@import url('https://fonts.googleapis.com/css2?family=Jua&family=Nanum+Gothic:wght@400;700&display=swap');

:root {
    --bg-color: #f4f6fa;
    --sidebar-bg: #ffffff;
    --text-color: #333333;
    --text-muted: #888888;
    --primary-color: #a8e6cf;       /* 파스텔 민트 */
    --primary-dark: #8cd3b8;
    --secondary-color: #a8d8ea;     /* 파스텔 블루 */
    --secondary-dark: #8fc2d5;
    --danger-color: #ff8b94;        /* 파스텔 핑크 */
    --danger-dark: #e5767f;
    --accent-color: #ffd3b6;        /* 파스텔 오렌지 */
    --card-bg: #ffffff;
    --card-border: #e3e8f0;
    --empty-card-bg: #f8f9fa;
    --empty-card-border: #dee2e6;
    --empty-card-text: #adb5bd;
    
    --transition-speed: 0.3s;
}

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

body {
    font-family: 'Nanum Gothic', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    overflow: hidden;
    height: 100vh;
}

/* 폰트 적용 */
h1, h2, h3, button, .teacher-desk, .seat-card {
    font-family: 'Jua', sans-serif;
    letter-spacing: 0.5px;
}

/* 메인 애플리케이션 컨테이너 */
.app-container {
    display: flex;
    height: 100vh;
    width: 100vw;
    position: relative;
    overflow: hidden;
}

/* 설정 패널 (사이드바) */
.sidebar {
    width: 340px;
    background-color: var(--sidebar-bg);
    border-right: 2px solid #eaeef2;
    padding: 25px;
    display: flex;
    flex-direction: column;
    z-index: 100;
    position: relative;
    transition: transform var(--transition-speed) cubic-bezier(0.25, 0.8, 0.25, 1);
    box-shadow: 5px 0 15px rgba(0, 0, 0, 0.02);
}

/* 사이드바 접힌 상태 */
.sidebar.collapsed {
    transform: translateX(-340px);
}

.sidebar-content {
    display: flex;
    flex-direction: column;
    height: 100%;
    overflow-y: auto;
}

/* 스크롤바 커스텀 */
.sidebar-content::-webkit-scrollbar {
    width: 6px;
}
.sidebar-content::-webkit-scrollbar-thumb {
    background-color: #e2e8f0;
    border-radius: 3px;
}

.sidebar h2 {
    font-size: 1.8rem;
    color: #4a5568;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 8px;
    border-bottom: 3px solid var(--accent-color);
    padding-bottom: 10px;
}

/* 접기/펼치기 버튼 */
.toggle-btn {
    position: absolute;
    right: -24px;
    top: 50%;
    transform: translateY(-50%);
    width: 24px;
    height: 60px;
    background-color: var(--sidebar-bg);
    border: 2px solid #eaeef2;
    border-left: none;
    border-radius: 0 12px 12px 0;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 5px 2px 10px rgba(0, 0, 0, 0.05);
    z-index: 101;
    outline: none;
    transition: background-color 0.2s;
}

.toggle-btn:hover {
    background-color: #f7fafc;
}

.toggle-icon {
    font-size: 0.8rem;
    color: #a0aec0;
    transition: transform var(--transition-speed);
}

.sidebar.collapsed .toggle-icon {
    transform: rotate(180deg);
}

/* 입력 그룹 */
.input-group {
    margin-bottom: 20px;
    display: flex;
    flex-direction: column;
}

.input-group label {
    font-weight: bold;
    font-size: 0.95rem;
    color: #4a5568;
    margin-bottom: 8px;
}

.input-group .sub-label {
    font-weight: normal;
    font-size: 0.8rem;
    color: var(--text-muted);
}

/* 텍스트 영역 */
textarea {
    width: 100%;
    border: 2px solid #e2e8f0;
    border-radius: 12px;
    padding: 12px;
    font-family: inherit;
    font-size: 0.95rem;
    line-height: 1.5;
    resize: none;
    outline: none;
    transition: border-color 0.2s, box-shadow 0.2s;
}

textarea:focus {
    border-color: var(--secondary-color);
    box-shadow: 0 0 0 3px rgba(168, 216, 234, 0.4);
}

/* 행/열 한 줄로 배치 */
.row-col-inputs {
    display: flex;
    gap: 15px;
}

.input-group.half {
    flex: 1;
}

input[type="number"] {
    width: 100%;
    border: 2px solid #e2e8f0;
    border-radius: 12px;
    padding: 10px;
    font-family: 'Jua', sans-serif;
    font-size: 1.1rem;
    text-align: center;
    outline: none;
    transition: border-color 0.2s, box-shadow 0.2s;
}

input[type="number"]:focus {
    border-color: var(--secondary-color);
    box-shadow: 0 0 0 3px rgba(168, 216, 234, 0.4);
}

/* 정보 표시 박스 */
.info-box {
    background-color: #f7fafc;
    border: 1.5px solid #edf2f7;
    border-radius: 12px;
    padding: 12px;
    margin-bottom: 20px;
    display: flex;
    justify-content: space-between;
    font-size: 0.85rem;
    font-weight: bold;
    color: #718096;
}

