/* ===== CSS VARIABLES ===== */
:root {
  --primary-color: #2563eb;
  --text-primary: #363636;
  --text-secondary: #6b7280;
  --text-muted: #9ca3af;
  --surface: #ffffff;
  --surface-secondary: #f9fafb;
  --border: #e5e7eb;
  --border-light: #f3f4f6;

  /* Typography Variables */
  --font-size-hero: 3.5rem;
  --font-size-hero-subtitle: 1.5rem;
  --font-size-section-title: 1.8rem;
  --font-size-large: 1.25rem;
  --font-size-base: 1rem;
  --font-size-small: 0.9rem;
  --font-size-xs: 0.85rem;

  /* Mobile Typography Variables */
  --font-size-hero-mobile: 2.2rem;
  --font-size-hero-subtitle-mobile: 1.2rem;
  --font-size-section-title-mobile: 1.4rem;
  --font-size-large-mobile: 1.1rem;
  --font-size-base-mobile: 0.95rem;
  --font-size-small-mobile: 0.85rem;
  --font-size-xs-mobile: 0.8rem;

  /* Spacing Variables */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;
}

/* ===== GLOBAL RESET & BASE STYLES ===== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  -webkit-font-smoothing: antialiased;
  letter-spacing: 0.2px;
  font-family: "Inter", sans-serif;
  line-height: 1.6;
  color: var(--text-primary);
  background: #fafbfc;
  padding-bottom: 2rem;
  font-size: var(--font-size-base);
}

.container {
  max-width: 1100px;
  margin: 0 auto;
}

/* ===== SECTION CONSISTENCY ===== */
section {
  padding: var(--spacing-lg) 0;
}

.section-header {
  text-align: center;
  margin-bottom: var(--spacing-xl);
}

.section-title {
  font-size: var(--font-size-section-title);
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: var(--spacing-xs);
}


/* ===== HERO SECTION ===== */
.hero {
  padding: var(--spacing-xl) var(--spacing-sm);
  background: var(--surface);
  text-align: center;
}

.venue-badge {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.7em;
  width: auto;
  margin: var(--spacing-sm) auto var(--spacing-md);
  color: var(--primary-color);
}

.venue-badge .venue-name {
  font-family: "Source Serif 4", Georgia, serif;
  color: var(--text-primary);
  font-size: 1.4rem;
  font-style: italic;
  font-weight: 400;
  letter-spacing: 0.2px;
  white-space: nowrap;
}

.venue-badge .venue-rule {
  width: 48px;
  height: 1px;
  background: linear-gradient(
    90deg,
    transparent,
    var(--border)
  );
}

.venue-badge .venue-rule:last-child {
  background: linear-gradient(90deg, var(--border), transparent);
}

.venue-badge i,
.venue-badge svg {
  width: 1.1em;
  height: 1.1em;
  color: #2563eb;
}

.hero h1 {
  font-size: var(--font-size-hero);
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: var(--spacing-md);
  line-height: 1.1;
}

.hero-subtitle {
  font-size: var(--font-size-hero-subtitle);
  font-weight: 400;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-md);
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
  line-height: 1.4;
  word-break: keep-all;
  overflow-wrap: normal;
}

/* ===== AUTHORS & AFFILIATIONS ===== */
.authors {
  margin-bottom: var(--spacing-xl);
}

.author-list {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: var(--spacing-xs);
  margin-bottom: var(--spacing-sm);
  font-size: 1.1rem;
}

.author {
  color: var(--text-primary);
  font-weight: 500;
}

.author:not(:last-child)::after {
  content: "";
  margin-right: var(--spacing-xs);
}

.author sup {
  font-size: 0.65em;
  vertical-align: super;
  opacity: 0.9;
  margin-left: 2px;
}

.author a {
  text-decoration: none;
}

.affiliations {
  display: flex;
  justify-content: center;
  gap: 2em;
  flex-wrap: wrap;
  margin-bottom: var(--spacing-sm);
}

.affiliations span {
  white-space: nowrap;
  font-size: var(--font-size-small);
  vertical-align: middle;
}

.affiliations sup {
  margin-right: 0.2em;
  font-size: 0.8em;
  vertical-align: super;
}

