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

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background-color: #f9fafb;
  color: #222;
  overflow-x: hidden;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Loading Screen */
#loading-screen {
  position: fixed;
  inset: 0;
  background-color: #ffffff;
  z-index: 10000;
  display: flex;
  justify-content: center;
  align-items: center;
  flex-direction: column;
  opacity: 0;
  user-select: none;
}

.loading-inner {
  display: flex;
  align-items: center;
  gap: 12px;
}

#loading-logo {
  width: 80px;
  height: auto;
  user-select: none;
  filter: drop-shadow(0 0 3px rgba(0, 0, 0, 0.1));
}

/* Container */
.container {
  display: flex;
  min-height: 100vh;
  max-width: 1200px;
  margin: 20px auto;
  gap: 24px;
  padding: 0 16px;
}

/* Columns */
.left-column,
.right-column {
  width: 20%;
  padding: 20px;
  background-color: #e3e8ef;
  border-radius: 12px;
  box-shadow: inset 0 0 8px #d1d9e6;
  overflow-wrap: break-word;
  word-break: break-word;
  color: #1f2937;
  font-size: 0.95rem;
}

.main-content {
  flex: 1;
  padding: 30px;
  background-color: #ffffff;
  border-radius: 16px;
  box-shadow: 0 6px 16px rgb(0 0 0 / 0.08);
  overflow-wrap: break-word;
  word-break: break-word;
  color: #111827;
  font-size: 1rem;
  line-height: 1.7;
}

/* Text inside columns */
.left-column *,
.right-column *,
.main-content * {
  overflow-wrap: break-word;
  word-break: break-word;
}

/* Profile */
.profile {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  background: #fefefe;
  padding: 20px;
  border-radius: 12px;
  box-shadow: 0 3px 8px rgba(0, 0, 0, 0.1);
  text-align: center;
  color: #374151;
  user-select: none;
}

.profile-photo {
  width: 150px;
  height: 150px;
  object-fit: cover;
  border-radius: 50%;
  border: 4px solid #cbd5e1;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
  flex-shrink: 0;
}

.profile-text h2 {
  margin-bottom: 0.3em;
  font-weight: 700;
  font-size: 1.4rem;
  color: #1e293b;
}

.profile-text h4 {
  margin-bottom: 0.8em;
  color: #6b7280;
  font-weight: 500;
}

.profile-text p {
  font-size: 1rem;
  line-height: 1.5;
  margin-bottom: 0.8em;
}

.profile-text ul {
  list-style: inside disc;
  color: #4b5563;
  font-size: 0.9rem;
  padding-left: 0;
}

.profile-text li {
  margin-bottom: 6px;
  text-align: left;
}

/* Links in right column */
.right-column ul {
  list-style: none;
  padding-left: 0;
}

.right-column ul li {
  margin-bottom: 12px;
}

.right-column ul li a {
  color: #2563eb;
  text-decoration: none;
  font-weight: 600;
  word-wrap: break-word;
}

.right-column ul li a:hover,
.right-column ul li a:focus {
  text-decoration: underline;
  outline-offset: 2px;
}

/* Hamburger Menu Button */
.hamburger {
  display: none;
  font-size: 32px;
  cursor: pointer;
  background-color: #2563eb;
  color: #fff;
  padding: 10px 22px;
  user-select: none;
  position: fixed;
  top: 12px;
  right: 12px;
  z-index: 11000;
  border-radius: 6px;
  border: none;
  transition: background-color 0.3s ease;
}

.hamburger:hover,
.hamburger:focus {
  background-color: #1e40af;
  outline-offset: 3px;
  outline: 2px solid #93c5fd;
}

/* Side Menu */
.side-menu {
  display: none;
  position: fixed;
  inset: 0;
  background-color: rgba(15, 23, 42, 0.95);
  color: #f9fafb;
  padding: 40px 20px 30px;
  z-index: 10500;
  overflow-y: auto;
  flex-direction: column;
  position: relative;
  font-size: 1.1rem;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

.side-menu.active {
  display: flex;
}

.side-menu .left-column,
.side-menu .right-column {
  width: 100%;
  background: none;
  padding-bottom: 30px;
  color: #f9fafb;
}