/* 버튼 스타일 */
.button-group {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin-top: auto;
}

button {
    border: none;
    border-radius: 15px;
    padding: 14px 20px;
    font-size: 1.1rem;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
}

button:active {
    transform: translateY(2px);
    box-shadow: 0 2px 3px rgba(0, 0, 0, 0.05);
}

.primary-btn {
    background-color: var(--primary-color);
    color: #2c5282;
    font-size: 1.2rem;
    font-weight: bold;
}
.primary-btn:hover {
    background-color: var(--primary-dark);
}

.secondary-btn {
    background-color: var(--secondary-color);
    color: #2b6cb0;
    font-weight: bold;
}
.secondary-btn:hover {
    background-color: var(--secondary-dark);
}

.danger-btn {
    background-color: var(--danger-color);
    color: #742a2a;
    font-size: 0.95rem;
    padding: 10px;
}
.danger-btn:hover {
    background-color: var(--danger-dark);
}

/* 메인 영역 */
.main-content {
    flex: 1;
    padding: 30px;
    display: flex;
    flex-direction: column;
    overflow-y: auto;
    transition: margin-left var(--transition-speed) ease;
}

/* 헤더 영역 */
.main-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 10px;
    border-bottom: 2px solid #edf2f7;
    padding-bottom: 8px;
}

.logo-area {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo-emoji {
    font-size: 1.6rem;
}

.main-header h1 {
    font-size: 1.6rem;
    color: #2d3748;
}

.header-buttons {
    display: flex;
    gap: 10px;
    align-items: center;
}

.mode-change-btn {
    background-color: #f0f4ff;
    border: 2px solid #c3dafe;
    color: #4c51bf;
    padding: 8px 16px;
    font-size: 0.95rem;
    border-radius: 12px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.02);
    font-weight: bold;
    transition: all 0.2s ease;
}

.mode-change-btn:hover {
    background-color: #ebf8ff;
    border-color: #a3bffa;
}

.icon-btn {
    background-color: #ffffff;
    border: 2px solid #e2e8f0;
    color: #4a5568;
    padding: 8px 16px;
    font-size: 0.95rem;
    border-radius: 12px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.02);
}
.icon-btn:hover {
    background-color: #f7fafc;
    border-color: #cbd5e0;
}

/* 교실 칠판/교탁 표시 */
.classroom-front {
    display: flex;
    justify-content: center;
    margin-bottom: 12px;
}

.teacher-desk {
    background-color: var(--accent-color);
    color: #7b341e;
    font-size: 1.1rem;
    font-weight: bold;
    padding: 6px 40px;
    border-radius: 20px;
    box-shadow: 0 4px 6px rgba(255, 211, 182, 0.2);
    border: 2px solid #fbd38d;
    letter-spacing: 4px;
    position: relative;
    user-select: none;
}

/* 자리 컨테이너 */
.seats-container {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 10px;
    overflow-y: auto;
}

.seats-grid {
    display: grid;
    gap: 12px;
    width: 100%;
    max-width: 1100px;
    margin: 0 auto;
    padding-bottom: 15px;
}

/* 자리 카드 공통 */
.seat-card {
    background-color: var(--card-bg);
    border: 3px solid var(--card-border);
    border-radius: 18px;
    padding: 12px 10px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    min-height: 80px;
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.02);
    transition: transform 0.2s, box-shadow 0.2s, border-color 0.2s, background-color 0.2s;
    position: relative;
    cursor: grab;
    user-select: none;
}

.seat-card:active {
    cursor: grabbing;
}

/* 자리 번호 라벨 */
.seat-number {
    position: absolute;
    top: 10px;
    left: 12px;
    font-size: 0.8rem;
    color: var(--text-muted);
    font-family: sans-serif;
    font-weight: normal;
}

/* 학생 이름 */
.student-name {
    font-size: 1.4rem;
    color: #2d3748;
    text-shadow: 1px 1px 0px rgba(255, 255, 255, 0.8);
    word-break: break-all;
}

/* 빈자리 카드 */
.seat-card.empty {
    background-color: var(--empty-card-bg);
    border: 3px dashed var(--empty-card-border);
    cursor: default;
    box-shadow: none;
}

.seat-card.empty:hover {
    transform: none;
    box-shadow: none;
    border-color: var(--empty-card-border);
}

.seat-card.empty .student-name {
    color: var(--empty-card-text);
    font-size: 1.3rem;
}

/* 드래그 앤 드롭 효과 */
.seat-card.dragging {
    opacity: 0.3;
    border-style: dashed;
    border-color: var(--secondary-color);
    transform: scale(0.95);
}

.seat-card.drag-over {
    border-color: var(--secondary-color);
    background-color: #f0f7ff;
    transform: translateY(-4px) scale(1.03);
    box-shadow: 0 12px 20px rgba(168, 216, 234, 0.3);
}

/* 자리 호버 효과 (빈자리가 아닐 때만) */
.seat-card:not(.empty):hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.04);
    border-color: var(--secondary-color);
}

