:root{
    --bg:#f8fafc;
    --card:#ffffff;
    --text:#1e293b;
    --muted:#64748b;
    --accent:#0f766e;
    --border:#e2e8f0;
    --code:#f1f5f9;
}

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

html{
    scroll-behavior:smooth;
}

body{
    font-family:'Inter',sans-serif;
    background:var(--bg);
    color:var(--text);
    line-height:1.7;
    font-size:15px;
    overflow-x:hidden;
}

/* Container */

.container{
    max-width:1100px;
    margin:auto;
    padding:30px 20px 50px;
}

/* Home Button */

.home-btn{
    display:inline-flex;
    align-items:center;
    gap:6px;
    text-decoration:none;
    color:var(--accent);
    font-weight:600;
    margin-bottom:20px;
    font-size:14px;
}

.home-btn:hover{
    text-decoration:underline;
}

/* Header */

.article-header{
    background:var(--card);
    border:1px solid var(--border);
    border-radius:16px;
    padding:30px;
    margin-bottom:24px;
}

.article-breadcrumb{
    color:var(--muted);
    font-size:13px;
    margin-bottom:12px;
}

.article-header h1{
    font-size:2rem;
    line-height:1.2;
    margin-bottom:12px;
}

.article-meta{
    color:var(--muted);
    font-size:13px;
    margin-bottom:15px;
}

.article-summary{
    color:#334155;
    max-width:850px;
}

/* Reading Progress */

.reading-progress{
    position:fixed;
    right:16px;
    bottom:16px;
    z-index:999;
    background:var(--accent);
    color:white;
    font-size:12px;
    font-weight:700;
    padding:8px 12px;
    border-radius:999px;
    box-shadow:0 4px 14px rgba(15,23,42,.18);
}

/* Layout */

.layout{
    display:grid;
    grid-template-columns:250px 1fr;
    gap:24px;
    align-items:start;
}

/* TOC */

.toc{
    position:sticky;
    top:20px;
    background:var(--card);
    border:1px solid var(--border);
    border-radius:12px;
    padding:20px;
    height:fit-content;
    max-height:80vh;
    overflow-y:auto;
}

.toc h3{
    margin-bottom:14px;
    color:var(--accent);
    font-size:15px;
}

.toc a{
    display:block;
    text-decoration:none;
    color:var(--muted);
    font-size:13px;
    padding:6px 0;
    transition:.2s;
}

.toc a:hover{
    color:var(--accent);
}

/* Content */

.content{
    background:var(--card);
    border:1px solid var(--border);
    border-radius:16px;
    padding:35px;
    min-width:0;
}

.content h2{
    margin-top:35px;
    margin-bottom:14px;
    color:var(--accent);
    font-size:1.55rem;
    line-height:1.3;
}

.content h3{
    margin-top:25px;
    margin-bottom:10px;
    font-size:1.1rem;
}

.content p{
    margin-bottom:14px;
}

.content ul,
.content ol{
    margin-left:20px;
    margin-bottom:16px;
}

.content li{
    margin-bottom:6px;
}

/* Tables */

table{
    width:100%;
    border-collapse:collapse;
    margin:20px 0;
}

th{
    background:#f0fdfa;
    font-weight:600;
}

th,
td{
    border:1px solid var(--border);
    padding:10px;
    text-align:left;
    font-size:14px;
}

.table-wrapper{
    overflow-x:auto;
    margin:20px 0;
}

/* Notes */

.note{
    background:#f0fdfa;
    border-left:4px solid var(--accent);
    padding:15px;
    margin:20px 0;
    border-radius:8px;
}

.warning{
    background:#fff7ed;
    border-left:4px solid #f97316;
    padding:15px;
    margin:20px 0;
    border-radius:8px;
}

/* Formula */

.formula{
    background:var(--code);
    padding:12px;
    border-radius:8px;
    font-family:monospace;
    overflow-x:auto;
    margin:14px 0;
}

/* Article Images */

.content img{
    max-width:100%;
    height:auto;
    border-radius:12px;
    margin:20px 0;
    display:block;
    border:1px solid var(--border);
    background:white;
}

.article-image{
    margin:24px 0;
    text-align:center;
}

.article-image a{
    display:block;
    text-decoration:none;
}

.article-image img{
    display:block;
    width:100%;
    max-width:100%;
    height:auto;
    border-radius:12px;
    border:1px solid var(--border);
    background:white;
    cursor:zoom-in;
    transition:.2s ease;
    margin:0 auto;
}

