/* ==========================================================================
   ZhengMa — Computer Systems Design & Integrated Systems
   Primary stylesheet (homepage + secondary pages)
   Dark copper-bronze theme
   ========================================================================== */

:root {
  --bg: #141110;
  --bg-soft: #1B1613;
  --surface: #201A15;
  --surface-2: #2A221B;
  --cream: #E8DCC8;
  --text: #F3ECE3;
  --text-soft: #CBBBA3;
  --text-faint: #A8957C;
  --copper: #C77B3F;
  --copper-light: #E09A5F;
  --copper-bright: #E9A96B;
  --umber: #6B4423;
  --umber-deep: #3E2814;
  --rule: #332A21;
  --rule-copper: #8A5A30;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-size: 16px;
  font-family: "Segoe UI", "Helvetica Neue", Arial, sans-serif;
  background-color: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

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

a {
  color: var(--copper-light);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--copper-bright);
}

.container {
  width: 100%;
  max-width: 1160px;
  margin: 0 auto;
  padding: 0 24px;
}

h1, h2, h3, h4, h5, h6 {
  line-height: 1.2;
  font-weight: 700;
  color: var(--cream);
}

/* ==========================================================================
   HEADER — centered wordmark
   ========================================================================== */

.center-wordmark {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--surface);
  border-bottom: 1px solid var(--rule);
}

.center-wordmark .wordmark-row {
  text-align: center;
  padding: 22px 24px 14px;
}

.center-wordmark .brand {
  display: inline-block;
  font-size: 2.25rem;
  font-weight: 800;
  letter-spacing: 0.02em;
  color: var(--copper);
  line-height: 1;
}

.center-wordmark .brand:hover {
  color: var(--copper-bright);
}

.center-wordmark .nav-row {
  text-align: center;
  padding-bottom: 14px;
}

.center-wordmark .nav-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px 28px;
  list-style: none;
}

.center-wordmark .nav-links a {
  font-size: 0.9rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--text-soft);
  padding: 6px 2px;
}

.center-wordmark .nav-links a:hover,
.center-wordmark .nav-links a.active {
  color: var(--copper-light);
}

.center-wordmark .nav-divider {
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--rule-copper), transparent);
}

.nav-toggle {
  display: none;
  position: absolute;
  top: 20px;
  right: 20px;
  background: none;
  border: 1px solid var(--rule-copper);
  border-radius: 6px;
  color: var(--cream);
  font-size: 1.5rem;
  line-height: 1;
  width: 44px;
  height: 40px;
  cursor: pointer;
}

.nav-toggle:hover {
  border-color: var(--copper);
}

/* ==========================================================================
   HERO — backdrop with diagonal stripes
   ========================================================================== */

.backdrop-hero {
  position: relative;
  background-color: var(--bg);
  background-image: repeating-linear-gradient(45deg, rgba(199,123,63,0.10) 0 2px, transparent 2px 26px);
  border-bottom: 1px solid var(--rule);
}

.backdrop-hero .hero-inner {
  max-width: 1160px;
  margin: 0 auto;
  padding: 96px 24px 104px;
}

.backdrop-hero .eyebrow {
  display: inline-block;
  background-color: var(--copper);
  color: var(--cream);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  padding: 7px 16px;
  border-radius: 999px;
}

.backdrop-hero h1 {
  font-size: clamp(2.3rem, 5vw, 4rem);
  font-weight: 800;
  color: var(--cream);
  max-width: 820px;
  margin: 26px 0 20px;
  letter-spacing: -0.01em;
}

.backdrop-hero .hero-sub {
  font-size: 1.15rem;
  color: var(--text-soft);
  max-width: 640px;
  margin-bottom: 38px;
}

.hero-ctas {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}

.btn {
  display: inline-block;
  font-weight: 700;
  font-size: 0.95rem;
  letter-spacing: 0.03em;
  padding: 15px 30px;
  border-radius: 8px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.15s ease, background-color 0.2s ease, border-color 0.2s ease;
}

.btn:hover {
  transform: translateY(-2px);
}

.btn-primary {
  background-color: var(--copper);
  color: var(--cream);
}

.btn-primary:hover {
  background-color: var(--copper-light);
  color: var(--bg);
}

.btn-outline {
  background-color: transparent;
  color: var(--cream);
  border-color: var(--cream);
}

