body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 20px;
    text-align: center;
    color: #333;
    height: 100vh;
    width: 100%;
}

.login-bg {
    background-repeat: no-repeat;
    background-position: center center;
    background-attachment: fixed;
    background-size: cover !important;
}

video {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    z-index: -1;
}

h1 {
    font-family: 'Nanum Gothic', sans-serif;
    font-size: 2.5em;
    color: #fff;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.5);
    margin-top: 100px;
    margin-bottom: 10px;
}

h2 {
    font-family: 'Nanum Gothic', sans-serif;
    font-size: 1.8em;
    color: #fff;
    text-shadow: 1px 1px 3px rgba(0, 0, 0, 0.5);
    margin-bottom: 20px;
}

#loginForm {
    background: rgba(255, 255, 255, 0.9);
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    max-width: 400px;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

input, button {
    width: 100%;
    padding: 10px;
    margin: 10px 0;
    border: 1px solid #ddd;
    border-radius: 5px;
    box-sizing: border-box;
}

button {
    background-color: #2ecc71;
    color: white;
    border: none;
    cursor: pointer;
    transition: background-color 0.3s;
}

button:hover {
    background-color: #27ae60;
}

#teacher-section {
    display: none;
    max-width: 1200px;
    margin: 0 auto;
    position: relative;
    height: 100%;
    width: 100%;
}

/* 버튼 그리드 레이아웃 */
.button-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    grid-template-rows: repeat(2, 1fr);
    gap: 30px;
    max-width: 1000px;
    margin: 100px auto 0;
    justify-content: center;
}

.album-btn {
    text-decoration: none;
    transition: transform 0.3s;
    display: block;
}

.album-btn img {
    width: 150px;
    height: 150px;
    object-fit: cover;
    border: none;
    border-radius: 50%;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

.album-btn:hover {
    transform: scale(1.1);
}

/* 이전 개별 버튼 위치 스타일 제거 */
/* #btn-album, #btn-program, #btn-room, #btn-task, #btn-travel, #btn-survey 스타일 삭제 */

#modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    justify-content: center;
    align-items: center;
}

#modal img, #modal video {
    max-width: 80%;
    max-height: 80%;
}

#modal button {
    position: absolute;
    top: 20px;
    right: 20px;
    width: auto;
    padding: 10px 20px;
}

#modal .back-btn {
    position: absolute;
    top: 10px;
    right: 10px;
    width: auto !important;
    padding: 5px 10px !important;
    font-size: 1em;
    color: white;
    background-color: #e74c3c;
    border: none;
    cursor: pointer;
    z-index: 10;
}

#program-section, #room-section, #travel-section {
    display: none;
    position: relative;
    max-width: 900px;
    margin: 0 auto;
    background: rgba(255, 255, 255, 0.9);
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    text-align: center;
}

#program-section h2, #room-section h2, #travel-section h2 {
    font-family: 'Nanum Gothic', sans-serif;
    font-size: 2em;
    color: #6b48ff;
    text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.3);
    margin-bottom: 20px;
}

#program-section .prep-list, #room-section .prep-list {
    text-align: left;
    margin-top: 20px;
    padding-left: 20px;
}

#program-section button, #room-section button, #travel-section button {
    margin-top: 30px;
    background-color: #e74c3c;
}

#room-section table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
    font-size: 1em;
}

#room-section th, #room-section td {
    border: 1px solid #ddd;
    padding: 12px;
    text-align: center;
    vertical-align: middle;
}

#room-section th {
    background-color: #6b48ff;
    color: white;
    font-weight: bold;
}

#room-section td {
    background-color: #f9f9f9;
}

/* 반별 색상 구분 */
#room-section tr.class-12 td {
    background-color: #e6f0fa; /* 연한 파란색 */
}

#room-section tr.class-11 td {
    background-color: #e6f4e6; /* 연한 초록색 */
}

#room-section tr.class-10 td {
    background-color: #fffbe6; /* 연한 노란색 */
}

#room-section tr.class-9 td {
    background-color: #ffefdb; /* 연한 주황색 */
}

#room-section tr.class-8 td {
    background-color: #f0e6f4; /* 연한 보라색 */
}

#room-section tr.class-7 td {
    background-color: #ffe6e6; /* 연한 분홍색 */
}

#room-section tr.class-1 td {
    background-color: #e6faff; /* 연한 하늘색 */
}

#room-section tr.class-2 td {
    background-color: #f0f4e6; /* 연한 연두색 */
}

#room-section tr.class-3 td {
    background-color: #fff5e6; /* 연한 살구색 */
}

#room-section tr.class-4 td {
    background-color: #ffe6f0; /* 연한 핑크 */
}

#room-section tr.class-5 td {
    background-color: #e6f0e6; /* 연한 민트 */
}

#room-section tr.class-6 td {
    background-color: #f0e6ff; /* 연한 라벤더 */
}

/* 담당 반 강조 스타일 */
#room-section tr.highlight td {
    font-size: 1.2em;
    color: #000080; /* 남색 */
    background-color: #d3d3d3 !important; /* 더 진한 회색 */
    border: 2px solid #000080; /* 남색 테두리 */
}

/* 여행지 카드 스타일 */
.travel-container {
    display: flex;
    justify-content: space-around;
    flex-wrap: wrap;
    gap: 20px;
    margin: 20px 0;
}

.travel-card {
    width: 250px;
    background: #fff;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
    overflow: hidden;
    text-decoration: none;
    color: #333;
    transition: transform 0.3s ease;
}

.travel-card:hover {
    transform: translateY(-5px);
}

.travel-card img {
    width: 100%;
    height: 150px;
    object-fit: cover;
}

.travel-card h3 {
    font-family: 'Nanum Gothic', sans-serif;
    font-size: 1.2em;
    margin: 10px 0;
    color: #6b48ff;
}

.travel-card p {
    font-size: 0.9em;
    margin: 0 10px 10px;
    color: #666;
}

/* 반응형 디자인을 위한 미디어 쿼리 */
@media (max-width: 1200px) {
    .button-grid {
        grid-template-columns: repeat(3, 1fr);
        grid-template-rows: repeat(3, 1fr);
    }
}

@media (max-width: 900px) {
    .button-grid {
        grid-template-columns: repeat(2, 1fr);
        grid-template-rows: repeat(4, 1fr);
    }
}

@media (max-width: 600px) {
    .button-grid {
        grid-template-columns: 1fr;
        grid-template-rows: repeat(8, 1fr);
    }
    
    .album-btn img {
        width: 120px;
        height: 120px;
    }
}