.article-image img:hover{
    transform:scale(1.01);
}

.article-image figcaption{
    margin-top:8px;
    font-size:13px;
    color:var(--muted);
    font-style:italic;
    line-height:1.5;
}

.article-image.small img{
    max-width:520px;
}

.article-image.medium img{
    max-width:720px;
}

.article-image.large img{
    max-width:100%;
}

/* Code */

pre{
    overflow-x:auto;
    background:var(--code);
    padding:14px;
    border-radius:8px;
}

code{
    font-family:monospace;
}

/* Back Home */

.back-home{
    display:inline-flex;
    align-items:center;
    gap:6px;
    text-decoration:none;
    color:var(--accent);
    font-weight:600;
    margin-top:30px;
}

.back-home:hover{
    text-decoration:underline;
}

/* Footer */

.footer{
    margin-top:40px;
    padding-top:20px;
    border-top:1px solid var(--border);
    text-align:center;
    color:var(--muted);
    font-size:13px;
}

/* Tablet */

@media (max-width:900px){

    .layout{
        display:block;
    }

    .toc{
        position:relative;
        top:auto;
        margin-bottom:20px;
        max-height:220px;
        overflow-y:auto;
    }

    .content{
        padding:24px;
    }

    .article-header{
        padding:24px;
    }

    .article-header h1{
        font-size:1.75rem;
    }
}

/* Mobile */

@media (max-width:600px){

    .container{
        padding:15px 12px 40px;
    }

    .article-header{
        padding:18px;
        border-radius:12px;
    }

    .article-header h1{
        font-size:1.5rem;
        line-height:1.25;
        word-break:break-word;
    }

    .article-summary{
        font-size:14px;
    }

    .content{
        padding:18px;
        border-radius:12px;
    }

    .content h2{
        font-size:1.3rem;
        margin-top:28px;
    }

    .content h3{
        font-size:1.05rem;
    }

    .toc{
        padding:15px;
    }

    .toc h3{
        font-size:14px;
    }

    .toc a{
        font-size:14px;
        padding:8px 0;
    }

    table{
        display:block;
        overflow-x:auto;
        white-space:nowrap;
    }

    th,
    td{
        font-size:13px;
        padding:8px;
    }

    .note,
    .warning{
        padding:12px;
    }

    .formula{
        font-size:13px;
    }

    .reading-progress{
        right:12px;
        bottom:12px;
        font-size:11px;
        padding:7px 10px;
    }

    .article-image{
        margin:20px 0;
    }

    .article-image.small img,
    .article-image.medium img{
        max-width:100%;
    }
}


/* ==========================================================================
   Learn Medicine — Floating Article Narration
   Combined into article.css so article pages need no additional stylesheet.
   ========================================================================== */

/*
 * Learn Medicine — Floating Article Narration v4.1.0
 * Compact floating launcher + floating player for desktop and mobile.
 */

.narration-floating-root {
  --narration-progress: 0deg;
  --narration-accent: var(--accent, #0f766e);
  --narration-card: var(--card, #ffffff);
  --narration-bg: var(--bg, #f8fafc);
  --narration-text: var(--text, #1e293b);
  --narration-muted: var(--muted, #64748b);
  --narration-border: var(--border, #e2e8f0);
  --narration-soft: var(--soft, #f0fdfa);
  --narration-right: max(14px, env(safe-area-inset-right));
  --narration-launcher-bottom: max(78px, calc(env(safe-area-inset-bottom) + 78px));
  --narration-panel-bottom: max(144px, calc(env(safe-area-inset-bottom) + 144px));
  position: fixed !important;
  inset: 0 !important;
  z-index: 2147483000 !important;
  pointer-events: none !important;
  font-family: Inter, Arial, sans-serif !important;
}

.narration-floating-root *,
.narration-floating-root *::before,
.narration-floating-root *::after {
  box-sizing: border-box;
}