.affiliation {
  font-size: var(--font-size-base);
  color: var(--text-secondary);
  margin-top: var(--spacing-xs);
}

/* ===== BUTTONS ===== */
.btn-group {
  display: flex;
  justify-content: center;
  gap: var(--spacing-sm);
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-xs);
  padding: 0.75rem var(--spacing-md);
  background: var(--surface);
  border: 1.5px solid var(--border);
  color: var(--text-primary);
  text-decoration: none;
  border-radius: 8px;
  font-weight: 500;
  font-size: 0.95rem;
  transition: all 0.2s ease;
  min-height: 44px;
}

.btn:hover {
  border-color: var(--primary-color);
  color: var(--primary-color);
}

.btn-primary {
  background: var(--primary-color);
  color: white;
  border-color: var(--primary-color);
}

.btn-primary:hover {
  background: #1d4ed8;
  border-color: #1d4ed8;
  color: white;
}

.copy-btn {
  position: absolute;
  top: 0.6rem;
  right: 0.6rem;
  background: transparent;
  color: var(--text-secondary);
  border: none;
  padding: 0.4rem;
  border-radius: 6px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s ease;
  line-height: 1;
}

.copy-btn svg {
  width: 1.25rem;
  height: 1.25rem;
}

.copy-btn:hover {
  color: var(--primary-color);
}

/* ===== KEY FEATURES SECTION ===== */
.key-features {
  border-radius: 12px;
  padding: 0 var(--spacing-sm);
  color: #2c3e50;
  max-width: 700px;
  margin: 0 auto var(--spacing-sm);
  border: 1.5px solid rgba(255, 255, 255, 0.3);
}

.key-features .section-title {
  font-weight: 700;
  margin-bottom: var(--spacing-md);
  text-align: center;
  color: #1a252f;
}

.features-list {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1rem;
}

.feature-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 0.4rem;
  padding: 0.75rem 1rem;
}

.feature-item {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
}

.feature-icon {
  font-size: 1.9rem;
  line-height: 1;
  color: var(--primary-color);
  display: flex;
  align-items: center;
  justify-content: center;
}

.feature-icon svg {
  width: 1.75rem;
  height: 1.75rem;
  stroke-width: 1.6;
}

.feature-item h3 {
  font-size: 0.88rem;
  font-weight: 600;
  margin: 0;
  color: var(--text-primary);
  letter-spacing: 0.01em;
}

.feature-item p {
  font-size: 0.72rem;
  margin: 0;
  color: var(--text-secondary);
  line-height: 1.4;
  font-style: normal;
}

.feature-item p strong {
  font-weight: 400;
}

/* ===== ARCHITECTURE SECTION ===== */
.architecture {
  background: var(--surface-secondary);
  border-top: 1px solid var(--border-light);
}

.architecture-visual {
  text-align: center;
}

.architecture-image {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
  border-radius: 8px;
}

.architecture-placeholder {
  box-sizing: border-box;
  width: 100%;
  max-width: 900px;
  height: 580px;
  padding: 10px 0;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto;
}

.architecture > img {
  width: 100%;
  height: auto;
  max-height: 100%;
  display: block;
}

.architecture-placeholder i {
  font-size: 3rem;
  color: var(--text-muted);
}

/* ===== ABSTRACT SECTION ===== */
.abstract {
  background-color: var(--surface-light);
  border-radius: 8px;
}

.abstract-content {
  max-width: 680px;
  margin: 0 auto;
  padding: 0 var(--spacing-sm);
  font-size: 1.15rem;
  line-height: 1.85;
  color: var(--text-secondary);
  text-align: center;
  letter-spacing: 0.01em;
}

.abstract-content em {
  color: var(--text-primary);
  font-style: normal;
  font-weight: 600;
}

.abstract-content p {
  margin-bottom: var(--spacing-md);
  max-width: 45em;
}

/* ===== TEXT TO SPEECH PROCESS SECTION ===== */
.process-section {
  max-width: 700px;
  margin: 0 auto;
}

.process-card {
  background: var(--surface);
  border: 1px solid var(--border);
  padding: var(--spacing-lg);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
  max-width: 800px;
  margin: 0 auto;
}

