/* ==========================================================================
   SSOne Support Center (ssone-jc.mom)
   Style: 35 | 滚动产品长廊 (Black & White Minimalism / Keynote Launch Style)
   ========================================================================== */

:root {
  --bg-primary: #09090b;
  --bg-secondary: #121215;
  --bg-elevated: #18181b;
  --bg-card: #141417;
  --bg-card-hover: #1c1c20;
  
  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-strong: rgba(255, 255, 255, 0.18);
  --border-focus: #ffffff;
  
  --text-primary: #f4f4f5;
  --text-secondary: #a1a1aa;
  --text-muted: #71717a;
  --text-highlight: #ffffff;

  --accent-white: #ffffff;
  --accent-gray: #27272a;
  
  --font-sans: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
  
  --container-max: 1200px;
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-full: 9999px;
  
  --transition-fast: 0.18s cubic-bezier(0.16, 1, 0.3, 1);
  --transition-normal: 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  line-height: 1.65;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
}

a {
  color: var(--text-primary);
  text-decoration: none;
  transition: color var(--transition-fast), border-color var(--transition-fast);
}

a:hover {
  color: var(--text-highlight);
}

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

/* --------------------------------------------------------------------------
   Layout & Container
   -------------------------------------------------------------------------- */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-left: auto;
  margin-right: auto;
  padding-left: 20px;
  padding-right: 20px;
}

.section {
  padding: 80px 0;
  position: relative;
}

.section-hero {
  padding: 100px 0 60px;
}

@media (max-width: 768px) {
  .section {
    padding: 56px 0;
  }
  .section-hero {
    padding: 70px 0 40px;
  }
}

/* --------------------------------------------------------------------------
   Header & Sticky Nav
   -------------------------------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(9, 9, 11, 0.82);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-subtle);
  transition: border-color var(--transition-fast);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}

.brand-link {
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand-logo-img {
  height: 38px;
  width: auto;
}

.nav-desktop {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav-link {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color var(--transition-fast);
}

.nav-link:hover, .nav-link.active {
  color: var(--text-highlight);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 14px;
}

.btn-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: #ffffff;
  color: #09090b !important;
  font-weight: 600;
  font-size: 13.5px;
  padding: 9px 18px;
  border-radius: var(--radius-full);
  border: 1px solid #ffffff;
  transition: transform var(--transition-fast), background-color var(--transition-fast), box-shadow var(--transition-fast);
  white-space: nowrap;
}

.btn-cta:hover {
  background: #e4e4e7;
  transform: translateY(-1px);
  box-shadow: 0 4px 14px rgba(255, 255, 255, 0.16);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: transparent;
  color: var(--text-primary);
  font-weight: 500;
  font-size: 13.5px;
  padding: 9px 18px;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-strong);
  transition: background var(--transition-fast), border-color var(--transition-fast);
  white-space: nowrap;
}

.btn-secondary:hover {
  background: var(--bg-elevated);
  border-color: #ffffff;
}

/* Mobile Toggle */
.mobile-toggle {
  display: none;
  background: none;
  border: 1px solid var(--border-subtle);
  color: var(--text-primary);
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  align-items: center;
  justify-content: center;
}

.mobile-menu-drawer {
  display: none;
  position: fixed;
  top: 68px;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(9, 9, 11, 0.98);
  backdrop-filter: blur(20px);
  z-index: 99;
  flex-direction: column;
  padding: 30px 24px;
  gap: 20px;
  overflow-y: auto;
}

.mobile-menu-drawer.open {
  display: flex;
}

.mobile-menu-drawer .nav-link {
  font-size: 18px;
  padding: 10px 0;
  border-bottom: 1px solid var(--border-subtle);
}

@media (max-width: 900px) {
  .nav-desktop {
    display: none;
  }
  .mobile-toggle {
    display: flex;
  }
}

/* --------------------------------------------------------------------------
   Typography & Keynote Polish
   -------------------------------------------------------------------------- */
.badge-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-secondary);
  background: var(--bg-elevated);
  border: 1px solid var(--border-subtle);
  padding: 4px 10px;
  border-radius: var(--radius-full);
}