.narration-launcher {
  position: fixed !important;
  right: var(--narration-right) !important;
  bottom: var(--narration-launcher-bottom) !important;
  z-index: 2147483002 !important;
  width: 54px !important;
  height: 54px !important;
  margin: 0 !important;
  padding: 0 !important;
  overflow: visible !important;
  border: 0 !important;
  border-radius: 50% !important;
  background: transparent !important;
  box-shadow: none !important;
  color: var(--narration-accent) !important;
  pointer-events: auto !important;
  cursor: pointer !important;
  touch-action: manipulation !important;
  -webkit-appearance: none !important;
  appearance: none !important;
  -webkit-tap-highlight-color: transparent !important;
  filter: drop-shadow(0 7px 16px rgba(15, 23, 42, 0.22));
  transition: transform 150ms ease, filter 150ms ease;
}

.narration-launcher:hover {
  transform: translateY(-2px);
  filter: drop-shadow(0 10px 22px rgba(15, 23, 42, 0.28));
}

.narration-launcher:active {
  transform: scale(0.96);
}

.narration-launcher:focus-visible,
.narration-close:focus-visible,
.narration-play:focus-visible,
.narration-icon-button:focus-visible,
.narration-text-button:focus-visible,
.narration-rate-button:focus-visible,
.narration-voice:focus-visible {
  outline: 3px solid rgba(15, 118, 110, 0.28) !important;
  outline-offset: 3px !important;
}

.narration-launcher-ring {
  position: absolute;
  inset: 0;
  display: block;
  border-radius: 50%;
  background: conic-gradient(
    var(--narration-accent) var(--narration-progress),
    var(--narration-border) 0
  );
}

.narration-launcher-ring::after {
  content: "";
  position: absolute;
  inset: 3px;
  border: 1px solid rgba(255, 255, 255, 0.78);
  border-radius: 50%;
  background: var(--narration-card);
}

.narration-launcher-core {
  position: absolute;
  inset: 6px;
  z-index: 2;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--narration-card);
  transition: background 150ms ease, color 150ms ease;
}

.narration-launcher-svg {
  width: 25px;
  height: 25px;
  overflow: visible;
  fill: currentColor;
}

.narration-launcher-svg .narration-wave {
  fill: none;
  stroke: currentColor;
  stroke-width: 1.9;
  stroke-linecap: round;
}

.narration-launcher-badge {
  position: absolute;
  top: 2px;
  right: 2px;
  z-index: 4;
  width: 13px;
  height: 13px;
  border: 2px solid var(--narration-card);
  border-radius: 50%;
  background: transparent;
}

.narration-launcher.is-playing .narration-launcher-core {
  background: var(--narration-accent);
  color: #ffffff !important;
}

.narration-launcher.is-playing .narration-launcher-badge {
  background: #22c55e;
  animation: narration-pulse 1.4s ease-in-out infinite;
}

.narration-launcher.is-playing .wave-one,
.narration-launcher.is-playing .wave-two {
  animation: narration-wave 1.1s ease-in-out infinite;
  transform-origin: center;
}

.narration-launcher.is-playing .wave-two {
  animation-delay: 120ms;
}

.narration-player {
  position: fixed !important;
  right: var(--narration-right) !important;
  bottom: var(--narration-panel-bottom) !important;
  z-index: 2147483001 !important;
  width: min(400px, calc(100vw - 28px)) !important;
  max-height: min(72dvh, 620px) !important;
  margin: 0 !important;
  padding: 15px !important;
  overflow-x: hidden !important;
  overflow-y: auto !important;
  overscroll-behavior: contain;
  border: 1px solid var(--narration-border) !important;
  border-top: 4px solid var(--narration-accent) !important;
  border-radius: 17px !important;
  background: color-mix(in srgb, var(--narration-card) 97%, transparent) !important;
  color: var(--narration-text) !important;
  box-shadow: 0 22px 55px rgba(15, 23, 42, 0.26) !important;
  pointer-events: auto !important;
  -webkit-backdrop-filter: blur(16px);
  backdrop-filter: blur(16px);
  transform-origin: bottom right;
}

.narration-player[hidden] {
  display: none !important;
}

.narration-player.is-open {
  animation: narration-panel-in 170ms ease-out;
}

.narration-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
}

.narration-header-copy {
  min-width: 0;
}

.narration-eyebrow {
  color: var(--narration-accent);
  font-size: 0.7rem;
  font-weight: 800;
  letter-spacing: 0.08em;
}

.narration-status {
  margin-top: 2px;
  color: var(--narration-muted);
  font-size: 0.82rem;
  font-weight: 600;
}