.process-step {
  margin-bottom: 2.5rem;
}

.process-step:last-child {
  margin-bottom: 0;
}

.step-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: var(--spacing-sm);
}

.step-number {
  background: var(--primary-color);
  color: white;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.875rem;
  font-weight: 600;
}

.step-title {
  font-size: var(--font-size-large);
  font-weight: 600;
  color: var(--text-primary);
}

.step-content {
  background: var(--surface-secondary);
  border: 1px solid var(--border-light);
  border-radius: 8px;
  padding: var(--spacing-md);
  margin-bottom: 0.75rem;
}

.step-caption {
  font-size: var(--font-size-base);
  color: var(--text-secondary);
  text-align: center;
  font-style: italic;
}

.audio-container {
  text-align: center;
}

.audio-player {
  width: 100%;
  max-width: 300px;
  margin: 0 auto;
  display: block;
  height: 40px;
  border-radius: 6px;
}

/* ===== AUDIO SAMPLES SECTION ===== */
.audio-samples {
  background: var(--surface-secondary);
  border-top: 1px solid var(--border-light);
}

.samples-grid {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 2.5rem;
  margin-top: var(--spacing-xl);
  width: 700px;
  margin: auto;
}

.sample-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: var(--spacing-lg);
  min-width: 300px;
  width: 100%;
}

.sample-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--spacing-md);
  padding-bottom: var(--spacing-sm);
  border-bottom: 1px solid var(--border-light);
}

.sample-title {
  font-size: var(--font-size-large);
  font-weight: 600;
  color: var(--text-primary);
}

.sample-type {
  padding: 0.4rem 0.8rem;
  background: var(--surface-secondary);
  color: var(--text-secondary);
  border-radius: 6px;
  font-size: var(--font-size-xs);
  font-weight: 500;
  border: 1px solid var(--border);
}

.audio-controls {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-sm);
}

.audio-item {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xs);
}

.audio-label {
  font-size: var(--font-size-small);
  font-weight: 500;
  color: var(--text-secondary);
}

audio {
  width: 100%;
  min-width: 100px;
  height: 40px;
}

/* ===== TEXT STYLES ===== */
.hebrew-text {
  font-size: 1.2rem;
  font-weight: 500;
  direction: rtl;
  text-align: right;
  background: var(--surface-secondary);
  border-radius: 8px;
  color: var(--text-primary);
}

.ipa-text {
  font-family: "Noto Sans", sans-serif;
  font-size: 1.1rem;
  color: var(--text-primary);
  direction: ltr;
  text-align: left;
  margin-bottom: 0;
}

/* ===== COMPARISON TABLE SECTION ===== */
.comparison {
  background: var(--surface);
}

.comparison-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: var(--spacing-xl);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
}

.comparison-table th {
  background: var(--surface-secondary);
  color: var(--text-primary);
  padding: 1.2rem var(--spacing-sm);
  font-weight: 600;
  text-align: center;
  border-bottom: 1px solid var(--border);
}

.comparison-table td {
  padding: 1.2rem var(--spacing-sm);
  border-bottom: 1px solid var(--border-light);
  text-align: center;
  vertical-align: middle;
}

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

.method-ours {
  background: #f0f9ff;
  font-weight: 600;
}

/* ===== MORE CONTENT SECTION ===== */
.more-content {
  background: var(--surface);
}

.inline-link {
  color: var(--primary-color);
  text-decoration: none;
  font-weight: 500;
  border-bottom: 1px solid transparent;
  transition: all 0.2s ease;
}

.inline-link:hover {
  border-bottom-color: var(--primary-color);
}

/* ===== CITATION SECTION ===== */
.citation {
  background: var(--surface-secondary);
  border-top: 1px solid var(--border-light);
}

.citation-box {
  background: var(--surface);
  color: var(--text-primary);
  padding: var(--spacing-lg);
  border-radius: 12px;
  border: 1px solid var(--border);
  box-shadow: 0 2px 16px rgba(26, 23, 34, 0.04);
  font-family: "JetBrains Mono", monospace;
  font-size: var(--font-size-small);
  line-height: 1.6;
  overflow-x: auto;
  position: relative;
}