.side-menu .profile {
  background: none;
  border: none;
  box-shadow: none;
  text-align: center;
  color: #e0e7ff;
  font-weight: 600;
  user-select: none;
}

/* Close Button */
.close-btn {
  position: absolute;
  top: 8px;
  left: 8px;
  font-size: 48px;
  background: none;
  border: none;
  color: #fefefe;
  cursor: pointer;
  z-index: 10600;
  padding: 0;
  line-height: 1;
  transition: color 0.3s ease;
}

.close-btn:hover,
.close-btn:focus {
  color: #60a5fa;
  outline-offset: 3px;
  outline: 2px solid #93c5fd;
}

/* Desktop only display */
.desktop-only {
  display: block;
}

/* Responsive */
@media (max-width: 768px) {
  .container {
    flex-direction: column;
  }

  .left-column.desktop-only,
  .right-column.desktop-only {
    display: none;
  }

  .hamburger {
    display: block;
  }

  .main-content {
    width: 100%;
    padding: 24px 16px;
  }
}

/* Page TOC */
.page-toc {
  background: #eef2ff;
  border: 1px solid #c7d2fe;
  border-radius: 12px;
  padding: 18px 24px;
  margin-bottom: 40px;
  box-shadow: 0 3px 8px rgba(99, 102, 241, 0.1);
}

.page-toc h2 {
  font-size: 1.25rem;
  margin-bottom: 14px;
  color: #3730a3;
  border-bottom: 3px solid #4f46e5;
  padding-bottom: 6px;
  font-weight: 700;
}

.page-toc ul {
  list-style: none;
  padding-left: 0;
}

.page-toc li {
  margin: 10px 0;
}

.page-toc a {
  color: #4338ca;
  text-decoration: none;
  font-weight: 600;
  transition: color 0.3s ease;
}

.page-toc a:hover,
.page-toc a:focus {
  color: #312e81;
  text-decoration: underline;
  outline-offset: 3px;
  outline: 2px solid #a5b4fc;
}

/* Tools Heading */
.tools-heading {
  margin: 40px 0 20px;
  font-size: 1.6rem;
  color: #1e293b;
  text-align: center;
  font-weight: 700;
  position: relative;
}

.tools-heading::after {
  content: "";
  display: block;
  width: 70px;
  height: 4px;
  background: #4f46e5;
  margin: 10px auto 0;
  border-radius: 4px;
}

/* Tool Cards Grid */
.tool-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 28px;
}

/* Tool Card */
.tool-card {
  background: #ffffff;
  border: 1px solid #e0e7ff;
  border-radius: 16px;
  padding: 24px 20px 30px;
  box-shadow: 0 8px 24px rgb(99 102 241 / 0.15);
  display: flex;
  flex-direction: column;
  text-align: center;
  position: relative;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.tool-card::before {
  content: "";
  display: block;
  width: 50px;
  height: 5px;
  background: #4f46e5;
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  border-radius: 0 0 8px 8px;
}

.tool-card:hover,
.tool-card:focus-within {
  transform: translateY(-6px);
  box-shadow: 0 14px 30px rgb(99 102 241 / 0.3);
  outline: none;
}

.tool-card h3 {
  margin-bottom: 12px;
  font-size: 1.15rem;
  color: #4338ca;
  font-weight: 700;
}

.tool-card p {
  flex-grow: 1;
  font-size: 0.95rem;
  color: #4b5563;
  margin-bottom: 20px;
  line-height: 1.5;
}

.tool-card .tool-link {
  background-color: #4338ca;
  color: #fff;
  padding: 12px 18px;
  border-radius: 8px;
  font-weight: 700;
  text-decoration: none;
  display: inline-block;
  transition: background-color 0.3s ease;
}

.tool-card .tool-link:hover,
.tool-card .tool-link:focus {
  background-color: #3730a3;
  outline-offset: 3px;
  outline: 2px solid #a5b4fc;
}

/* Info Cards */
.info-card {
  background: #eef2ff;
  border-radius: 14px;
  padding: 18px 22px;
  box-shadow: 0 3px 12px rgb(147 197 253 / 0.3);
  margin-bottom: 24px;
  color: #1e293b;
  font-size: 1rem;
  line-height: 1.5;
}

