:root {
    --blue-main: #3b6fd8;
    --blue-middle: #ece6f9;
    --blue-soft: #e8f0ff;
    --gray-900: #1f2937;
    --gray-700: #4b5563;
    --gray-500: #6b7280;
    --gray-300: #d1d5db;
    --gray-200: #e5e7eb;
    --gray-100: #f3f4f6;

    --purple-main: #7c6fd6;    /* muted lavender */
    --purple-soft: #f2f1fb;    /* very light lavender */
    --btn-border: #d6d9f0;
    --bg: #ffffff;
    --card-border: #e6e8ef;

    --bib-code-fg: #5f6b2d;
  }
  
  .dark-mode {
    --bg: #0f1220;
    --card-border: #23264a;
  
    --text-main: #e5e7eb;
    --text-sub: #9ca3af;
  
    --blue-main: #8aa2ff;
    --blue-soft: rgba(138,162,255,0.12);
  
    --purple-main: #a79bff;
    --purple-soft: rgba(167,155,255,0.10);
  
    --btn-border: #2f3363;

    --bib-code-fg: #d4dcaa;
  }
  
  .paper-item {
    display: flex;
    gap: 18px;
    padding: 20px;
    border-radius: 16px;
    /* background: #f6fbf8; */
    /* border: 1px solid #d7efe3; */
    background: var(--bg);
    align-items:flex-start;
  } 

  .paper-thumb {
    width: 200px;
    flex-shrink: 0;
  }
  
  .paper-thumb img {
    width: 100%;
    height: 100%;
    aspect-ratio: 4 / 3;
    border-radius: 12px;
    object-fit: cover;
    background: #eef3ff;
    border: 1px solid var(--gray-200);
  }
  
  .paper-content {
    flex: 1;
    min-width: 0;
  }
  .paper-title {
    font-size: 1.05em;
    font-weight: 600;
    color: var(--gray-900);
    line-height: 1.4;
  }

   .paper-tag{
    font-weight: 600;
    font-size: 0.85rem;
    padding: 1px 8px;
    border-radius: 999px;
    border: 1px solid;
    letter-spacing: 0.02em;
    box-shadow: 0 1px 2px rgba(17,24,39,0.06);
  }
  .paper-tag[data-type="arxiv"]{
    background: rgba(107,114,128,0.14);   /* gray-500 */
    color: #4b5563;                       /* gray-600 */
    border-color: rgba(107,114,128,0.28);
  }
  .paper-tag[data-type="conf"]{
    background: rgba(99,102,241,0.16);    /* indigo-500 */
    color: #4338ca;                       /* indigo-700 */
    border-color: rgba(99,102,241,0.32);
  }
  .paper-tag[data-type="journal"]{
    background: rgba(139,92,246,0.18);    /* violet-500 */
    color: #6d28d9;                       /* violet-700 */
    border-color: rgba(139,92,246,0.34);
  }
  
  .paper-authors {
    margin-top: 0.35em;
    font-size: 0.92em;
    color: var(--gray-700);
  }
  
  .paper-authors .me {
    color: var(--purple-main);
    text-decoration: underline;
    font-weight: 600;
  }
  .paper-authors span[onclick] {
    color: var(--purple-main);
  }
  .paper-authors span[onclick]:hover {
    opacity: 0.8;
  }

  .paper-meta {
    margin-top: 0.3em;
  }
  
  .paper-meta .venue {
    font-weight: 600;
    color: var(--gray-500);
    letter-spacing: 0.01em;
  }
  
/* Conference */
.paper-item[data-type="conf"] .paper-meta .venue {
    color: #4f5bd5; /* muted indigo */
  }
  
  /* Journal */
  .paper-item[data-type="journal"] .paper-meta .venue {
    color: #7a5fc7; /* soft lavender-violet */
  }
  .arxiv {
    color: #8b8fa3;
    font-weight: 500;
  }
  
  .paper-links {
    margin-top: 0.6em;
    display: flex;
    gap: 0.45em;
    flex-wrap: wrap;
    align-items: center;
  }
  
  .paper-btn {
    border: 1px solid var(--btn-border);
    background: #f9fafb;
    color: var(--text-main);
    padding: 2px 8px;
    border-radius: 12px;
    font-size: 0.85rem;
    font-weight: 500;
    transition: all 0.15s ease;
  }
  
