/* Reset and base styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --color-text: #111827;
  --color-text-secondary: #4b5563;
  --color-text-muted: #6b7280;
  --color-bg: #ffffff;
  --color-bg-alt: #f3f4f6;
  --color-surface: #f8fafc;
  --color-border: #e5e7eb;
  --color-accent: #1f3a7a;
  --color-accent-soft: #e8edf7;
  --color-link: #1f3a7a;
  --color-link-hover: #162a59;
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2.5rem;
  --spacing-xl: 4rem;
  --spacing-2xl: 6rem;
  --max-width: 960px;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
  line-height: 1.75;
  color: var(--color-text);
  background: var(--color-bg-alt);
  min-height: 100vh;
  padding: var(--spacing-xl) var(--spacing-md);
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  background: var(--color-bg);
  border-radius: 16px;
  padding: var(--spacing-2xl);
  box-shadow: 0 24px 70px rgba(17, 24, 39, 0.08);
  position: relative;
}

/* Header */
.header {
  margin-bottom: var(--spacing-lg);
  padding-bottom: var(--spacing-md);
  border-bottom: 1px solid var(--color-border);
  text-align: left;
}

.portrait-wrapper {
  display: flex;
  justify-content: flex-start;
  margin-bottom: var(--spacing-sm);
}

.portrait {
  width: 160px;
  height: 160px;
  object-fit: cover;
  border-radius: 50%;
  border: 3px solid var(--color-border);
  box-shadow: 0 12px 28px rgba(17, 24, 39, 0.12);
}

.header-title-wrapper {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-xs);
}

.app-icon {
  width: 64px;
  height: 64px;
  border-radius: 12px;
  flex-shrink: 0;
  box-shadow: 0 4px 12px rgba(17, 24, 39, 0.1);
}

.title {
  font-size: 2.4rem;
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: -0.02em;
  margin: 0;
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
}

.header-credit {
  font-size: 14px;
  line-height: 1.5;
  color: var(--color-text-secondary);
  margin: 0 0 var(--spacing-sm) 0;
}

.header-description {
  font-size: 17px;
  line-height: 1.75;
  color: var(--color-text);
  margin: 0;
  margin-top: var(--spacing-xs);
}

.header-links {
  margin-top: var(--spacing-sm);
  font-size: 15px;
}

.header-links a {
  color: var(--color-link);
  text-decoration: none;
  font-weight: 500;
}

/* Header links */
.header-links {
  margin-top: var(--spacing-sm);
}

.header-links-list {
  list-style: none;
  display: flex;
  flex-direction: row;
  flex-wrap: wrap;
  gap: var(--spacing-xs);
  justify-content: flex-start;
  margin: 0;
  padding: 0;
}

.header-links-list li {
  margin: 0;
}

.header-link-item {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  color: var(--color-link);
  text-decoration: none;
  font-size: 15px;
  transition: all 0.18s ease;
  border: 1px solid transparent;
  padding: 0;
  border-radius: 999px;
  background: rgba(31, 58, 122, 0.05);
}

.header-link-item .link-icon-img {
  width: 24px;
  height: 24px;
  display: block;
  background: transparent;
}

.header-link-item:hover {
  color: var(--color-link-hover);
  background: rgba(31, 58, 122, 0.08);
  border-color: rgba(31, 58, 122, 0.2);
  box-shadow: 0 6px 16px rgba(17, 24, 39, 0.08);
}

/* Modal */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(17, 24, 39, 0.45);
  display: grid;
  place-items: center;
  padding: var(--spacing-lg);
  z-index: 1000;
}

.modal-overlay[hidden] {
  display: none !important;
}

.modal-dialog {
  background: #ffffff;
  border-radius: 12px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.18);
  max-width: 400px;
  width: 100%;
  padding: var(--spacing-md);
  border: 1px solid rgba(0, 0, 0, 0.04);
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-sm);
}

.modal-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: -0.01em;
}

.modal-close {
  border: 1px solid rgba(0, 0, 0, 0.08);
  background: #f9fafb;
  border-radius: 50%;
  width: 32px;
  height: 32px;
  font-size: 18px;
  line-height: 1;
  cursor: pointer;
  transition: all 0.18s ease;
}

.modal-close:hover {
  background: #eef2f7;
}

.modal-body {
  margin-top: var(--spacing-xs);
}

.modal-email {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: 0.01em;
  word-break: break-word;
}