.narration-close {
  flex: 0 0 auto;
  display: grid !important;
  place-items: center;
  width: 32px !important;
  height: 32px !important;
  margin: 0 !important;
  padding: 0 !important;
  border: 1px solid var(--narration-border) !important;
  border-radius: 10px !important;
  background: var(--narration-bg) !important;
  color: var(--narration-text) !important;
  font: inherit !important;
  font-size: 1.25rem !important;
  line-height: 1 !important;
  cursor: pointer !important;
  -webkit-appearance: none !important;
  appearance: none !important;
}

.narration-close:hover {
  border-color: var(--narration-accent) !important;
  background: var(--narration-soft) !important;
}

.narration-now-reading {
  display: grid;
  gap: 3px;
  margin-top: 12px;
  padding: 11px 12px;
  border: 1px solid color-mix(in srgb, var(--narration-accent) 14%, var(--narration-border));
  border-radius: 12px;
  background: var(--narration-soft);
}

.narration-now-label {
  color: var(--narration-muted);
  font-size: 0.68rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.narration-section-title {
  overflow: hidden;
  color: var(--narration-text);
  font-size: 0.89rem;
  line-height: 1.3;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.narration-current-text {
  display: -webkit-box;
  overflow: hidden;
  color: var(--narration-muted);
  font-size: 0.77rem;
  line-height: 1.45;
  -webkit-box-orient: vertical;
  -webkit-line-clamp: 2;
}

.narration-progress-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: 9px;
  margin-top: 12px;
}

.narration-progress-track {
  height: 6px;
  overflow: hidden;
  border-radius: 999px;
  background: var(--narration-border);
}

.narration-progress-fill {
  width: 0;
  height: 100%;
  border-radius: inherit;
  background: var(--narration-accent);
  transition: width 180ms ease;
}

.narration-progress-text {
  min-width: 34px;
  color: var(--narration-muted);
  font-size: 0.73rem;
  font-variant-numeric: tabular-nums;
  text-align: right;
}

.narration-main-controls {
  display: grid;
  grid-template-columns: 46px minmax(0, 1fr) 46px;
  align-items: center;
  gap: 9px;
  margin-top: 13px;
}

.narration-icon-button,
.narration-play,
.narration-text-button,
.narration-rate-button {
  margin: 0 !important;
  font-family: inherit !important;
  cursor: pointer !important;
  -webkit-appearance: none !important;
  appearance: none !important;
  touch-action: manipulation;
}

.narration-icon-button {
  display: grid !important;
  place-items: center;
  width: 46px !important;
  height: 46px !important;
  padding: 0 !important;
  border: 1px solid var(--narration-border) !important;
  border-radius: 13px !important;
  background: var(--narration-card) !important;
  color: var(--narration-text) !important;
  font-size: 1.15rem !important;
}

.narration-play {
  display: inline-flex !important;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 46px !important;
  padding: 9px 16px !important;
  border: 1px solid var(--narration-accent) !important;
  border-radius: 13px !important;
  background: var(--narration-accent) !important;
  color: #ffffff !important;
  font-size: 0.9rem !important;
  font-weight: 750 !important;
}

.narration-play:hover,
.narration-icon-button:hover,
.narration-text-button:hover,
.narration-rate-button:hover {
  filter: brightness(0.97);
}

.narration-secondary-controls {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 8px;
  margin-top: 9px;
}

.narration-text-button {
  min-height: 38px !important;
  padding: 7px 10px !important;
  border: 1px solid var(--narration-border) !important;
  border-radius: 10px !important;
  background: var(--narration-card) !important;
  color: var(--narration-text) !important;
  font-size: 0.77rem !important;
  font-weight: 650 !important;
}

.narration-reset {
  color: var(--narration-accent) !important;
}

.narration-settings {
  display: grid;
  gap: 12px;
  margin-top: 13px;
  padding-top: 12px;
  border-top: 1px solid var(--narration-border);
}

.narration-setting-group,
.narration-voice-field {
  display: grid;
  gap: 6px;
}

.narration-setting-label {
  color: var(--narration-muted);
  font-size: 0.7rem;
  font-weight: 750;
}

.narration-rate-buttons {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: 5px;
}