.citation-box pre {
  background: transparent;
  color: var(--text-primary);
  margin: 0;
}

.citation-box pre code.hljs {
  background: transparent;
  color: var(--text-primary);
  padding: 0;
  font-family: "JetBrains Mono", monospace;
  font-size: var(--font-size-small);
  line-height: 1.75;
  tab-size: 2;
}

.citation-box .hljs-keyword {
  color: #6d28d9;
  font-weight: 600;
}

.citation-box .hljs-symbol {
  color: #0369a1;
  font-weight: 500;
}

.citation-box .hljs-attr {
  color: #b45309;
  font-weight: 500;
}

.citation-box .hljs-string {
  color: #047857;
}

.citation-box .hljs-punctuation {
  color: var(--text-muted);
}

/* ===== FOOTER ===== */
.footer {
  background: var(--surface-secondary);
  border-top: 1px solid var(--border-light);
  padding: var(--spacing-lg) 0;
  margin-top: var(--spacing-xl);
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.footer-left .copyright {
  color: var(--text-secondary);
  font-size: var(--font-size-small);
  margin: 0;
}

.footer-venue {
  color: var(--text-muted);
  font-size: var(--font-size-xs);
  margin: 0.25rem 0 0;
}

.footer-nav {
  margin-top: var(--spacing-xs);
}

.footer-nav-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: var(--font-size-xs);
  font-weight: 500;
  transition: color 0.2s ease;
  border-bottom: 1px solid transparent;
}

.footer-nav-link:hover {
  color: var(--primary-color);
  border-bottom-color: var(--primary-color);
}

.footer-links {
  display: flex;
  gap: var(--spacing-md);
}

.footer-link {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  background: var(--surface);
  color: var(--text-secondary);
  text-decoration: none;
  border-radius: 8px;
  font-size: 1.2rem;
  transition: all 0.3s ease;
  border: 1px solid var(--border);
}

.footer-link:hover {
  color: var(--primary-color);
  border-color: var(--primary-color);
}

.footer-link img {
  width: 24px;
  height: 24px;
  object-fit: contain;
}

/* Mobile scroll button - hidden by default */
.mobile-scroll-btn {
  display: none;
  position: absolute;
  bottom: 4rem;
  left: 50%;
  transform: translateX(-50%);
  z-index: 10;
}

.scroll-down-btn {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: var(--primary-color);
  color: var(--surface);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  transition: all 0.3s ease;
  border: none;
}

.scroll-down-btn:active {
  transform: scale(0.95);
}

/* ===== MOBILE RESPONSIVE DESIGN ===== */
@media (max-width: 768px) {
  .features-list {
    grid-template-columns: repeat(2, 1fr);
  }

  body {
    font-size: var(--font-size-base-mobile);
  }

  .section-title {
    font-size: var(--font-size-section-title-mobile);
  }

  .hero {
    padding: var(--spacing-lg) var(--spacing-sm);
  }

  .hero h1 {
    font-size: var(--font-size-hero-mobile);
  }

  .hero-subtitle {
    font-size: var(--font-size-hero-subtitle-mobile);
  }

  .step-title {
    font-size: var(--font-size-large-mobile);
  }

  .sample-title {
    font-size: var(--font-size-large-mobile);
  }

  .container {
    padding: 0 var(--spacing-sm);
  }

  .author-list {
    flex-direction: column;
    gap: 0.25rem;
    font-size: var(--font-size-base-mobile);
  }

  .author:not(:last-child)::after {
    content: "";
    margin-right: 0;
  }

  .affiliations {
    flex-direction: column;
    align-items: center;
    gap: 0.3rem;
    margin: var(--spacing-xs) auto var(--spacing-lg);
    text-align: center;
  }

  .affiliations span {
    font-size: var(--font-size-xs-mobile);
  }

  .btn-group {
    flex-direction: column;
    align-items: center;
    gap: 0.75rem;
  }

  .btn {
    width: 200px;
    justify-content: center;
    font-size: var(--font-size-small-mobile);
  }

  .comparison-table {
    font-size: var(--font-size-xs-mobile);
    display: block;
    overflow-x: auto;
    white-space: nowrap;
  }