.info-card h2 {
  margin-bottom: 12px;
  font-weight: 700;
  color: #1e40af;
}

.info-card a.tool-link {
  font-weight: 600;
  font-size: 1rem;
}

/* Responsive tweaks for smaller devices */
@media (max-width: 600px) {
  .page-toc {
    padding: 14px 14px;
  }

  .tool-card {
    padding: 20px 16px 26px;
  }
}
@keyframes highlight {
  0% {
    background-color: yellow;
  }
  100% {
    background-color: transparent;
  }
}

.highlighted {
  animation: highlight 2s ease forwards;
}

section {
  padding: 50px;
  margin: 20px 0;
  border: 1px solid #ccc;
}

/*====================================================================
.s_01 .accordion_one
====================================================================*/
.s_01 .accordion_one {
  max-width: 1024px;
  margin: 0 auto;
}
.s_01 .accordion_one .accordion_header {
  background-color: #EEF2FF;
  color: #1e293b;
  font-size: large;
  font-weight: bold;
  padding: 5px 11%;
  text-align: center;
  position: relative;
  z-index: +1;
  cursor: pointer;
  transition-duration: 0.2s;
}
.s_01 .accordion_one:nth-of-type(2) .accordion_header {
    background-color: #ff9a05;
}
.s_01 .accordion_one:nth-of-type(3) .accordion_header {
    background-color: #1c85d8;
}
.s_01 .accordion_one .accordion_header:hover {
  opacity: .8;
}
.s_01 .accordion_one .accordion_header .i_box {
  display: flex;
  justify-content: center;
  align-items: center;
  position: absolute;
  top: 50%;
  left: 5%;      
  right: auto;   
  width: 25px;
  height: 25px;
  border: 1px solid blue;
  margin-top: -20px;
  box-sizing: border-box;
  -webkit-transform: rotate(45deg);
  transform: rotate(45deg);
  transform-origin: center center;
  transition-duration: 0.2s;
}
.s_01 .accordion_one .accordion_header .i_box .one_i {
  display: block;
  width: 18px;
  height: 18px;
  -webkit-transform: rotate(45deg);
  transform: rotate(45deg);
  transform-origin: center center;
  transition-duration: 0.2s;
  position: relative;
}
.s_01 .accordion_one .accordion_header.open .i_box {
  -webkit-transform: rotate(-360deg);
  transform: rotate(-360deg);
}
.s_01 .accordion_one .accordion_header .i_box .one_i:before, .s_01 .accordion_one .accordion_header .i_box .one_i:after {
  display: flex;
  content: '';
  background-color: blue;
  border-radius: 10px;
  width: 18px;
  height: 4px;
  position: absolute;
  top: 7px;
  left: 0;
  -webkit-transform: rotate(0deg);
  transform: rotate(0deg);
  transform-origin: center center;
}
.s_01 .accordion_one .accordion_header .i_box .one_i:before {
  width: 4px;
  height:18px;
  top: 0;
  left: 7px;
}
.s_01 .accordion_one .accordion_header.open .i_box .one_i:before {
  content: none;
}
.s_01 .accordion_one .accordion_header.open .i_box .one_i:after {
  -webkit-transform: rotate(-45deg);
  transform: rotate(-45deg);
}
.s_01 .accordion_one .accordion_inner {
  display: none;
  padding: 30px 30px 15px 30px; 
  box-sizing: border-box;
}
.s_01 .accordion_one .accordion_inner .box_one {
  height: auto
}
.s_01 .accordion_one .accordion_inner p.txt_a_ac {
  margin: 0;
}
@media screen and (max-width: 1024px) {
  .s_01 .accordion_one .accordion_header {
    font-size: 14px;
  }
  .s_01 .accordion_one .accordion_header .i_box {
    width: 25px;
    height: 20px;
    margin-top: -15px;
  }
}
@media screen and (max-width: 767px) {
  .s_01 .accordion_one .accordion_header {
    font-size: 16px;
    text-align: left;
    padding: 15px 60px 15px 15px;
  }
}

.highlight {
  animation: shine 1.5s ease-out;
}

@keyframes shine {
  0% {
    background-color: yellow;
  }
  100% {
    background-color: transparent;
  }
}