:root {
  --primary-gradient: linear-gradient(135deg, #ff6b6b 0%, #4facfe 100%);
  --soft-blue: #e3f2fd;
  --deep-blue: #003399;
  --text-color: #2d3436;
  --primary-color: #ff6b6b;
  --secondary-color: #4facfe;
  --bg-gradient: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
}

body {
  font-family: "Quicksand", sans-serif;
  margin: 0;
  color: var(--text-color);
  line-height: 1.8;
  margin: 0;
  background: var(--bg-gradient);
  color: #2d3436;
  scroll-behavior: smooth;
  background: linear-gradient(180deg, #6666ff 0%, #ffccff 50%, #99ccff 100%);
}



header h1 {
  font-family: "Dancing Script", cursive;
  font-size: 4rem;
  margin: 0;
  text-shadow: 2px 2px 10px rgba(0, 0, 0, 0.3);
}

/* Container nội dung chính */
.container {
  max-width: 900px;
  margin: -50px auto 100px;
  padding: 40px;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(10px);
  border-radius: 30px;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.1);
  position: relative;
  z-index: 10;
}

.header-title {
  font-size: 2.5rem;
  font-weight: 700;
  text-align: center;
  background: var(--primary-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 10px;
  text-transform: uppercase;
  background-clip: text;
}

.item-desc {
  font-size: 1.1rem;
  color: #444;
  text-align: justify;
  margin-bottom: 30px;
  position: relative;
  padding: 10px 0;
}

/* Style đặc biệt cho phần Sapo (mô tả đầu tiên) */
.container > .item-desc:first-of-type {
  font-style: italic;
  text-align: center;
  font-size: 1.3rem;
  color: var(--deep-blue);
  font-weight: 600;
  border-bottom: 2px solid var(--soft-blue);
  padding-bottom: 20px;
}

/* Box chứa ảnh */
.item-box {
  width: 100%;
  margin: 40px 0;
  border-radius: 20px;
  overflow: hidden;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
  transition: transform 0.3s ease;
  background: #f8f9fa;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 400px; /* Chiều cao giả định cho ảnh */
  border: 1px dashed #ccc;
}

.item-box img {
  width: 100%;
  height: auto;
  display: block;
  transition: 0.5s;
}

.item-box:hover {
  transform: scale(1.02);
}

/* Countdown nhỏ để đồng bộ vibe */
.countdown-mini {
  display: flex;
  justify-content: center;
  gap: 15px;
  margin-top: 20px;
}
.time-unit {
  background: rgba(255, 255, 255, 0.2);
  padding: 5px 15px;
  border-radius: 10px;
  font-weight: bold;
}

/* Nút quay lại */
.back-btn {
  position: fixed;
  top: 20px;
  left: 20px;
  background: white;
  color: var(--primary-color);
  padding: 10px 20px;
  border-radius: 50px;
  text-decoration: none;
  font-weight: bold;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
  z-index: 1000;
  transition: 0.3s;
}
.back-btn:hover {
  background: #ff6b6b;
  color: white;
}
@media (max-width: 768px) {
  .container {
    margin: -30px 15px 50px;
    padding: 20px;
  }
  header h1 {
    font-size: 2.5rem;
  }
  .header-title {
    font-size: 1.8rem;
  }
}
/* ============ NAVBAR ============ */
.main-nav {
  background: rgba(255, 255, 255, 0.95);
  padding: 10px 30px;
  position: fixed;
  width: 100%;
  top: 0;
  z-index: 1000;
  box-shadow: 0 2px 15px rgba(0, 0, 0, 0.1);
  display: flex;
  align-items: center;
  justify-content: space-between;
  backdrop-filter: blur(10px);
  border-bottom: 2px solid var(--primary-color);
}

/* Logo container - nằm trong nav */
.nav-logo-container {
  display: flex;
  align-items: center;
  gap: 15px;
  text-decoration: none;
  transition: transform 0.3s;
}