  .comparison-table th,
  .comparison-table td {
    padding: 0.8rem var(--spacing-xs);
    font-size: var(--font-size-xs-mobile);
    white-space: normal;
    min-width: 120px;
  }

  .comparison-table audio {
    width: 100% !important;
    max-width: 240px;
    height: auto !important;
    min-height: 40px !important;
    display: inline-block !important;
  }

  .sample-header {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--spacing-xs);
  }

  .process-section {
    padding: var(--spacing-xl) var(--spacing-sm);
  }

  .process-card {
    padding: var(--spacing-md);
  }

  .step-title {
    font-size: var(--font-size-large-mobile);
  }

  .hebrew-text {
    font-size: var(--font-size-base-mobile);
  }

  .ipa-text {
    font-size: var(--font-size-base-mobile);
  }

  .feature-item h3 {
    font-size: var(--font-size-base-mobile);
  }

  .feature-item p {
    font-size: var(--font-size-small-mobile);
  }

  .abstract-content {
    font-size: var(--font-size-base-mobile);
    padding: 0 var(--spacing-xs);
  }

  .citation-box {
    font-size: var(--font-size-xs-mobile);
  }

  .audio-label {
    font-size: var(--font-size-xs-mobile);
  }

  .footer-content {
    flex-direction: column;
    gap: var(--spacing-md);
    text-align: center;
  }

  .footer-left .copyright {
    font-size: var(--font-size-xs-mobile);
  }

  .footer-links {
    gap: var(--spacing-sm);
  }

  .footer-link {
    width: 36px;
    height: 36px;
    font-size: 1rem;
  }
}

/* Show only on mobile */
@media screen and (max-width: 768px) and (min-width: 375px) and (min-height: 850px) {
  .mobile-scroll-btn {
    display: block;
  }

  /* Make hero position relative to contain the absolute button */
  .hero {
    position: relative;
  }
}

@media (max-width: 600px) {
  .hero {
    padding: var(--spacing-lg) var(--spacing-sm) var(--spacing-md);
  }
  
  /* Only apply full-height hero to main index page */
  .hero.main-hero {
    min-height: 100vh;
    padding: var(--spacing-xl) var(--spacing-sm) 1rem;
  }

  .btn {
    flex: 1 1 100%;
    justify-content: center;
    padding: 0.6rem var(--spacing-sm);
    font-size: var(--font-size-small-mobile);
    min-height: 44px;
  }

  .btn-group {
    gap: 0.75rem;
    justify-content: stretch;
  }

  .architecture {
    padding: 1rem 0;
  }

  .architecture-placeholder {
    max-width: 90vw;
    height: auto;
    padding: 10px 5px;
  }

  .abstract {
    padding: var(--spacing-sm) var(--spacing-sm);
  }

  .abstract-content {
    max-width: 100%;
    font-size: var(--font-size-base-mobile);
    line-height: 1.5;
    padding: 0 var(--spacing-xs);
  }

  .abstract-content p {
    margin-bottom: var(--spacing-sm);
  }
}

@media (max-width: 480px) {
  .key-features {
    padding: 0;
    max-width: calc(100% - 2rem);
    margin-left: auto;
    margin-right: auto;
    border: 1.5px solid rgba(255, 255, 255, 0.4);
  }

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

  .feature-item {
    padding: 1rem;
  }

  .feature-icon {
    font-size: 1.6rem;
  }

  .feature-icon svg {
    width: 1.6rem;
    height: 1.6rem;
  }

  .feature-item h3 {
    font-size: var(--font-size-small-mobile);
  }

  .feature-item p {
    font-size: var(--font-size-xs-mobile);
  }

  .mobile-scroll-btn {
    bottom: var(--spacing-xl);
  }

  .scroll-down-btn {
    width: 48px;
    height: 48px;
    font-size: var(--font-size-base-mobile);
  }
}

.caption {
  font-weight: 300;
  font-size: 0.7em;
  color: #666; /* optional for even lighter look */
}

.emoji {
  vertical-align: middle;
  padding: 3px;
  font-size: clamp(16px, 2.5vw, 22px);
}

td.hebrew-text {
  background: transparent;
  border: none;
  padding: 1rem;
  text-align: center;
}