/* ========== 기본 설정 ========== */
* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: "Noto Sans KR", sans-serif;
  margin: 0;
  background-color: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

/* =============================== */
/* ========== 컬러 테마 ========== */
/* =============================== */
:root {
  --main: #00c2b2;
  --main-dark: #008e82;
  --dark: #2c3e50;
  --bg: #f9fbfb;
  --text: #333;
  --gray: #bdc3c7;
}

/* ========== 레이아웃 ========== */
.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 20px;
}

/* =============================== */
/* ========== 헤더 ========== */
/* =============================== */
header {
  background-color: var(--dark);
  color: white;
  padding: 1rem 0;
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.flex-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

header h1 {
  margin: 0;
  font-size: 1.2rem;
  letter-spacing: 1px;
}

/* 네비게이션 */
nav ul {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  gap: 20px;
}

nav a {
  color: var(--gray);
  text-decoration: none;
  font-weight: 500;
  transition: 0.25s;
}

nav a:hover,
nav a.active {
  color: var(--main);
  font-weight: 700;
  border-bottom: 2px solid var(--main);
  padding-bottom: 3px;
}

/* =============================== */
/* ========== 배너 ========== */
/* =============================== */
.banner {
  background: linear-gradient(135deg, var(--main) 0%, var(--main-dark) 100%);
  color: white;
  text-align: center;
  padding: 80px 20px;
}

.banner h2 {
  font-size: 2.2rem;
  margin-bottom: 10px;
}

/* =============================== */
/* ========== 홈 소개 섹션 ========== */
/* =============================== */
.intro {
  text-align: center;
  padding: 60px 20px;
}

.avatar-circle {
  width: 120px;
  height: 120px;
  background: white;
  border-radius: 50%;
  margin: 0 auto 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 60px;
  box-shadow: 0 10px 25px rgba(0,0,0,0.05);
}

.tag-cloud {
  display: flex;
  justify-content: center;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 20px;
}

.tag {
  background: white;
  padding: 5px 15px;
  border-radius: 20px;
  font-size: 0.85rem;
  color: #666;
  border: 1px solid #eee;
}

.music-box {
  margin-top: 30px;
  background: #f1f1f1;
  padding: 15px 25px;
  border-radius: 30px;
  display: inline-block;
}

/* =============================== */
/* ========== 시간표 ========== */
/* =============================== */
.main-schedule {
  padding: 60px 0;
}

.section-title {
  text-align: center;
  margin-bottom: 30px;
}

.table-wrapper {
  overflow-x: auto;
  background: white;
  padding: 20px;
  border-radius: 20px;
  box-shadow: 0 5px 20px rgba(0,0,0,0.05);
}

.timetable {
  width: 100%;
  border-collapse: collapse;
  text-align: center;
}

.timetable th {
  padding: 15px;
  background: #fafafa;
  border-bottom: 2px solid var(--main);
}

.timetable td {
  padding: 15px;
  border: 1px solid #f3f3f3;
  font-size: 13px;
}

/* 과목 색상 */
.bg-embedded { background-color: #e3f2fd; color: #1976d2; font-weight: bold; }
.bg-english  { background-color: #f1f8e9; color: #388e3c; font-weight: bold; }
.bg-oss      { background-color: #fff3e0; color: #f57c00; font-weight: bold; }
.bg-algo     { background-color: #f3e5f5; color: #7b1fa2; font-weight: bold; }
.bg-ent      { background-color: #e0f2f1; color: #00796b; font-weight: bold; }
.bg-csi      { background-color: #ffebee; color: #d32f2f; font-weight: bold; }

/* =============================== */
/* ========== 카드 섹션 ========== */
/* =============================== */
.cards-section {
  padding-bottom: 80px;
}

.cards {
  display: flex;
  justify-content: center;
  gap: 30px;
  flex-wrap: wrap;
}

.card {
  background: white;
  padding: 40px;
  border-radius: 20px;
  width: 300px;
  text-align: center;
  transition: 0.3s;
  box-shadow: 0 20px 40px rgba(0,0,0,0.05);
}

.card:hover {
  transform: translateY(-10px) scale(1.03);
}

.card-icon {
  font-size: 3rem;
  margin-bottom: 15px;
}

.btn {
  display: inline-block;
  margin-top: 15px;
  padding: 10px 25px;
  background: var(--main);
  color: white !important;
  text-decoration: none;
  border-radius: 25px;
  transition: 0.3s;
  box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

.btn:hover {
  background: var(--main-dark);
  transform: translateY(-3px);
  box-shadow: 0 8px 20px rgba(0,0,0,0.15);
}

/* =============================== */
/* ========== 페이지 공통 이미지 효과 ========== */
/* =============================== */
img,
video {
  transition: 0.3s ease;
}

img:hover,
.photo-card img:hover {
  transform: scale(1.02);
}

/* =============================== */
/* ========== 취미 페이지 ========== */
/* =============================== */
.hobby-content {
  padding: 40px 20px;
}

.youtube-container {
  margin-bottom: 30px;
  border-radius: 10px;
  overflow: hidden;
  box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

.guitar-photos {
  display: flex;
  gap: 20px;
  justify-content: center;
}

.guitar-photos img {
  width: calc(50% - 10px);
  border-radius: 8px;
  box-shadow: 0 4px 10px rgba(0,0,0,0.1);
}

/* 모바일 전환 */
@media (max-width: 768px) {
  .guitar-photos {
    flex-direction: column;
  }
  .guitar-photos img {
    width: 100%;
  }
}

/* =============================== */
/* ========== 군생활 페이지 ========== */
/* =============================== */
.photo-card video {
  width: 100%;
  height: 200px;
  object-fit: cover;
  border-radius: 5px;
  background-color: #000;
}

/* =============================== */
/* ========== 구분선 & 푸터 ========== */
/* =============================== */
.divider {
  border: 0;
  height: 1px;
  background: #eee;
  margin: 40px auto;
}

footer {
  text-align: center;
  background-color: var(--dark);
  color: var(--gray);
  padding: 30px;
  font-size: 14px;
}