.badge-tag .dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: #ffffff;
}

.hero-headline {
  font-size: clamp(2.2rem, 5.2vw, 4.2rem);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.04em;
  color: #ffffff;
  margin: 18px 0 20px;
}

.hero-headline span {
  color: var(--text-muted);
}

.hero-subhead {
  font-size: clamp(1.05rem, 1.8vw, 1.3rem);
  line-height: 1.6;
  color: var(--text-secondary);
  max-width: 760px;
  margin-bottom: 32px;
}

.hero-cta-group {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 40px;
}

.hero-disclaimer-note {
  font-size: 12.5px;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 8px;
}

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

.section-head.center {
  text-align: center;
  max-width: 760px;
  margin-left: auto;
  margin-right: auto;
}

.section-title {
  font-size: clamp(1.8rem, 3.2vw, 2.6rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  color: #ffffff;
  margin-top: 10px;
  margin-bottom: 12px;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* --------------------------------------------------------------------------
   Quick Diagnostic Gateway (问题快速入口)
   -------------------------------------------------------------------------- */
.diag-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 20px;
}

.diag-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 24px;
  transition: border-color var(--transition-fast), transform var(--transition-fast), background var(--transition-fast);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.diag-card:hover {
  border-color: var(--border-strong);
  background: var(--bg-card-hover);
  transform: translateY(-2px);
}

.diag-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
}

.diag-badge {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--text-muted);
  letter-spacing: 0.05em;
}

.diag-card-title {
  font-size: 18px;
  font-weight: 600;
  color: #ffffff;
  margin-bottom: 8px;
}

.diag-card-desc {
  font-size: 13.5px;
  color: var(--text-secondary);
  line-height: 1.55;
  margin-bottom: 16px;
}

.diag-card-link {
  font-size: 13px;
  font-weight: 600;
  color: #ffffff;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.diag-card-link svg {
  transition: transform var(--transition-fast);
}

.diag-card:hover .diag-card-link svg {
  transform: translateX(4px);
}

/* --------------------------------------------------------------------------
   Diagnostic Stepper (连接排查流程)
   -------------------------------------------------------------------------- */
.stepper-container {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  position: relative;
}

@media (max-width: 992px) {
  .stepper-container {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 560px) {
  .stepper-container {
    grid-template-columns: 1fr;
  }
}

.step-box {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 24px;
  position: relative;
  display: flex;
  flex-direction: column;
}

.step-num {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  color: #ffffff;
  background: var(--bg-elevated);
  border: 1px solid var(--border-strong);
  width: 36px;
  height: 36px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
}

.step-title {
  font-size: 17px;
  font-weight: 600;
  color: #ffffff;
  margin-bottom: 8px;
}

.step-text {
  font-size: 13.5px;
  color: var(--text-secondary);
  line-height: 1.55;
  margin-bottom: 14px;
  flex-grow: 1;
}

.step-highlight {
  font-family: var(--font-mono);
  font-size: 11.5px;
  background: rgba(255, 255, 255, 0.04);
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  border-left: 2px solid #ffffff;
}

/* --------------------------------------------------------------------------
   Comparison Table & Matrix
   -------------------------------------------------------------------------- */
.table-responsive {
  width: 100%;
  overflow-x: auto;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  background: var(--bg-card);
  margin: 24px 0;
}

.custom-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 14px;
  min-width: 640px;
}

.custom-table th {
  background: var(--bg-elevated);
  color: #ffffff;
  font-weight: 600;
  padding: 14px 18px;
  border-bottom: 1px solid var(--border-subtle);
  white-space: nowrap;
}

.custom-table td {
  padding: 14px 18px;
  border-bottom: 1px solid var(--border-subtle);
  color: var(--text-secondary);
}

.custom-table tr:last-child td {
  border-bottom: none;
}

.custom-table tr:hover td {
  background: rgba(255, 255, 255, 0.02);
  color: var(--text-primary);
}

/* --------------------------------------------------------------------------
   Security Checklist (账号安全清单)
   -------------------------------------------------------------------------- */
.security-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 20px;
}

.security-item {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 22px;
  display: flex;
  gap: 16px;
}

