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

body {
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  background-color: #f0f0f0;
  color: #333;
  line-height: 1.6;
}

/* container */
.container {
  max-width: 960px;
  margin: 0 auto;
  padding: 20px;
}

/* header */
header {
  text-align: center;
  padding: 60px 0;
  background-color: #2c3e50;
  color: white;
  border-radius: 8px;
  margin-bottom: 40px;
}

header h1 {
  font-size: 36px;
  font-weight: 700;
  letter-spacing: 2px;
  color: #ecf0f1;
}

header p {
  font-size: 18px;
  font-style: italic;
  color: #bdc3c7;
  margin-top: 10px;
}

/* main */
main {
  padding-bottom: 40px;
}

/* 보드판 배경 */
body {
  background: url("https://www.transparenttextures.com/patterns/wood-pattern.png"); /* 나무 질감 배경 */
  background-color: #f0f0f0;
}

/* 카드 스타일 */
.card {
  background-color: #fff;
  padding: 30px;
  margin-bottom: 20px;
  border-radius: 8px;
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
  position: relative;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card.sticker::before {
  content: "";
  background: url(./2303175_clip_document_office_paper_pin_icon.png) no-repeat
    center center;
  background-size: contain;
  position: absolute;
  top: -20px;
  left: 20px;
  width: 50px;
  height: 50px;
  z-index: 10;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
}

.card h2 {
  font-size: 24px;
  color: #2c3e50;
  margin-bottom: 10px;
}

.card p {
  font-size: 16px;
  color: #7f8c8d;
  margin-bottom: 10px;
}

.card.sticker ul {
  margin-left: 4ex;
}

a {
  color: #2980b9;
  text-decoration: none;
  font-weight: 500;
}

a:hover {
  text-decoration: underline;
  color: #3498db;
}

/* footer */
footer {
  text-align: center;
  padding: 20px;
  background-color: #2c3e50;
  color: white;
  border-radius: 8px;
}

/* 반응형 디자인 */
@media screen and (max-width: 768px) {
  header h1 {
    font-size: 30px;
  }

  header p {
    font-size: 16px;
  }

  .card h2 {
    font-size: 20px;
  }

  .card p {
    font-size: 14px;
  }

  footer p {
    font-size: 14px;
  }
}

@media screen and (max-width: 480px) {
  header h1 {
    font-size: 24px;
  }

  .card h2 {
    font-size: 18px;
  }

  .card p {
    font-size: 13px;
  }

  footer p {
    font-size: 12px;
  }
}

/* improve */
:root {
  --primary-color: #2c3e50;
  --secondary-color: #2980b9;
  --text-color: #333;
  --light-gray: #f0f0f0;
  --card-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
}

/* 검색 컨테이너 */
.search-container {
  margin-top: 20px;
  display: flex;
  gap: 10px;
  justify-content: center;
}

#searchInput {
  padding: 10px;
  width: 300px;
  border: none;
  border-radius: 4px;
  font-size: 16px;
}

#monthFilter {
  padding: 10px;
  border: none;
  border-radius: 4px;
  font-size: 16px;
  background-color: white;
}

/* 통계 카드 */
.stats-container {
  display: flex;
  gap: 20px;
  margin-bottom: 30px;
}

.stat-card {
  background-color: white;
  padding: 20px;
  border-radius: 8px;
  flex: 1;
  text-align: center;
  box-shadow: var(--card-shadow);
}

.stat-card h3 {
  color: var(--primary-color);
  font-size: 18px;
  margin-bottom: 10px;
}

.stat-card p {
  font-size: 24px;
  font-weight: bold;
  color: var(--secondary-color);
}

/* 카드 개선 */
.card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
}

.card-header time {
  color: #666;
  font-size: 14px;
}

.card-content h3 {
  font-size: 18px;
  color: var(--primary-color);
  margin: 15px 0 10px;
}

.learn-contents {
  margin-left: 0;
}

.learn-contents li {
  list-style-type: none;
  margin: 8px 0;
  padding-left: 20px;
  position: relative;
}

.learn-contents li::before {
  content: "•";
  position: absolute;
  left: 0;
  color: var(--secondary-color);
}

.link-icon {
  font-size: 12px;
  margin-left: 4px;
}

/* 태그 스타일 */
.card-tags {
  margin-top: 15px;
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.tag {
  background-color: var(--light-gray);
  padding: 4px 8px;
  border-radius: 4px;
  font-size: 12px;
  color: var(--primary-color);
}

/* 반응형 개선 */
@media screen and (max-width: 768px) {
  .search-container {
    flex-direction: column;
  }

  #searchInput {
    width: 100%;
  }

  .stats-container {
    flex-direction: column;
  }
}

/* imp2 */
.section-content {
  margin: 15px 0;
  padding: 15px;
  background-color: #f8f9fa;
  border-radius: 6px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
}

.card-content h3 {
  margin-top: 25px;
  margin-bottom: 10px;
  color: #2c3e50;
  font-size: 1.1em;
}

.learn-contents {
  list-style-type: none;
  margin: 0;
  padding: 0;
}

.learn-contents li {
  margin: 8px 0;
  padding-left: 20px;
  position: relative;
}

.learn-contents li::before {
  content: "•";
  position: absolute;
  left: 0;
  color: #2980b9;
}

.reflection {
  border-left: 4px solid #ffd700;
  background-color: #fff9e6;
}

.reflection p {
  margin: 8px 0;
}

.trouble-shooting {
  border-left: 4px solid #e74c3c;
  background-color: #fef5f5;
}

.trouble-shooting details {
  margin: 5px 0;
}

.trouble-shooting summary {
  cursor: pointer;
  color: #c0392b;
  font-weight: 500;
}

.trouble-shooting details[open] summary {
  margin-bottom: 10px;
}

.next-plan {
  border-left: 4px solid #2ecc71;
  background-color: #f0fff4;
}

.next-plan ul {
  list-style-type: none;
  padding-left: 0;
}

.next-plan li {
  margin: 8px 0;
  padding-left: 20px;
  position: relative;
}

.next-plan li::before {
  content: "→";
  position: absolute;
  left: 0;
  color: #27ae60;
}

.references ul {
  list-style-type: none;
  padding-left: 0;
}

.references li {
  margin: 5px 0;
}

.references a {
  color: #2980b9;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
}

.references a:hover {
  text-decoration: underline;
}

.tag.difficulty-easy {
  background-color: #d5f5e3;
  color: #27ae60;
}

.tag.difficulty-medium {
  background-color: #fdebd0;
  color: #f39c12;
}

.tag.difficulty-hard {
  background-color: #fadbd8;
  color: #c0392b;
}

.tag[class*="time-"] {
  background-color: #ebf5fb;
  color: #2980b9;
}

/* 반응형 디자인 보완 */
@media screen and (max-width: 768px) {
  .section-content {
    padding: 12px;
  }

  .card-content h3 {
    font-size: 1em;
  }

  .tag {
    font-size: 11px;
    padding: 3px 6px;
  }
}