/* Google Fonts Import */
@import url('https://fonts.googleapis.com/css2?family=Caveat:wght@400;700&family=Kalam:wght@400;700&family=Patrick+Hand&display=swap');

/* Color Variables & Config */
:root {
  --desk-bg: #f3f4f6;
  --desk-grid: rgba(209, 213, 219, 0.6);
  --paper-bg: #fffdf8;
  --ink-blue: #1e3a8a;
  --ink-black: #1e293b;
  --ink-red: #c2255c;
  --margin-line: rgba(239, 68, 68, 0.4);
  --note-line: rgba(59, 130, 246, 0.08);

  /* Highlighter Colors */
  --hl-yellow: linear-gradient(100deg, rgba(254, 240, 138, 0.7) 0%, rgba(253, 224, 71, 0.9) 70%, rgba(254, 240, 138, 0.4) 100%);
  --hl-pink: linear-gradient(100deg, rgba(251, 207, 232, 0.7) 0%, rgba(244, 114, 182, 0.8) 70%, rgba(251, 207, 232, 0.4) 100%);
  --hl-blue: linear-gradient(100deg, rgba(191, 219, 254, 0.7) 0%, rgba(96, 165, 250, 0.8) 70%, rgba(191, 219, 254, 0.4) 100%);
  --hl-green: linear-gradient(100deg, rgba(187, 247, 208, 0.7) 0%, rgba(74, 222, 128, 0.8) 70%, rgba(187, 247, 208, 0.4) 100%);
}

/* Desk Background with Dot Grid */
body {
  background-color: var(--desk-bg);
  background-image: radial-gradient(var(--desk-grid) 1.5px, transparent 1.5px);
  background-size: 24px 24px;
  margin: 0;
  padding: 40px 1px;
  font-family: 'Patrick Hand', cursive;
  color: var(--ink-black);
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
}

/* Notebook Container */
.notebook-container {
  width: 100%;
  max-width: 1760px;
  display: flex;
  flex-direction: column;
  gap: 50px;
}

/* Individual Paper Page */
.paper-page {
  position: relative;
  background-color: var(--paper-bg);
  /* Lined paper effect + red margin line */
  background-image:
    linear-gradient(90deg, transparent 66px, var(--margin-line) 66px, var(--margin-line) 68px, transparent 68px),
    linear-gradient(var(--note-line) 96%, transparent 96%);
  background-size: 100% 100%, 100% 32px;
  background-position: 0 0, 0 12px;

  /* Visual depth */
  border-radius: 4px 16px 16px 4px;
  box-shadow:
    0 15px 35px rgba(0, 0, 0, 0.05),
    0 5px 15px rgba(0, 0, 0, 0.03),
    0 0 0 1px rgba(0, 0, 0, 0.04),
    /* stacked page effect under the main page */
    5px 5px 0px #fffdf8,
    5px 5px 2px rgba(0, 0, 0, 0.02),
    10px 10px 0px #fffcf5,
    10px 10px 4px rgba(0, 0, 0, 0.02);

  padding: 60px 50px 60px 90px;
  /* Offset for red line and binding */
  min-height: 500px;
  box-sizing: border-box;
}

/* Spiral Binding Binder Holes */
.paper-page::before {
  content: '';
  position: absolute;
  top: 40px;
  bottom: 40px;
  left: 20px;
  width: 14px;
  background-image: radial-gradient(circle, #374151 55%, transparent 63%);
  background-size: 14px 32px;
  background-repeat: repeat-y;
  background-position: 0 12px;
  opacity: 0.8;
  mix-blend-mode: multiply;
  z-index: 10;
}

/* Metal Spiral Rings */
.paper-page::after {
  content: '';
  position: absolute;
  top: 36px;
  bottom: 44px;
  left: 6px;
  width: 32px;
  /* Simulates metallic rings looping through holes */
  background-image: linear-gradient(180deg,
      transparent 0px,
      transparent 4px,
      #9ca3af 4px,
      #e5e7eb 8px,
      #ffffff 10px,
      #d1d5db 12px,
      #4b5563 16px,
      transparent 16px,
      transparent 32px);
  background-size: 32px 32px;
  background-repeat: repeat-y;
  background-position: 0 12px;
  z-index: 11;
  filter: drop-shadow(2px 2px 3px rgba(0, 0, 0, 0.18));
}