.security-icon {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
  color: #ffffff;
}

.security-content h4 {
  font-size: 16px;
  font-weight: 600;
  color: #ffffff;
  margin-bottom: 6px;
}

.security-content p {
  font-size: 13.5px;
  color: var(--text-secondary);
  line-height: 1.55;
}

/* --------------------------------------------------------------------------
   Interactive Problem Selector (Widget)
   -------------------------------------------------------------------------- */
.interactive-diag-box {
  background: var(--bg-secondary);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  padding: 32px;
  margin: 36px 0;
}

.diag-selector-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 24px;
}

.diag-btn {
  background: var(--bg-card);
  color: var(--text-secondary);
  border: 1px solid var(--border-subtle);
  padding: 8px 16px;
  border-radius: var(--radius-full);
  font-size: 13.5px;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.diag-btn:hover, .diag-btn.active {
  background: #ffffff;
  color: #09090b;
  border-color: #ffffff;
}

.diag-result-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 24px;
  display: none;
}

.diag-result-card.active {
  display: block;
}

.diag-result-card h4 {
  font-size: 18px;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 12px;
}

.diag-result-card ol {
  padding-left: 20px;
  color: var(--text-secondary);
  font-size: 14px;
  line-height: 1.7;
  margin-bottom: 16px;
}

/* --------------------------------------------------------------------------
   Articles Grid & Cards
   -------------------------------------------------------------------------- */
.articles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 24px;
}

.article-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 28px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: border-color var(--transition-fast), transform var(--transition-fast);
}

.article-card:hover {
  border-color: var(--border-strong);
  transform: translateY(-2px);
}

.article-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 12px;
  color: var(--text-muted);
  font-family: var(--font-mono);
  margin-bottom: 14px;
}

.article-card-title {
  font-size: 19px;
  font-weight: 700;
  color: #ffffff;
  line-height: 1.4;
  margin-bottom: 10px;
}

.article-card-excerpt {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 20px;
  flex-grow: 1;
}

.article-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 16px;
  border-top: 1px solid var(--border-subtle);
}

/* --------------------------------------------------------------------------
   Article Detail Page Layout
   -------------------------------------------------------------------------- */
.article-header {
  padding: 40px 0 30px;
  border-bottom: 1px solid var(--border-subtle);
  margin-bottom: 40px;
}

.breadcrumbs {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 18px;
  flex-wrap: wrap;
}

.breadcrumbs a {
  color: var(--text-secondary);
}

.breadcrumbs a:hover {
  color: #ffffff;
}

.article-title {
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.03em;
  color: #ffffff;
  margin-bottom: 18px;
}

.article-info-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 20px;
  font-size: 13px;
  color: var(--text-secondary);
  font-family: var(--font-mono);
}

.article-layout {
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 48px;
  align-items: start;
}

@media (max-width: 900px) {
  .article-layout {
    grid-template-columns: 1fr;
  }
}

.toc-sidebar {
  position: sticky;
  top: 96px;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 20px;
}

.toc-title {
  font-size: 13px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  margin-bottom: 12px;
}

.toc-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.toc-list li a {
  font-size: 13.5px;
  color: var(--text-secondary);
  line-height: 1.4;
  display: block;
}

.toc-list li a:hover {
  color: #ffffff;
  text-decoration: underline;
}

.article-content {
  font-size: 16px;
  line-height: 1.8;
  color: #d4d4d8;
}

.article-content h2 {
  font-size: clamp(1.4rem, 2.4vw, 1.9rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  color: #ffffff;
  margin-top: 48px;
  margin-bottom: 18px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-subtle);
}

.article-content h3 {
  font-size: 1.25rem;
  font-weight: 600;
  color: #f4f4f5;
  margin-top: 32px;
  margin-bottom: 14px;
}

.article-content p {
  margin-bottom: 20px;
}

.article-content ul, .article-content ol {
  margin-bottom: 24px;
  padding-left: 24px;
}

.article-content li {
  margin-bottom: 8px;
}

.callout-box {
  background: var(--bg-card);
  border-left: 3px solid #ffffff;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  padding: 18px 22px;
  margin: 28px 0;
  font-size: 14.5px;
  color: var(--text-primary);
}

