-content h3 {
  margin: 2px 0 10px;
  font-size: 19px;
}

.illustration-content p {
  margin: 0 0 12px;
  color: var(--text);
  line-height: 1.65;
}

.illustration-content small {
  color: var(--muted);
  line-height: 1.55;
}

@media (max-width: 700px) {
  .illustration-card {
    grid-template-columns: 1fr;
  }

  .illustration-placeholder {
    min-height: 180px;
  }
}

.illustration-image {
  width: 100%;
  height: 100%;
  min-height: 150px;
  object-fit: cover;
  border-radius: 12px;
  display: block;
  border: 1px solid var(--border);
}

/* IMAGE MODAL */

.illustration-image {
  cursor: zoom-in;
}

.image-modal {
  position: fixed;
  inset: 0;
  z-index: 9999;

  display: grid;
  place-items: center;

  padding: 30px;

  background: rgba(10, 18, 24, 0.88);
}

.image-modal-content {
  position: relative;

  width: min(1200px, 96vw);
  max-height: 92vh;

  display: flex;
  justify-content: center;
  align-items: center;
}

.image-modal-image {
  display: block;

  max-width: 100%;
  max-height: 88vh;

  width: auto;
  height: auto;

  border-radius: 14px;

  box-shadow:
    0 30px 90px rgba(0, 0, 0, 0.45);
}

.image-modal-close {
  position: absolute;
  top: -18px;
  right: -18px;

  width: 42px;
  height: 42px;

  border: 0;
  border-radius: 999px;

  background: white;
  color: #17212b;

  font-size: 30px;
  line-height: 1;

  cursor: pointer;

  box-shadow:
    0 8px 30px rgba(0, 0, 0, 0.28);
}

.image-modal-close:hover {
  transform: scale(1.04);
}

@media (max-width: 700px) {
  .image-modal {
    padding: 14px;
  }

  .image-modal-close {
    top: -10px;
    right: -6px;
  }
}

/* VERIFIED RULES */

.verified-rules-layer {
  background: #edf7ef;
  border: 1px solid #cfe2d2;
}

.verified-rules-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin-top: 12px;
}

.verified-rule-card {
  background: white;
  border: 1px solid #dbe7dd;
  border-radius: 10px;
  padding: 14px;
}

.verified-rule-card > strong {
  display: block;
  margin-bottom: 6px;
}

.verified-rule-distance {
  display: block;
  font-size: 16px;
  font-weight: 800;
  color: var(--accent);
  margin-bottom: 8px;
}

.verified-rule-card small {
  display: block;
  color: var(--muted);
  line-height: 1.45;
}

@media (max-width: 700px) {
  .verified-rules-grid {
    grid-template-columns: 1fr;
  }
}