/* 기본 스타일 */
body {
    margin: 0;
    padding: 0;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: #f5f7fa;
    color: #2c3e50;
    line-height: 1.6;
}

/* 컨테이너 */
.container {
    max-width: 600px;
    margin: 0 auto;
    padding: 20px;
}

/* 로고 */
.logo {
    text-align: center;
    padding: 40px 0 20px;
}

/* 앱 소개 섹션 */
.app-intro {
	border: none !important;
	max-width: 800px;
	width: 95%;
	margin: 0 auto 3rem;
    /*text-align: center;
    padding: 30px 20px;
    background: white;
    border-radius: 15px;
    margin-bottom: 30px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);*/
}

.app-title {
    font-size: 2.5em;
    color: #2c3e50;
    margin-bottom: 10px;
    font-weight: 700;
}

.app-subtitle {
    font-size: 1.3em;
    color: #7f8c8d;
    margin-bottom: 20px;
}

.app-description {
    color: #34495e;
    font-size: 1.1em;
    line-height: 1.8;
    margin: 0 auto;
}

/* 섹션 기본 스타일 */
.section {
    background: white;
    border-radius: 15px;
    padding: 30px;
    margin-bottom: 30px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.section-title {
    font-size: 1.8em;
    color: #2c3e50;
    margin-bottom: 20px;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 10px;
}

.section-content {
    color: #34495e;
}

/* 다운로드 섹션 */
.download-intro {
    text-align: center;
    margin-bottom: 30px;
    color: #7f8c8d;
}

.download-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
    max-width: 800px;
    margin: 0 auto;
}

.download-button {
    display: inline-flex;
    align-items: center;
    gap: 15px;
    padding: 15px 25px;
    background: linear-gradient(135deg, #ecf0f1 0%, #bdc3c7 100%);
    color: #2c3e50;
    text-decoration: none;
    border-radius: 10px;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.download-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(0,0,0,0.15);
}

.download-button.primary {
   background: linear-gradient(135deg, #3498db 0%, #2980b9 100%);
   color: white;
   font-size: 1.1em;
   padding: 20px 30px;
}

.download-button.primary:hover {
   box-shadow: 0 8px 15px rgba(52, 152, 219, 0.3);
}

.download-button.disabled {
   background: linear-gradient(135deg, #95a5a6 0%, #7f8c8d 100%);
   cursor: not-allowed;
   opacity: 0.7;
   color: white;
}

.download-button.disabled:hover {
   transform: none;
   box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.download-button i {
   font-size: 1.5
}


.download-button.primary {
   background: linear-gradient(135deg, #a8e063 0%, #56ab2f 100%);
   font-size: 1.1em;
   padding: 20px 30px;
}

.download-button.primary:hover {
   box-shadow: 0 8px 15px rgba(86, 171, 47, 0.3);
}

.download-button.disabled {
   background: linear-gradient(135deg, #95a5a6 0%, #7f8c8d 100%);
   cursor: not-allowed;
   opacity: 0.7;
}

.download-button.disabled:hover {
   transform: none;
   box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.download-button i {
   font-size: 1.5em;
}

.button-text {
   display: flex;
   flex-direction: column;
   align-items: flex-start;
}

.button-text small {
   font-size: 0.8em;
   opacity: 0.9;
   font-weight: normal;
}

.system-requirements {
   text-align: center;
   margin-top: 20px;
   color: #7f8c8d;
   font-size: 0.9em;
   padding: 15px;
   background-color: #f8f9fa;
   border-radius: 8px;
}

/* 주요 기능 섹션 */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 25px;
    margin-top: 20px;
    /* 추가적인 너비 제한 없음 */
}

.feature-item {
   text-align: center;
   padding: 25px 20px;
   background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
   border-radius: 12px;
   border: 1px solid #dee2e6;
   transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.feature-item:hover {
   transform: translateY(-5px);
   box-shadow: 0 8px 15px rgba(0,0,0,0.1);
}

.feature-icon {
   font-size: 2.5em;
   color: #3498db;
   margin-bottom: 15px;
}

.feature-item h3 {
   font-size: 1.2em;
   color: #2c3e50;
   margin-bottom: 10px;
   font-weight: 600;
}

.feature-item p {
   color: #7f8c8d;
   font-size: 0.95em;
   line-height: 1.6;
}