.layout {
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) 0.95fr;
  gap: var(--spacing-lg);
  align-items: start;
}

.identity-panel {
  display: flex;
  justify-content: flex-start;
  position: relative;
}

/* Identity Card */
.identity-card {
  width: 100%;
  max-width: 320px;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xs);
  padding: var(--spacing-md) var(--spacing-lg);
  background: linear-gradient(145deg, #f8fafc 0%, #eef2f7 100%);
  border: 1px solid rgba(0, 0, 0, 0.05);
  border-radius: 14px;
  box-shadow: 0 16px 40px rgba(17, 24, 39, 0.09);
  position: sticky;
  top: var(--spacing-lg);
  right: 0;
}

.identity-item {
  display: flex;
  align-items: center;
  gap: 0;
  padding: 0.4rem 0;
  border-bottom: 1px solid rgba(0, 0, 0, 0.08);
}

.identity-item:last-child {
  border-bottom: none;
}

.identity-label {
  font-size: 14.5px;
  font-weight: 600;
  color: var(--color-text);
  letter-spacing: 0.005em;
  text-align: left;
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
}

.portfolio {
  margin-top: var(--spacing-md);
  padding-top: var(--spacing-sm);
}

.portfolio-title {
  font-size: 13px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-xs);
}

.portfolio-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.portfolio-list a {
  color: var(--color-text);
  text-decoration: none;
  border-bottom: 1px solid rgba(0, 0, 0, 0.08);
  padding-bottom: 0.25rem;
}

.portfolio-list a:hover {
  color: var(--color-link-hover);
  border-bottom-color: var(--color-link-hover);
}

/* Modal */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(17, 24, 39, 0.35);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-md);
  backdrop-filter: blur(2px);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.15s ease;
}

.modal-backdrop.open {
  opacity: 1;
  pointer-events: auto;
}

.modal {
  max-width: 380px;
  width: 100%;
  border-radius: 14px;
  background: var(--color-bg);
  box-shadow: 0 22px 70px rgba(17, 24, 39, 0.14);
  padding: var(--spacing-lg);
  border: 1px solid rgba(0, 0, 0, 0.04);
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-sm);
}

.modal-title {
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin: 0;
}

.modal-close {
  border: none;
  background: transparent;
  font-size: 1.25rem;
  line-height: 1;
  cursor: pointer;
  color: var(--color-text);
}

.modal-body {
  margin-top: var(--spacing-xs);
}

.modal-email-row {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  flex-wrap: wrap;
}

.modal-email {
  margin: 0;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.01em;
  word-break: break-all;
}

.email-copy {
  border: 1px solid rgba(31, 58, 122, 0.2);
  background: rgba(31, 58, 122, 0.14);
  color: var(--color-link);
  border-radius: 6px;
  padding: 0.25rem 0.7rem;
  font-size: 13px;
  cursor: pointer;
  transition: all 0.18s ease;
}

.email-copy:hover {
  background: rgba(31, 58, 122, 0.2);
  border-color: rgba(31, 58, 122, 0.3);
}

/* Content sections */
.content {
  margin-bottom: var(--spacing-xl);
}

.section {
  margin-bottom: var(--spacing-lg);
}

.section-title {
  font-size: 1rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-xs);
  font-weight: 600;
}

.section p {
  font-size: 17px;
  line-height: 1.85;
  color: var(--color-text);
  margin-bottom: 0;
}

.lead {
  font-size: 18px;
  font-weight: 400;
  color: var(--color-text);
  margin-bottom: 0;
  line-height: 1.85;
}

strong {
  font-weight: 600;
  color: var(--color-text);
}

/* Links */
a {
  color: var(--color-link);
  text-decoration: underline;
  text-decoration-color: var(--color-border);
  text-underline-offset: 3px;
  transition: color 0.2s ease, text-decoration-color 0.2s ease;
  font-weight: 400;
}

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


/* Responsive design */
@media (max-width: 768px) {
  body {
    padding: var(--spacing-lg) var(--spacing-md);
    font-size: 16px;
  }