.nav-logo-container:hover {
  transform: scale(1.05);
}

.nav-logo-img {
  height: 50px;
  width: 50px;
  border-radius: 50%;
  border: 3px solid var(--primary-color);
  padding: 2px;
  object-fit: cover;
  box-shadow: 0 4px 10px rgba(255, 107, 107, 0.3);
}

.nav-logo-text {
  display: flex;
  flex-direction: column;
}

.nav-logo-main {
  font-family: "Dancing Script", cursive;
  font-size: 28px;
  font-weight: 700;
  color: var(--primary-color);
  line-height: 1;
}

.nav-logo-sub {
  font-size: 12px;
  color: #666;
  font-style: italic;
  margin-top: 2px;
}

/* Menu - nằm trong nav */
.nav-menu {
  display: flex;
  list-style: none;
  gap: 25px;
  margin: 0;
  padding: 0;
}

.nav-menu li {
  position: relative;
}

.nav-menu a {
  text-decoration: none;
  color: #333;
  font-weight: 600;
  padding: 8px 16px;
  border-radius: 25px;
  transition: all 0.3s;
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-menu a:hover {
  color: var(--primary-color);
  background: rgba(255, 107, 107, 0.1);
}

.nav-menu a.active {
  background: linear-gradient(to right, #ff6b6b, #ff8e8e);
  color: white;
  box-shadow: 0 4px 10px rgba(255, 107, 107, 0.3);
}

/* Mobile menu toggle - nằm trong nav - ĐÃ SỬA THIẾU } */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 24px;
  color: var(--primary-color);
  cursor: pointer;
}

/* ============ HERO SECTION ============ */
header {
  height: 100vh;
  background:
    linear-gradient(45deg, rgba(255, 107, 107, 0.6), rgba(79, 172, 254, 0.6)),
    url("bia-lop.jpg");
  background-size: cover;
  background-attachment: fixed;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  color: white;
  text-align: center;
  padding-top: 80px;
}

header h1 {
  font-family: "Dancing Script", cursive;
  font-size: 5rem;
  margin: 0;
  animation: fadeIn 2s;
  text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.5);
}

/* Countdown Timer */
.countdown-container {
  background: rgba(255, 255, 255, 0.2);
  backdrop-filter: blur(10px);
  padding: 20px;
  border-radius: 15px;
  margin-top: 20px;
  display: flex;
  gap: 20px;
}

.time-box {
  font-size: 1.5rem;
  font-weight: bold;
  text-align: center;
  min-width: 80px;
}

.time-box span {
  display: block;
  font-size: 2.5rem;
  margin-bottom: 5px;
}

/* ============ CONTENT SECTIONS ============ */
.content-section {
  max-width: 1100px;
  margin: 100px auto;
  padding: 40px;
  background: white;
  border-radius: 20px;
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.05);
}

h2.section-title {
  text-align: center;
  font-size: 2.5rem;
  background: linear-gradient(to right, #ff6b6b, #4facfe);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 40px;
}

/* Gallery Masonry */
.gallery {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 15px;
}

.gallery img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  border-radius: 10px;
  filter: grayscale(30%);
  transition: 0.5s;
  cursor: pointer;
}

.gallery img:hover {
  filter: grayscale(0%);
  transform: scale(1.03);
}

/* Achievements / Timeline */
.timeline {
  border-left: 3px solid var(--secondary-color);
  padding-left: 20px;
  margin-left: 20px;
}

.event {
  margin-bottom: 30px;
  position: relative;
}

.event::before {
  content: "";
  position: absolute;
  left: -31px;
  top: 5px;
  width: 15px;
  height: 15px;
  background: var(--primary-color);
  border-radius: 50%;
}

/* Guestbook Form */
.guestbook textarea {
  width: 100%;
  padding: 15px;
  border-radius: 10px;
  border: 1px solid #ddd;
  margin-bottom: 10px;
  font-family: inherit;
}