.callout-box strong {
  color: #ffffff;
}

.article-faq-section {
  margin-top: 60px;
  padding-top: 40px;
  border-top: 1px solid var(--border-subtle);
}

.related-articles {
  margin-top: 50px;
  padding: 28px;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
}

.related-articles h4 {
  font-size: 17px;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 16px;
}

.related-links-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.related-links-list a {
  color: var(--text-secondary);
  font-size: 14.5px;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.related-links-list a:hover {
  color: #ffffff;
  text-decoration: underline;
}

/* --------------------------------------------------------------------------
   Accordion (FAQ)
   -------------------------------------------------------------------------- */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color var(--transition-fast);
}

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

.faq-question {
  width: 100%;
  text-align: left;
  background: none;
  border: none;
  padding: 20px 24px;
  color: #ffffff;
  font-size: 16px;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  gap: 16px;
}

.faq-icon {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
  transition: transform var(--transition-fast);
}

.faq-item.open .faq-icon {
  transform: rotate(180deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition-normal);
  padding: 0 24px;
  color: var(--text-secondary);
  font-size: 14.5px;
  line-height: 1.65;
}

.faq-item.open .faq-answer {
  max-height: 500px;
  padding-bottom: 22px;
}

/* --------------------------------------------------------------------------
   User Feedback Section (用户反馈 / 提交使用体验)
   -------------------------------------------------------------------------- */
.feedback-box {
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 40px;
  max-width: 760px;
  margin: 0 auto;
}

.feedback-form {
  display: flex;
  flex-direction: column;
  gap: 18px;
  margin-top: 24px;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.form-label {
  font-size: 13.5px;
  font-weight: 500;
  color: var(--text-primary);
}

.form-input, .form-textarea, .form-select {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 12px 16px;
  color: #ffffff;
  font-family: inherit;
  font-size: 14px;
  outline: none;
  transition: border-color var(--transition-fast);
}

.form-input:focus, .form-textarea:focus, .form-select:focus {
  border-color: #ffffff;
}

.form-textarea {
  min-height: 110px;
  resize: vertical;
}

.feedback-disclaimer {
  font-size: 12px;
  color: var(--text-muted);
  line-height: 1.5;
}

/* --------------------------------------------------------------------------
   Footer
   -------------------------------------------------------------------------- */
.site-footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-subtle);
  padding: 70px 0 36px;
  margin-top: auto;
}

.footer-top {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 50px;
}

@media (max-width: 900px) {
  .footer-top {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 560px) {
  .footer-top {
    grid-template-columns: 1fr;
  }
}

.footer-brand p {
  color: var(--text-secondary);
  font-size: 13.5px;
  line-height: 1.6;
  max-width: 320px;
  margin-top: 14px;
}

.footer-col h4 {
  font-size: 13px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: #ffffff;
  margin-bottom: 16px;
}

.footer-nav {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-nav a {
  font-size: 13.5px;
  color: var(--text-secondary);
}

.footer-nav a:hover {
  color: #ffffff;
}

.footer-bottom {
  padding-top: 28px;
  border-top: 1px solid var(--border-subtle);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  font-size: 12.5px;
  color: var(--text-muted);
}

.footer-disclaimer-bar {
  margin-top: 20px;
  padding: 14px 18px;
  background: rgba(255, 255, 255, 0.02);
  border-radius: var(--radius-sm);
  font-size: 11.5px;
  line-height: 1.5;
  color: var(--text-muted);
}

/* --------------------------------------------------------------------------
   Mobile Tuning (320px, 375px, 390px)
   -------------------------------------------------------------------------- */
@media (max-width: 480px) {
  .container {
    padding-left: 16px;
    padding-right: 16px;
  }
  .hero-cta-group {
    flex-direction: column;
    align-items: stretch;
  }
  .btn-cta, .btn-secondary {
    width: 100%;
  }
  .feedback-box {
    padding: 24px 18px;
  }
  .diag-card, .step-box, .article-card {
    padding: 20px;
  }
}