/* Headings */
h1 {
  font-family: 'Kalam', cursive;
  font-weight: 700;
  font-size: 36px;
  line-height: 48px;
  color: var(--ink-blue);
  text-align: center;
  margin-top: 0;
  margin-bottom: 40px;
  letter-spacing: 0.5px;
  text-transform: uppercase;
}

h2 {
  font-family: 'Kalam', cursive;
  font-weight: 700;
  font-size: 26px;
  line-height: 32px;
  color: var(--ink-blue);
  margin-top: 32px;
  margin-bottom: 24px;
  position: relative;
  display: inline-block;
}

/* Hand-drawn underline for headings */
h2::after {
  content: '';
  display: block;
  width: 100%;
  height: 6px;
  background: rgba(59, 130, 246, 0.2);
  border-radius: 4px;
  margin-top: 2px;
  transform: rotate(-0.5deg);
}

h3 {
  font-family: 'Kalam', cursive;
  font-weight: 700;
  font-size: 22px;
  line-height: 32px;
  color: var(--ink-blue);
  margin-top: 24px;
  margin-bottom: 16px;
}

/* Paragraphs & Lists */
p {
  font-size: 20px;
  line-height: 32px;
  margin-top: 0;
  margin-bottom: 32px;
  text-align: justify;
}

ul,
ol {
  margin-top: 0;
  margin-bottom: 32px;
  padding-left: 24px;
}

li {
  font-size: 20px;
  line-height: 32px;
  margin-bottom: 12px;
}

/* Standard Highlight */
strong {
  font-weight: bold;
  background: var(--hl-yellow);
  padding: 1px 6px;
  border-radius: 4px 8px 3px 6px;
  margin: 0 -2px;
  display: inline;
  box-shadow: 1px 1px 2px rgba(0, 0, 0, 0.01);
}

/* Red annotations / cursive notes */
em {
  font-family: 'Caveat', cursive;
  font-style: normal;
  font-size: 24px;
  line-height: 28px;
  color: var(--ink-red);
  padding: 0 4px;
}

/* Custom Highlight colors */
.hl-pink {
  background: var(--hl-pink);
  border-radius: 6px 3px 8px 4px;
}

.hl-blue {
  background: var(--hl-blue);
  border-radius: 4px 6px 3px 8px;
}

.hl-green {
  background: var(--hl-green);
  border-radius: 8px 4px 6px 3px;
}

/* Sticky Note (Post-it) Block */
.sticky-note {
  background: #fef08a;
  /* post-it yellow */
  padding: 24px;
  margin: 36px 0;
  border-radius: 3px 15px 5px 20px/20px 5px 15px 3px;
  /* Uneven borders */
  box-shadow:
    3px 12px 18px rgba(0, 0, 0, 0.06),
    0px 1px 3px rgba(0, 0, 0, 0.04);
  transform: rotate(-1.5deg);
  /* natural slight tilt */
  position: relative;
  color: #1e293b;
  border-left: 5px solid #facc15;
}

.sticky-note::before {
  /* Subtle tape effect at the top */
  content: '';
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%) rotate(1deg);
  width: 90px;
  height: 24px;
  background: rgba(255, 255, 255, 0.45);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
  backdrop-filter: blur(1px);
}

/* Sticky Note Variations */
.pink-note {
  background: #fbcfe8;
  border-left-color: #ec4899;
  transform: rotate(1deg);
}

.pink-note::before {
  transform: translateX(-50%) rotate(-2deg);
}

.blue-note {
  background: #dbeafe;
  border-left-color: #3b82f6;
  transform: rotate(-0.8deg);
}

.blue-note::before {
  transform: translateX(-50%) rotate(1.5deg);
}

.sticky-note p {
  margin-bottom: 16px;
  font-size: 19px;
  line-height: 28px;
}

.sticky-note p:last-child {
  margin-bottom: 0;
}

.sticky-note ul {
  margin-bottom: 0;
}

/* Handwritten Q&A Block */
.qa-block {
  border-left: 3px solid rgba(30, 58, 138, 0.15);
  padding-left: 20px;
  margin: 28px 0;
}

.ans-text {
  font-size: 20px;
  line-height: 32px;
  color: var(--ink-black);
}

.key-points {
  background-color: rgba(30, 58, 138, 0.02);
  border: 1px dashed rgba(30, 58, 138, 0.15);
  padding: 16px 20px;
  border-radius: 8px;
  margin-top: 16px;
}