.btn-submit {
  background: linear-gradient(to right, #ff6b6b, #ff8e8e);
  color: white;
  border: none;
  padding: 12px 30px;
  border-radius: 25px;
  cursor: pointer;
  font-weight: bold;
  transition: 0.3s;
}

.btn-submit:hover {
  transform: translateY(-3px);
  box-shadow: 0 5px 15px rgba(255, 107, 107, 0.3);
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

footer {
  background: #2d3436;
  color: white;
  text-align: center;
  padding: 50px 0;
  margin-top: 100px;
}

/* ============ RESPONSIVE ============ */
@media (max-width: 768px) {
  .main-nav {
    padding: 10px 20px;
  }

  .nav-toggle {
    display: block;
  }

  .nav-menu {
    position: fixed;
    top: 80px;
    left: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.98);
    flex-direction: column;
    padding: 20px;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
    display: none;
    gap: 15px;
  }

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

  .nav-logo-main {
    font-size: 22px;
  }

  .nav-logo-img {
    height: 40px;
    width: 40px;
  }

  header h1 {
    font-size: 3rem;
  }

  .countdown-container {
    flex-wrap: wrap;
    justify-content: center;
  }

  .time-box {
    min-width: 70px;
  }

  .time-box span {
    font-size: 2rem;
  }
}
/* Style dành riêng cho ô mốc thời gian học đường */
.item-box.schedule-box {
  display: block; /* Chuyển từ flex sang block để nội dung văn bản tự nhiên hơn */
  padding: 0;
  min-height: auto; /* Bỏ chiều cao giả định của ảnh */
  border: none;
  /* Gradient nền nổi bật */
  background: linear-gradient(135deg, #FFF5F5 0%, #F0F4FF 100%) !important;
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.1);
  border-left: 8px solid #ff6b6b; /* Tạo vạch màu nhấn ở bên trái */
}

.item-box.schedule-box .schedule-content {
  padding: 30px;
  text-align: left;
}

.item-box.schedule-box h3 {
  color: #003399;
  font-size: 1.8rem;
  margin-top: 0;
  margin-bottom: 20px;
  font-weight: 700;
}

.item-box.schedule-box ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.item-box.schedule-box li {
  font-size: 1.2rem;
  margin-bottom: 15px;
  line-height: 1.6;
  border-bottom: 1px dashed rgba(0, 0, 0, 0.05);
  padding-bottom: 10px;
}

.item-box.schedule-box li:last-child {
  border-bottom: none;
}

.item-box.schedule-box strong {
  color: #ff6b6b;
}
        .star-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 30px;
            padding: 20px 0;
        }
        .star-card {
            background: white;
            border-radius: 20px;
            overflow: hidden;
            box-shadow: 0 10px 20px rgba(0,0,0,0.1);
            transition: transform 0.3s;
            border: 1px solid #eee;
        }
        .star-card:hover {
            transform: translateY(-10px);
        }
        .star-img-container {
            width: 100%;
            height: 250px;
            background: #f0f4ff;
            display: flex;
            align-items: center;
            justify-content: center;
            position: relative;
            overflow: hidden;
        }
        .star-img-container img {
            width: 100%;
            height: 100%;
            object-fit: cover;
        }
        .star-img-placeholder {
            color: #ccc;
            font-size: 3rem;
        }
        .star-info {
            padding: 20px;
        }
        .star-name {
            font-family: 'Dancing Script', cursive;
            font-size: 1.8rem;
            color: var(--primary-color);
            margin-bottom: 5px;
        }
        .star-title {
            font-weight: 600;
            color: var(--deep-blue);
            font-size: 1rem;
            margin-bottom: 15px;
            display: block;
        }
        .star-awards {
            background: var(--soft-blue);
            padding: 10px;
            border-radius: 10px;
            font-size: 0.9rem;
        }
        .star-awards ul {
            padding-left: 20px;
            margin: 5px 0;
        }