  .paper-btn:hover {
    background: linear-gradient(
      135deg,
      var(--blue-soft),
      var(--purple-soft)
    );
    color: var(--purple-main);
    border-color: var(--purple-main);
    transform: translateY(-1px);
    box-shadow: 0 6px 14px rgba(99, 102, 241, 0.12);
}
  .paper-btn:focus{
    outline: none;
    box-shadow: none;
  }


  .paper-btn:active {
    transform: translateY(0px);
    box-shadow: 0 3px 8px rgba(99, 102, 241, 0.10);
  }
  
  .paper-btn:focus-visible {
    outline: none;
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.22);
  }

  .paper-btn-ghost{
    border-color: var(--purple-main);
    color: var(--purple-main);
  }

  .bib-popup {
    display: none;
    margin-top: 12px;
    padding: 12px;
    /* border-radius: 10px; */
    /* background: #f2fbf7; */
    /* border: 1px solid #cfeee0; */
    background: linear-gradient(
      180deg,
      rgba(247,248,255,0.96),
      rgba(242,244,252,0.96)
    );
    border: 1px solid rgba(47,58,140,0.12);
    box-shadow: 0 8px 20px rgba(47,58,140,0.08);
    border-radius: 14px;
  }
  
  .bib-popup.open {
    display: block;
  }
  
  .bib-popup pre {
    margin: 0;
    font-size: 0.8rem;
    /* background: var(--gray-100); */
    /* border: 1px solid var(--gray-200); */
    color: var(--gray-700);
  }
  .bib-popup .bib-key{
    color: #2f3a8c; 
    font-weight: 600;
  }

  .bib-popup code {
    font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
    font-size: 0.9em;
    color: var(--bib-code-fg);
    background: transparent;
    border: 0;
    padding: 0;
  }
  
  /* Dark mode */
  .dark-mode .paper-item {
    background: linear-gradient(
      180deg,
      #0b0e1a,
      #0f1224
    );
    border-color: #23264a;
    color: #e5e7eb;
  }
  .dark-mode .paper-title {
    /* color: #f1f5f9; */
    color: rgba(255,255,255,0.96);
  }
  .dark-mode .paper-tag {
    background: linear-gradient(
      135deg,
      rgba(99,102,241,0.25),
      rgba(168,139,250,0.22)
    );
    color: #e9e7ff;
    border: 1px solid rgba(168,139,250,0.35);
    box-shadow:
      inset 0 1px 0 rgba(255,255,255,0.08),
      0 4px 10px rgba(99,102,241,0.18);
    backdrop-filter: blur(6px);
  }
  
  .dark-mode .paper-authors {
    color: #c7cbe3;  
  }
  .dark-mode .me {
    color: #b7bdf8;
  }
  .dark-mode .arxiv {
    color: #9aa0c3;
  }
  
  .dark-mode .paper-meta .venue {
    color: var(--gray-400);
  }
  
/* Conference */
.dark-mode .paper-item[data-type="conf"] .paper-meta .venue {
    color: #9aa7ff; /* soft indigo tint */
  }
  
  /* Journal */
  .dark-mode .paper-item[data-type="journal"] .paper-meta .venue {
    color: #c3b5fd; /* lavender, 거의 pastel */
  }
  

  .dark-mode .paper-btn {
    background: rgba(255, 255, 255, 0.06);
    color: rgba(255, 255, 255, 0.88);
    border: 1px solid rgba(196, 181, 253, 0.28); /* soft purple border */
    box-shadow: none;
  }
  .dark-mode .paper-btn:hover {
    background: linear-gradient(
      135deg,
      var(--blue-soft),
      var(--purple-soft)
    );
    color: var(--purple-main);
    border-color: rgba(196, 181, 253, 0.45);
    transform: translateY(-1px);
  }
/* 
  .dark-mode .paper-btn.active{
    background: rgba(25, 49, 206, 0.18);
    border-color: rgba(154,167,255,0.45);
    color: #2e3ac2;
    transform: translateY(0px);
  } */
  
  
  .dark-mode .paper-btn:active {
    transform: translateY(0px);
    background: rgba(196, 181, 253, 0.10);
  }

  
  .dark-mode .paper-btn:focus-visible {
    outline: none;
    box-shadow: 0 0 0 3px rgba(196, 181, 253, 0.22);
  }
  
   .dark-mode .bib-popup {
    background: linear-gradient(
    180deg,
    rgba(15,18,30,0.92),
    rgba(10,12,22,0.92)
  );
  border: 1px solid rgba(255,255,255,0.06);
}

  .dark-mode .paper-item {
    /* border-bottom: 1px solid var(--gray-300); */
    background: transparent;
  }