/* Hand-drawn Tables */
table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  margin: 36px 0;
  border: 2px solid #475569;
  border-radius: 12px 6px 15px 5px/6px 15px 5px 12px;
  /* Sketchy table container */
  background-color: rgba(255, 255, 255, 0.4);
  overflow: hidden;
  box-shadow: 2px 8px 15px rgba(0, 0, 0, 0.02);
}

th,
td {
  border-right: 2px solid rgba(71, 85, 105, 0.6);
  border-bottom: 2px solid rgba(71, 85, 105, 0.6);
  padding: 12px 18px;
  font-family: 'Patrick Hand', cursive;
  font-size: 19px;
  line-height: 28px;
  vertical-align: top;
}

th:last-child,
td:last-child {
  border-right: none;
}

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

th {
  background-color: rgba(254, 240, 138, 0.4);
  /* Highlighter yellow header */
  color: var(--ink-blue);
  font-family: 'Kalam', cursive;
  font-weight: 700;
  font-size: 21px;
  text-align: left;
}

/* Custom badges */
.badge {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 4px;
  font-weight: bold;
  font-family: 'Kalam', cursive;
  font-size: 14px;
  margin-right: 8px;
  text-transform: uppercase;
}

.q-badge {
  background-color: #fee2e2;
  color: #ef4444;
  border: 1px solid rgba(239, 68, 68, 0.2);
}

/* Print Optimization */
@media print {
  body {
    background: none;
    padding: 0;
  }

  .paper-page {
    box-shadow: none;
    background-image: none;
    padding: 20px;
    page-break-after: always;
  }

  .paper-page::before,
  .paper-page::after {
    display: none;
  }
}

/* --- Diagram Component Styles --- */
.diagram-container {
  margin: 24px auto;
  padding: 16px;
  /* background-color: rgba(255, 255, 255, 0.5); */
  border: 2px dashed #d1d5db;
  /* Subtle dashed line for a sketched feel */
  border-radius: 8px;
  text-align: center;
  max-width: 90%;
  /* Prevents it from stretching too wide on large screens */
}

.diagram-container-wide {
  margin: 24px auto;
  padding: 16px;
  /* background-color: rgba(255, 255, 255, 0.5); */
  border: 2px dashed #d1d5db;
  /* Subtle dashed line for a sketched feel */
  border-radius: 8px;
  text-align: center;
  max-width: 100%;
  /* Prevents it from stretching too wide on large screens */
}

.diagram-image {
  max-width: 50%;
  height: auto;
  border-radius: 4px;
  box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  /* display: block; */
  margin: 0 auto;
}

.diagram-image-wide {
  max-width: 70%;
  height: auto;
  border-radius: 4px;
  box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  /* display: block; */
  margin: 0 auto;
}

.diagram-caption {
  margin-top: 12px;
  font-family: 'Kalam', cursive;
  /* Aligns with your existing font imports */
  font-size: 16px;
  color: #4b5563;
  font-style: italic;
}

/* --- Floating Collapsible Navigation Drawer --- */
.floating-nav {
  position: fixed;
  bottom: 24px;
  right: 24px;
  z-index: 1000;
  font-family: 'Kalam', cursive;
}

#nav-checkbox {
  display: none;
}

.nav-trigger {
  width: 50px;
  height: 50px;
  background: var(--paper-bg);
  border: 2px solid #4b5563;
  border-radius: 50%;
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.15);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  z-index: 1002;
  position: relative;
  transition: transform 0.2s ease, background-color 0.2s ease;
}

.nav-trigger:hover {
  background: #fef08a;
  /* post-it yellow hover */
  transform: scale(1.05);
}

.nav-trigger svg {
  color: var(--ink-blue);
  width: 24px;
  height: 24px;
}

.nav-drawer {
  position: absolute;
  bottom: 60px;
  right: 0;
  width: 260px;
  background: var(--paper-bg);
  border: 2px solid #4b5563;
  border-radius: 12px;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
  padding: 16px;
  display: none;
  flex-direction: column;
  gap: 8px;
  z-index: 1001;
}

#nav-checkbox:checked~.nav-drawer {
  display: flex;
}

.nav-drawer-title {
  font-weight: 700;
  font-size: 18px;
  color: var(--ink-blue);
  border-bottom: 2px dashed rgba(30, 58, 138, 0.2);
  padding-bottom: 8px;
  margin-bottom: 4px;
}