.btn-outline:hover {
  background-color: var(--cream);
  color: var(--bg);
}

/* ==========================================================================
   STATEMENT ROW
   ========================================================================== */

.statement-row {
  background-color: var(--bg);
  border-bottom: 1px solid var(--rule);
}

.statement-row .container {
  padding-top: 84px;
  padding-bottom: 84px;
}

.statement-row p {
  font-size: clamp(1.5rem, 3vw, 2.3rem);
  font-weight: 700;
  line-height: 1.35;
  color: var(--cream);
  max-width: 1000px;
}

.statement-row p .copper {
  color: var(--copper-light);
}

/* ==========================================================================
   SOLID SERVICE TILES
   ========================================================================== */

.tile-grid {
  background-color: var(--bg-soft);
  border-bottom: 1px solid var(--rule);
}

.tile-grid .container {
  padding-top: 88px;
  padding-bottom: 88px;
}

.section-head {
  max-width: 720px;
  margin-bottom: 48px;
}

.section-head .kicker {
  display: block;
  color: var(--copper-light);
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  margin-bottom: 12px;
}

.section-head h2 {
  font-size: clamp(1.7rem, 3.2vw, 2.5rem);
  margin-bottom: 14px;
}

.section-head p {
  color: var(--text-soft);
  font-size: 1.05rem;
}

.tiles {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}

.tile {
  border-radius: 12px;
  padding: 34px 30px;
  min-height: 190px;
  display: flex;
  flex-direction: column;
  justify-content: flex-start;
}

.tile .tile-num {
  font-size: 0.8rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  margin-bottom: 16px;
}

.tile h3 {
  font-size: 1.3rem;
  margin-bottom: 12px;
}

.tile p {
  font-size: 0.98rem;
  line-height: 1.6;
}

.tile-copper {
  background-color: var(--copper);
  color: var(--cream);
}

.tile-copper .tile-num,
.tile-copper h3 {
  color: var(--cream);
}

.tile-copper p {
  color: #F7EFE4;
}

.tile-dark {
  background-color: var(--surface);
  color: var(--cream);
}

.tile-dark .tile-num,
.tile-dark h3 {
  color: var(--cream);
}

.tile-dark p {
  color: var(--text-soft);
}

.tile-cream {
  background-color: var(--cream);
  color: var(--umber-deep);
}

.tile-cream .tile-num,
.tile-cream h3 {
  color: var(--umber-deep);
}

.tile-cream p {
  color: #4A3318;
}

/* ==========================================================================
   MILESTONE CARDS
   ========================================================================== */

.milestones {
  background-color: var(--bg);
  border-bottom: 1px solid var(--rule);
}

.milestones .container {
  padding-top: 88px;
  padding-bottom: 88px;
}

.milestone-track {
  position: relative;
  padding-top: 28px;
  margin-top: 20px;
}

.milestone-track::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, var(--rule-copper), var(--copper), var(--rule-copper));
}

.milestone-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.milestone-card {
  position: relative;
}

.milestone-card .dot {
  position: absolute;
  top: -33px;
  left: 0;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  background-color: var(--copper);
  color: var(--cream);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 0.95rem;
  border: 4px solid var(--bg);
}

.milestone-card h3 {
  font-size: 1.2rem;
  color: var(--cream);
  margin-bottom: 10px;
}

.milestone-card p {
  font-size: 0.95rem;
  color: var(--text-soft);
}

/* ==========================================================================
   FAQ ACCORDION
   ========================================================================== */

.faq-section {
  background-color: var(--bg-soft);
  border-bottom: 1px solid var(--rule);
}

.faq-section .container {
  padding-top: 88px;
  padding-bottom: 88px;
}

.faq-wrap {
  max-width: 860px;
}

.faq-item {
  border: 1px solid var(--rule);
  border-radius: 10px;
  margin-bottom: 14px;
  background-color: var(--surface);
  overflow: hidden;
}

.faq-item.open {
  border-color: var(--rule-copper);
}

.faq-question {
  width: 100%;
  background: none;
  border: none;
  cursor: pointer;
  text-align: left;
  color: var(--cream);
  font-size: 1.08rem;
  font-weight: 700;
  padding: 22px 56px 22px 24px;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.faq-question .faq-icon {
  flex-shrink: 0;
  font-size: 1.4rem;
  color: var(--copper-light);
  font-weight: 800;
  transition: transform 0.25s ease;
}