.narration-rate-button {
  min-width: 0 !important;
  min-height: 34px !important;
  padding: 5px 3px !important;
  border: 1px solid var(--narration-border) !important;
  border-radius: 9px !important;
  background: var(--narration-card) !important;
  color: var(--narration-muted) !important;
  font-size: 0.68rem !important;
  font-weight: 700 !important;
}

.narration-rate-button.is-selected {
  border-color: var(--narration-accent) !important;
  background: var(--narration-soft) !important;
  color: var(--narration-accent) !important;
}

.narration-voice {
  width: 100% !important;
  min-height: 40px !important;
  margin: 0 !important;
  padding: 7px 34px 7px 10px !important;
  border: 1px solid var(--narration-border) !important;
  border-radius: 10px !important;
  background: var(--narration-card) !important;
  color: var(--narration-text) !important;
  font: inherit !important;
  font-size: 0.77rem !important;
}

.narration-icon-button:disabled,
.narration-play:disabled,
.narration-text-button:disabled,
.narration-rate-button:disabled,
.narration-voice:disabled {
  cursor: not-allowed !important;
  opacity: 0.42 !important;
}

.narration-active {
  scroll-margin-top: 110px;
  border-radius: 6px;
  background: rgba(15, 118, 110, 0.1) !important;
  box-shadow: 0 0 0 4px rgba(15, 118, 110, 0.09) !important;
  transition: background 180ms ease, box-shadow 180ms ease;
}

.narration-unavailable .narration-launcher-ring {
  filter: grayscale(1);
}

.narration-unavailable .narration-launcher-core {
  color: var(--narration-muted) !important;
}

@media (max-width: 640px) {
  .narration-floating-root {
    --narration-right: max(10px, env(safe-area-inset-right));
    --narration-launcher-bottom: max(76px, calc(env(safe-area-inset-bottom) + 76px));
    --narration-panel-bottom: max(136px, calc(env(safe-area-inset-bottom) + 136px));
  }

  .narration-launcher {
    width: 50px !important;
    height: 50px !important;
  }

  .narration-launcher-svg {
    width: 23px;
    height: 23px;
  }

  .narration-player {
    left: max(10px, env(safe-area-inset-left)) !important;
    right: max(10px, env(safe-area-inset-right)) !important;
    bottom: var(--narration-panel-bottom) !important;
    width: auto !important;
    max-height: min(67dvh, calc(100dvh - 160px)) !important;
    padding: 13px !important;
    border-radius: 15px !important;
    transform-origin: bottom right;
  }

  .narration-now-reading {
    margin-top: 10px;
    padding: 9px 10px;
  }

  .narration-main-controls {
    margin-top: 11px;
  }

  .narration-secondary-controls {
    grid-template-columns: 1fr 0.72fr;
  }

  .narration-settings {
    margin-top: 11px;
    padding-top: 10px;
  }

  .narration-rate-buttons {
    grid-template-columns: repeat(3, 1fr);
  }

  .narration-rate-button {
    min-height: 32px !important;
  }
}

@media (max-width: 360px) {
  .narration-player {
    padding: 11px !important;
  }

  .narration-section-title {
    font-size: 0.83rem;
  }

  .narration-current-text {
    font-size: 0.72rem;
  }
}

@keyframes narration-panel-in {
  from {
    opacity: 0;
    transform: translateY(8px) scale(0.98);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

@keyframes narration-pulse {
  0%, 100% {
    box-shadow: 0 0 0 0 rgba(34, 197, 94, 0.32);
  }
  50% {
    box-shadow: 0 0 0 6px rgba(34, 197, 94, 0);
  }
}

@keyframes narration-wave {
  0%, 100% {
    opacity: 0.55;
  }
  50% {
    opacity: 1;
  }
}

@media (prefers-reduced-motion: reduce) {
  .narration-player,
  .narration-launcher,
  .narration-launcher-badge,
  .narration-launcher-svg .narration-wave,
  .narration-progress-fill,
  .narration-active {
    animation: none !important;
    transition: none !important;
  }
}


/* ==========================================================================\n   Combined progress + narration integration\n   ========================================================================== */

.reading-progress {
    min-width:54px;
    min-height:54px;
    display:grid;
    place-items:center;
    padding:8px 10px;
    pointer-events:none;
    font-variant-numeric:tabular-nums;
}

@media (max-width:600px){
    .reading-progress{
        min-width:50px;
        min-height:50px;
        padding:7px 9px;
    }
}