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

  .layout {
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
  }

  .identity-panel {
    justify-content: center;
  }

  .portrait {
    width: 160px;
    height: 160px;
  }

  .title {
    font-size: 2rem;
  }

  .app-icon {
    width: 48px;
    height: 48px;
  }

  .header-title-wrapper {
    gap: var(--spacing-xs);
  }

  .lead {
    font-size: 17px;
  }

  .intro p,
  .bio p,
  .research p {
    font-size: 16px;
  }

  .header {
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-lg);
  }

  .content {
    margin-bottom: var(--spacing-lg);
  }

  .header-links-list {
    flex-direction: column;
    align-items: center;
  }

  .identity-card {
    position: relative;
    top: auto;
    right: auto;
    max-width: 100%;
    flex-direction: column;
    gap: var(--spacing-xs);
    margin: var(--spacing-md) 0 0 0;
    padding: 0;
  }

  .identity-item {
    width: 100%;
    justify-content: center;
    padding: 0.3rem 0;
  }

  .portfolio {
    margin-top: var(--spacing-sm);
    padding-top: var(--spacing-sm);
  }

  .identity-label {
    font-size: 13px;
  }

  .identity-divider {
    width: 40px;
    height: 1px;
    margin: 0.35rem 0;
  }
}

@media (max-width: 480px) {
  body {
    padding: var(--spacing-md) var(--spacing-sm);
  }

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

  .layout {
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
  }

  .identity-panel {
    justify-content: center;
  }

  .portrait {
    width: 140px;
    height: 140px;
  }

  .title {
    font-size: 1.75rem;
  }

  .app-icon {
    width: 40px;
    height: 40px;
  }

  .identity-card {
    position: relative;
    top: auto;
    right: auto;
    max-width: 100%;
    flex-direction: column;
    gap: 0.35rem;
    margin: var(--spacing-sm) 0 0 0;
    padding: 0;
  }

  .identity-label {
    font-size: 12px;
  }

  .identity-item {
    padding: 0.25rem 0;
  }

  .identity-divider {
    width: 25px;
    height: 1px;
    margin: 0.25rem 0;
  }

  .portfolio {
    margin-top: var(--spacing-xs);
    padding-top: var(--spacing-xs);
  }
}

/* Download buttons */
.download-buttons {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
  margin-top: var(--spacing-md);
  margin-bottom: var(--spacing-lg);
}

.download-button {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-sm) var(--spacing-md);
  background: linear-gradient(145deg, #f8fafc 0%, #eef2f7 100%);
  border: 1px solid rgba(31, 58, 122, 0.15);
  border-radius: 12px;
  text-decoration: none;
  color: var(--color-text);
  transition: all 0.2s ease;
  box-shadow: 0 4px 12px rgba(17, 24, 39, 0.06);
}

.download-button:hover:not(.disabled) {
  background: linear-gradient(145deg, #eef2f7 0%, #e2e8f0 100%);
  border-color: rgba(31, 58, 122, 0.25);
  box-shadow: 0 8px 20px rgba(17, 24, 39, 0.12);
  transform: translateY(-2px);
  color: var(--color-link-hover);
}

.download-button.disabled {
  opacity: 0.6;
  cursor: not-allowed;
  background: linear-gradient(145deg, #f0f0f0 0%, #e5e5e5 100%);
  border-color: rgba(0, 0, 0, 0.1);
}

.download-button.disabled.download-button-linux {
  pointer-events: none;
}

.download-button.disabled .download-platform {
  color: var(--color-text-secondary);
}

.download-icon {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
  display: block;
}

.download-text {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
}

.download-label {
  font-size: 13px;
  color: var(--color-text-secondary);
  font-weight: 500;
  letter-spacing: 0.02em;
}

.download-platform {
  font-size: 16px;
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: -0.01em;
}

.download-version {
  font-size: 12px;
  font-weight: 500;
  color: var(--color-text-secondary);
  margin-left: 0.25rem;
}

.download-button:hover .download-platform {
  color: var(--color-link-hover);
}

@media (min-width: 481px) {
  .download-buttons {
    flex-direction: row;
    gap: var(--spacing-md);
  }

  .download-button {
    flex: 1;
  }
}

/* Video section */
.video-section {
  margin-bottom: var(--spacing-lg);
}

.demo-video {
  width: 100%;
  max-width: 100%;
  height: auto;
  border-radius: 12px;
  box-shadow: 0 8px 24px rgba(17, 24, 39, 0.12);
  background: var(--color-bg-alt);
}

/* Image section */
.image-section {
  margin-bottom: var(--spacing-lg);
}

.demo-image {
  width: 100%;
  max-width: 100%;
  height: auto;
  display: block;
  border-radius: 12px;
  box-shadow: 0 8px 24px rgba(17, 24, 39, 0.12);
  background: var(--color-bg-alt);
}