.faq-item.open .faq-question .faq-icon {
  transform: rotate(45deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
}

.faq-item.open .faq-answer {
  max-height: 320px;
}

.faq-answer p {
  color: var(--text-soft);
  padding: 0 24px 24px;
  font-size: 0.98rem;
}

/* ==========================================================================
   CTA BAND
   ========================================================================== */

.cta-band {
  background-color: var(--copper);
}

.cta-band .container {
  padding-top: 72px;
  padding-bottom: 72px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
}

.cta-band h2 {
  color: var(--umber-deep);
  font-size: clamp(1.6rem, 3vw, 2.3rem);
  margin-bottom: 10px;
}

.cta-band p {
  color: #4A3318;
  font-size: 1.05rem;
  max-width: 560px;
}

.cta-band .btn-dark {
  background-color: var(--umber-deep);
  color: var(--cream);
}

.cta-band .btn-dark:hover {
  background-color: var(--bg);
  color: var(--cream);
}

/* ==========================================================================
   FOOTER — symmetric two-column
   ========================================================================== */

.duo-footer {
  background-color: var(--surface);
  border-top: 1px solid var(--rule);
}

.duo-footer .footer-main {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  padding-top: 64px;
  padding-bottom: 64px;
}

.duo-footer .footer-brand h3 {
  font-size: 1.4rem;
  color: var(--copper);
  margin-bottom: 14px;
}

.duo-footer .footer-brand p {
  color: var(--text-soft);
  font-size: 0.95rem;
  margin-bottom: 10px;
}

.duo-footer .footer-contact {
  margin-top: 14px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.duo-footer .footer-contact a,
.duo-footer .footer-contact span {
  color: var(--copper-light);
  font-size: 0.95rem;
}

.duo-footer .footer-contact .addr {
  color: var(--text-faint);
}

.duo-footer .footer-col-group {
  display: flex;
  flex-direction: column;
  gap: 32px;
}

.duo-footer .footer-links h4 {
  font-size: 0.82rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-faint);
  margin-bottom: 14px;
}

.duo-footer .footer-links ul {
  list-style: none;
}

.duo-footer .footer-links li {
  margin-bottom: 9px;
}

.duo-footer .footer-links a {
  color: var(--text-soft);
  font-size: 0.95rem;
}

.duo-footer .footer-links a:hover {
  color: var(--copper-light);
}

.duo-footer .footer-rule {
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--rule-copper), transparent);
}

.duo-footer .footer-bottom {
  padding-top: 22px;
  padding-bottom: 22px;
  text-align: center;
}

.duo-footer .footer-bottom p {
  color: var(--text-faint);
  font-size: 0.85rem;
}

/* ==========================================================================
   SECONDARY PAGE SHARED (services / contact)
   ========================================================================== */

.page-hero {
  background-color: var(--bg);
  background-image: repeating-linear-gradient(45deg, rgba(199,123,63,0.08) 0 2px, transparent 2px 26px);
  border-bottom: 1px solid var(--rule);
}

.page-hero .container {
  padding-top: 80px;
  padding-bottom: 72px;
}

.page-hero .eyebrow {
  display: inline-block;
  background-color: var(--copper);
  color: var(--cream);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  padding: 7px 16px;
  border-radius: 999px;
}

.page-hero h1 {
  font-size: clamp(2rem, 4vw, 3rem);
  margin-top: 24px;
  margin-bottom: 16px;
}

.page-hero p {
  color: var(--text-soft);
  font-size: 1.1rem;
  max-width: 680px;
}

.content-section {
  background-color: var(--bg-soft);
  border-bottom: 1px solid var(--rule);
}

.content-section .container {
  padding-top: 72px;
  padding-bottom: 72px;
}

/* service detail cards */
.service-detail {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
}

.service-detail-card {
  background-color: var(--surface);
  border: 1px solid var(--rule);
  border-left: 4px solid var(--copper);
  border-radius: 10px;
  padding: 32px 34px;
}

.service-detail-card h2 {
  font-size: 1.5rem;
  color: var(--cream);
  margin-bottom: 14px;
}