.nav-drawer-link {
  text-decoration: none;
  color: var(--ink-black);
  font-size: 18px;
  padding: 4px 8px;
  border-radius: 4px;
  transition: background 0.2s ease, color 0.2s ease;
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-drawer-link:hover {
  background: rgba(30, 58, 138, 0.06);
  color: var(--ink-red);
}

.nav-drawer-link.active {
  background: rgba(254, 240, 138, 0.5);
  /* highlighted */
  font-weight: bold;
}

.nav-drawer-divider {
  border-top: 1px dashed rgba(71, 85, 105, 0.3);
  margin: 4px 0;
}

/* --- Floating Scroll-Adaptive Back Button --- */
.back-to-hub-btn {
  position: fixed;
  top: 20px;
  left: 20px;
  z-index: 999;
  background: var(--paper-bg);
  border: 2px solid #4b5563;
  padding: 6px 14px;
  border-radius: 6px;
  color: var(--ink-blue);
  text-decoration: none;
  font-family: 'Kalam', cursive;
  font-size: 16px;
  transition: top 0.3s ease;
  box-shadow: 2px 2px 5px rgba(0, 0, 0, 0.1);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.back-to-hub-btn:hover {
  background: #fef08a;
  /* post-it yellow hover */
  color: var(--ink-red);
}

.back-to-hub-btn.hide {
  top: -60px;
}

/* --- Easter Egg Steaming Teacup Styles --- */
.chai-overlay {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.4);
  backdrop-filter: blur(4px);
  z-index: 1000;
  justify-content: center;
  align-items: center;
  font-family: 'Kalam', cursive;
}

.chai-cup-card {
  background: var(--paper-bg);
  border: 2px solid #4b5563;
  border-radius: 12px;
  padding: 30px;
  width: 320px;
  text-align: center;
  box-shadow: 5px 15px 30px rgba(0, 0, 0, 0.15);
  position: relative;
  transform: rotate(-1deg);
}

.cup-container {
  position: relative;
  width: 100px;
  height: 80px;
  margin: 0 auto 20px;
}

.cup {
  position: absolute;
  bottom: 10px;
  left: 20px;
  width: 60px;
  height: 50px;
  background: #f59e0b;
  /* Amber clay cup look */
  border: 2px solid #4b5563;
  border-radius: 0 0 30px 30px;
}

.cup-handle {
  position: absolute;
  bottom: 22px;
  left: 76px;
  width: 12px;
  height: 22px;
  border: 2px solid #4b5563;
  border-left: none;
  border-radius: 0 12px 12px 0;
}

.cup-saucer {
  position: absolute;
  bottom: 4px;
  left: 10px;
  width: 80px;
  height: 8px;
  background: #d97706;
  border: 2px solid #4b5563;
  border-radius: 4px;
}

.steam-lines {
  position: absolute;
  top: 10px;
  left: 35px;
  display: flex;
  gap: 8px;
}

.steam {
  width: 4px;
  height: 25px;
  background: rgba(75, 85, 99, 0.4);
  border-radius: 2px;
  animation: floatSteam 2s infinite ease-in-out;
}

.steam:nth-child(2) {
  animation-delay: 0.4s;
  height: 32px;
}

.steam:nth-child(3) {
  animation-delay: 0.8s;
}

@keyframes floatSteam {
  0% {
    transform: translateY(0) scaleY(1);
    opacity: 0;
  }

  50% {
    transform: translateY(-8px) scaleY(1.2);
    opacity: 0.6;
  }

  100% {
    transform: translateY(-16px) scaleY(0.8);
    opacity: 0;
  }
}

.chai-btn-close {
  background: var(--ink-red);
  color: white;
  border: 2px solid #4b5563;
  font-family: inherit;
  font-size: 18px;
  padding: 6px 16px;
  border-radius: 6px;
  cursor: pointer;
  margin-top: 16px;
  box-shadow: 2px 2px 0px #4b5563;
}

.chai-btn-close:hover {
  background: #a61c4c;
  transform: translate(1px, 1px);
  box-shadow: 1px 1px 0px #4b5563;
}

.summon-chai-link {
  color: var(--ink-blue);
  text-decoration: underline dotted;
  cursor: pointer;
  font-weight: bold;
}

.summon-chai-link:hover {
  color: var(--ink-red);
}