/* 토스트 알림 */
.toast {
    position: fixed;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background-color: #2d3748;
    color: #ffffff;
    padding: 12px 30px;
    border-radius: 30px;
    font-size: 1rem;
    font-weight: bold;
    box-shadow: 0 5px 15px rgba(0,0,0,0.15);
    z-index: 1000;
    opacity: 0;
    transition: transform 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275), opacity 0.3s;
    pointer-events: none;
}

.toast.show {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
}

/* 전체화면일 때 보정 */
:-webkit-full-screen .main-content {
    background-color: var(--bg-color);
    padding: 40px;
}
:-webkit-full-screen .seats-grid {
    max-width: 90%;
}
:-webkit-full-screen .seat-card {
    min-height: 140px;
}
:-webkit-full-screen .student-name {
    font-size: 2.2rem;
}

::backdrop {
    background-color: var(--bg-color);
}

/* 다양한 파스텔 카드 테두리 (랜덤 느낌 부여) */
.seat-card.color-0 { border-color: #ffe5ec; }
.seat-card.color-1 { border-color: #e8f0fe; }
.seat-card.color-2 { border-color: #e6fcf5; }
.seat-card.color-3 { border-color: #fff9db; }
.seat-card.color-4 { border-color: #f3f0ff; }

.seat-card.color-0:hover { border-color: #ffb3c6; }
.seat-card.color-1:hover { border-color: #a8d8ea; }
.seat-card.color-2:hover { border-color: #a8e6cf; }
.seat-card.color-3:hover { border-color: #ffd3b6; }
.seat-card.color-4:hover { border-color: #d8c3ff; }

/* 체크박스 그룹 스타일 */
.checkbox-group {
    display: flex;
    flex-direction: row !important;
    align-items: center;
    gap: 10px;
    margin-bottom: 20px;
    cursor: pointer;
    user-select: none;
}
.checkbox-group input[type="checkbox"] {
    width: 20px;
    height: 20px;
    cursor: pointer;
    accent-color: var(--secondary-dark);
}
.checkbox-group label {
    margin-bottom: 0 !important;
    cursor: pointer;
    font-size: 1.05rem;
    color: #4a5568;
    font-weight: bold;
}

/* 교실 가이드 문구 */
.classroom-guide {
    text-align: center;
    color: var(--text-muted);
    font-size: 0.85rem;
    margin-bottom: 8px;
    font-weight: bold;
    user-select: none;
}

/* 제외된 자리 스타일 (X 표시) */
.seat-card.excluded {
    background-color: #fff5f5;
    border: 3px dashed #feb2b2;
    cursor: pointer;
    box-shadow: none;
}
.seat-card.excluded:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(229, 62, 62, 0.05);
    border-color: #fc8181;
    background-color: #fff0f0;
}
.seat-card.excluded .student-name {
    color: #e53e3e;
    font-size: 1.8rem;
    font-weight: bold;
}
.seat-card.excluded .seat-number {
    color: #feb2b2;
}

/* 그리드 스페이서 (짝꿍 배치 공백) */
.grid-spacer {
    pointer-events: none;
    visibility: hidden;
}

/* 남/여 입력 영역 레이아웃 (gender.html용) */
.gender-inputs {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
}
.gender-inputs .input-group {
    flex: 1;
    margin-bottom: 0;
}
.gender-inputs textarea {
    rows: 10;
}

/* 남학생 전용 자리 스타일 */
.seat-card.boy-seat {
    background-color: #ebf8ff;
    border-color: #90cdf4;
    border-style: dashed;
}
.seat-card.boy-seat:hover {
    border-color: #4299e1;
    background-color: #e6f6ff;
}
.seat-card.boy-seat.empty .student-name {
    color: #3182ce;
    font-size: 1.1rem;
    font-weight: bold;
}

/* 여학생 전용 자리 스타일 */
.seat-card.girl-seat {
    background-color: #fff5f5;
    border-color: #feb2b2;
    border-style: dashed;
}
.seat-card.girl-seat:hover {
    border-color: #f56565;
    background-color: #fff0f0;
}
.seat-card.girl-seat.empty .student-name {
    color: #e53e3e;
    font-size: 1.1rem;
    font-weight: bold;
}

/* 모드 선택 탭 바 스타일 */
.mode-tabs {
    display: flex;
    gap: 6px;
    margin-bottom: 20px;
    background-color: #f0f4f8;
    padding: 4px;
    border-radius: 12px;
    user-select: none;
}
.tab-btn {
    flex: 1;
    padding: 8px 12px;
    font-size: 0.95rem;
    font-weight: bold;
    border-radius: 8px;
    background-color: transparent;
    color: #4a5568;
    box-shadow: none;
    border: none;
    cursor: pointer;
    transition: all 0.2s ease;
}
.tab-btn:hover {
    color: #2b6cb0;
    background-color: rgba(255, 255, 255, 0.4);
}
.tab-btn.active {
    background-color: #ffffff;
    color: #2b6cb0;
    box-shadow: 0 2px 5px rgba(0,0,0,0.06);
}

/* 요소를 숨기기 위한 유틸리티 클래스 */
.hidden {
    display: none !important;
}