.service-detail-card h2 .num {
  color: var(--copper-light);
  margin-right: 8px;
}

.service-detail-card p {
  color: var(--text-soft);
  font-size: 1rem;
  margin-bottom: 12px;
}

/* process */
.process-list {
  list-style: none;
  counter-reset: proc;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}

.process-list li {
  background-color: var(--surface);
  border: 1px solid var(--rule);
  border-radius: 10px;
  padding: 28px;
  position: relative;
}

.process-list li::before {
  counter-increment: proc;
  content: counter(proc, decimal-leading-zero);
  display: block;
  font-size: 1rem;
  font-weight: 800;
  color: var(--copper-light);
  letter-spacing: 0.1em;
  margin-bottom: 12px;
}

.process-list li h3 {
  font-size: 1.15rem;
  color: var(--cream);
  margin-bottom: 10px;
}

.process-list li p {
  color: var(--text-soft);
  font-size: 0.95rem;
}

/* contact */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 44px;
  align-items: start;
}

.contact-info-block {
  background-color: var(--surface);
  border: 1px solid var(--rule);
  border-radius: 12px;
  padding: 32px;
}

.contact-info-block h2 {
  font-size: 1.4rem;
  margin-bottom: 20px;
}

.contact-line {
  margin-bottom: 18px;
}

.contact-line .label {
  display: block;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--copper-light);
  margin-bottom: 6px;
}

.contact-line .value {
  color: var(--cream);
  font-size: 1.02rem;
}

.contact-line .value.muted {
  color: var(--text-soft);
}

.contact-form {
  background-color: var(--surface);
  border: 1px solid var(--rule);
  border-radius: 12px;
  padding: 32px;
}

.contact-form h2 {
  font-size: 1.4rem;
  margin-bottom: 22px;
}

.form-group {
  margin-bottom: 18px;
}

.form-group label {
  display: block;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-soft);
  margin-bottom: 7px;
}

.form-group input,
.form-group textarea {
  width: 100%;
  background-color: var(--bg);
  border: 1px solid var(--rule);
  border-radius: 8px;
  color: var(--text);
  font-size: 1rem;
  font-family: inherit;
  padding: 13px 15px;
  transition: border-color 0.2s ease;
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--copper);
}

.form-group textarea {
  min-height: 130px;
  resize: vertical;
}

.form-note {
  font-size: 0.85rem;
  color: var(--text-faint);
  margin-top: 14px;
}

.form-success {
  display: none;
  background-color: var(--umber-deep);
  border: 1px solid var(--copper);
  color: var(--cream);
  border-radius: 8px;
  padding: 14px 18px;
  margin-top: 16px;
  font-size: 0.95rem;
}

/* small FAQ on contact page */
.contact-faq .faq-wrap {
  max-width: 100%;
}

/* ==========================================================================
   SCROLL REVEAL
   ========================================================================== */

.fade-up {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

.fade-up.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ==========================================================================
   RESPONSIVE
   ========================================================================== */

@media (max-width: 900px) {
  .tiles {
    grid-template-columns: repeat(2, 1fr);
  }

  .milestone-row {
    grid-template-columns: repeat(2, 1fr);
    gap: 36px 24px;
  }

  .process-list {
    grid-template-columns: 1fr;
  }

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

@media (max-width: 680px) {
  .center-wordmark {
    position: sticky;
  }

  .center-wordmark .wordmark-row {
    padding: 16px 24px 12px;
  }

  .center-wordmark .brand {
    font-size: 1.7rem;
  }

  .nav-toggle {
    display: block;
  }

  .center-wordmark .nav-row {
    padding-bottom: 0;
  }

  .center-wordmark .nav-links {
    display: none;
    flex-direction: column;
    gap: 0;
    padding-bottom: 16px;
  }

  .center-wordmark .nav-links.open {
    display: flex;
  }

  .center-wordmark .nav-links a {
    padding: 12px 0;
    font-size: 0.95rem;
  }

  .center-wordmark .nav-divider {
    display: none;
  }

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

  .milestone-row {
    grid-template-columns: 1fr;
  }

  .duo-footer .footer-main {
    grid-template-columns: 1fr;
    gap: 36px;
  }

  .backdrop-hero .hero-inner {
    padding: 72px 24px 80px;
  }
}