:root {
    --primary: #FF7043; /* 따뜻하고 에너제틱한 오렌지 톤 */
    --primary-hover: #F4511E;
    --bg-color: #FFF9F5; /* 포근한 크림색 배경 */
    --card-bg: #FFFFFF;
    --text-main: #2C2C2C;
    --text-muted: #7A7A7A;
    --border: #E8E8E8;
    --shadow: 0 12px 40px rgba(255, 112, 67, 0.06); /* 부드러운 웜톤 그림자 */
    --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

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

body {
    font-family: 'Pretendard', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.6;
    overflow-x: hidden;
}

header {
    padding: 24px 40px;
}

.logo {
    font-size: 24px;
    font-weight: 800;
    color: var(--primary);
}

main {
    max-width: 900px;
    margin: 0 auto;
    padding: 20px;
}

.hero-section {
    text-align: center;
    margin-top: 30px;
    margin-bottom: 60px;
}

.hero-section h1 {
    font-size: 42px;
    font-weight: 800;
    margin-bottom: 12px;
    color: var(--primary);
    letter-spacing: -1px;
}

.hero-section p {
    font-size: 18px;
    color: var(--text-muted);
    margin-bottom: 40px;
}

/* --- 검색 카드 UI --- */
.search-card {
    background: var(--card-bg);
    border-radius: 24px;
    padding: 35px;
    box-shadow: var(--shadow);
    text-align: left;
}

.tabs-container {
    display: flex;
    gap: 12px;
    margin-bottom: 24px;
    border-bottom: 2px solid #F5F5F5;
    padding-bottom: 15px;
    /* 모바일 가로 스크롤 매끄럽게 처리 */
    overflow-x: auto;
    scrollbar-width: none;
    -webkit-overflow-scrolling: touch;
}

.tabs-container::-webkit-scrollbar {
    display: none;
}

.tab-btn {
    background: transparent;
    border: none;
    font-size: 16px;
    font-weight: 700;
    color: var(--text-muted);
    padding: 12px 24px;
    cursor: pointer;
    border-radius: 30px;
    transition: var(--transition);
    white-space: nowrap;
}

.tab-btn i {
    margin-right: 8px;
}

.tab-btn:hover {
    color: var(--primary);
    background: #FFF0EB;
}

.tab-btn.active {
    color: #fff;
    background: var(--primary);
    box-shadow: 0 4px 15px rgba(255, 112, 67, 0.3);
}

.tab-pane {
    display: none;
    animation: fadeIn 0.4s ease;
}

.tab-pane.active {
    display: block;
}

.form-row {
    margin-bottom: 20px;
}

.trip-type {
    display: flex;
    gap: 24px;
    font-weight: 600;
    margin-bottom: 24px;
    color: var(--text-main);
}

.trip-type label {
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 6px;
}

/* 엑센트 컬러 라디오 버튼 */
.trip-type input[type="radio"] {
    accent-color: var(--primary);
    width: 18px;
    height: 18px;
}

.multi-input {
    display: flex;
    gap: 15px;
    align-items: center;
}

.input-group {
    flex: 1;
    display: flex;
    flex-direction: column;
}

.input-group label {
    font-size: 13px;
    color: var(--text-muted);
    margin-bottom: 8px;
    font-weight: 700;
}

.input-group input, .input-group select {
    padding: 18px;
    border: 1px solid var(--border);
    border-radius: 16px;
    font-size: 16px;
    font-weight: 500;
    font-family: inherit;
    transition: var(--transition);
    background: #FAFAFA;
}

.input-group input:focus, .input-group select:focus {
    outline: none;
    border-color: var(--primary);
    background: #FFF;
    box-shadow: 0 0 0 4px rgba(255, 112, 67, 0.1);
}

.swap-icon {
    width: 44px;
    height: 44px;
    background: #FFF0EB;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary);
    cursor: pointer;
    margin-top: 24px;
    transition: var(--transition);
}

.swap-icon:hover {
    transform: rotate(180deg);
}

.search-btn {
    width: 100%;
    padding: 20px;
    margin-top: 10px;
    border: none;
    background: var(--primary);
    color: #fff;
    font-size: 18px;
    font-weight: 800;
    border-radius: 16px;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: 0 8px 20px rgba(255, 112, 67, 0.25);
}

.search-btn:hover {
    background: var(--primary-hover);
    transform: translateY(-3px);
    box-shadow: 0 12px 25px rgba(255, 112, 67, 0.35);
}

/* --- 로딩 애니메이션 --- */
.loading-container {
    text-align: center;
    margin: 60px 0;
}
.loading-container.hidden {
    display: none;
}
.spinner {
    width: 50px; height: 50px;
    border: 4px solid #FFEBE3;
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 1s infinite cubic-bezier(0.55, 0.15, 0.45, 0.85);
    margin: 0 auto 20px;
}
@keyframes spin { 100% { transform: rotate(360deg); } }

/* --- 결과 영역 --- */
.results-section {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.7s cubic-bezier(0.25, 0.8, 0.25, 1);
}

.results-section.show {
    opacity: 1;
    transform: translateY(0);
}

.results-section.hidden {
    display: none;
}

.result-header {
    text-align: center;
    margin-bottom: 40px;
}

.result-header h2 {
    font-size: 32px;
    font-weight: 800;
    margin-bottom: 8px;
}

.result-header .highlight {
    color: var(--primary);
}

.chart-card {
    background: var(--card-bg);
    border-radius: 24px;
    padding: 30px;
    box-shadow: var(--shadow);
    margin-bottom: 40px;
}

.chart-card h3 {
    margin-bottom: 20px;
    font-size: 20px;
}

.chart-wrapper {
    height: 280px;
    position: relative;
    width: 100%;
}

.recommendations h3 {
    font-size: 22px;
    margin-bottom: 20px;
}

.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 20px;
}

.flight-card {
    background: var(--card-bg);
    border-radius: 20px;
    padding: 24px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 2px solid transparent;
    cursor: pointer;
}

.flight-card:hover {
    transform: translateY(-8px);
    border-color: var(--primary);
}

.flight-card-header {
    display: flex;
    justify-content: space-between;
    margin-bottom: 16px;
    color: var(--text-muted);
    font-size: 14px;
    font-weight: 600;
}

.flight-card-route {
    font-size: 20px;
    font-weight: 800;
    margin-bottom: 12px;
    color: var(--text-main);
}

.flight-card-price {
    font-size: 26px;
    font-weight: 800;
    color: var(--primary);
    margin-bottom: 16px;
}

.flight-card-tag {
    display: inline-block;
    padding: 8px 14px;
    background: #FFF0EB;
    color: var(--primary);
    border-radius: 10px;
    font-size: 13px;
    font-weight: 800;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* 모바일 반응형 완벽 처리 */
@media (max-width: 768px) {
    .multi-input {
        flex-direction: column;
        gap: 15px;
    }
    
    .swap-icon {
        transform: rotate(90deg);
        margin: -5px 0 -5px 0;
    }
    .swap-icon:hover {
        transform: rotate(270deg);
    }
    
    .hero-section h1 { font-size: 32px; }
    .result-header h2 { font-size: 26px; }
}

/* --- 푸터 (공지사항) --- */
.affiliate-footer {
    text-align: center;
    padding: 30px 20px;
    margin-top: 40px;
    font-size: 13px;
    color: #a0a0a0;
    background: transparent;
    border-top: 1px solid var(--border);
}

.affiliate-footer p {
    margin: 0;
    line-height: 1.5;
}