/* 버전 섹션 */
.version-item {
   margin-bottom: 20px;
   padding: 20px;
   background: linear-gradient(135deg, #ffffff 0%, #f8f9fa 100%);
   border-radius: 12px;
   border-left: 4px solid #3498db;
   box-shadow: 0 2px 4px rgba(0,0,0,0.05);
   transition: all 0.3s ease;
}

.version-item:hover {
   transform: translateX(5px);
   box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

.version-item.current {
   border-left-color: #27ae60;
   background: linear-gradient(135deg, #f0fff4 0%, #e8f5e8 100%);
}

.version-header {
   display: flex;
   align-items: center;
   gap: 10px;
   margin-bottom: 8px;
}

.version-number {
   font-weight: 700;
   color: #2c3e50;
   font-size: 1.1em;
}

.version-badge {
   padding: 4px 8px;
   border-radius: 15px;
   font-size: 0.75em;
   font-weight: 600;
   text-transform: uppercase;
}

.version-badge.current {
   background-color: #27ae60;
   color: white;
}

.version-badge.beta {
   background-color: #f39c12;
   color: white;
}

.version-date {
   color: #7f8c8d;
   font-size: 0.9em;
   margin-bottom: 12px;
}

.version-changes {
   color: #34495e;
   line-height: 1.6;
}

.change-item {
   margin-bottom: 5px;
   padding-left: 10px;
}

/* 소식 섹션 */
.news-item {
   margin-bottom: 20px;
   padding: 20px;
   background: linear-gradient(135deg, #fff5f5 0%, #ffe8e8 100%);
   border-radius: 12px;
   border-left: 4px solid #e74c3c;
   transition: all 0.3s ease;
}

.news-item:hover {
   transform: translateX(5px);
   box-shadow: 0 4px 8px rgba(231, 76, 60, 0.2);
}

.news-date {
   color: #7f8c8d;
   font-size: 0.9em;
   margin-bottom: 8px;
   font-weight: 500;
}

.news-title {
   font-weight: 600;
   color: #2c3e50;
   margin-bottom: 10px;
   font-size: 1.1em;
}

.news-content {
   color: #34495e;
   line-height: 1.6;
}

/* 피드백 섹션 */
.feedback-intro {
   margin-bottom: 25px;
   text-align: center;
}

.feedback-form {
   margin: 0 auto;
}

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

.form-group label {
   display: block;
   margin-bottom: 8px;
   color: #2c3e50;
   font-weight: 600;
}

.feedback-form textarea {
   width: 100%;
   min-height: 120px;
   padding: 15px;
   border: 2px solid #e9ecef;
   border-radius: 10px;
   resize: vertical;
   font-family: inherit;
   font-size: 1em;
   box-sizing: border-box;
   transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

.feedback-form textarea:focus {
   outline: none;
   border-color: #3498db;
   box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.1);
}

.form-actions {
   text-align: center;
   margin-top: 20px;
}

.feedback-button {
   background: linear-gradient(135deg, #3498db 0%, #2980b9 100%);
   color: white;
   padding: 15px 30px;
   border: none;
   border-radius: 10px;
   cursor: pointer;
   font-size: 1.1em;
   font-weight: 600;
   transition: all 0.3s ease;
   box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.feedback-button:hover {
   transform: translateY(-2px);
   box-shadow: 0 8px 15px rgba(52, 152, 219, 0.3);
}

.privacy-notice {
   text-align: center;
   margin-top: 20px;
   color: #7f8c8d;
   font-size: 0.9em;
   padding: 15px;
   background-color: #f8f9fa;
   border-radius: 8px;
}

/* 도움말 섹션 */
.help-placeholder {
   text-align: center;
   padding: 40px 20px;
   color: #95a5a6;
}

.placeholder-icon {
   font-size: 3em;
   margin-bottom: 20px;
   opacity: 0.7;
}

.help-placeholder h3 {
   font-size: 1.3em;
   margin-bottom: 10px;
   color: #7f8c8d;
}

.help-placeholder p {
   font-size: 1em;
   line-height: 1.6;
}

/* 빈 상태 */
.empty-state {
   text-align: center;
   padding: 40px 20px;
   color: #95a5a6;
}

.empty-state i {
   font-size: 3em;
   margin-bottom: 15px;
   opacity: 0.5;
}

.empty-state p {
   font-size: 1.1em;
}

/* 로딩 오버레이 */
.loading-overlay {
   position: fixed;
   top: 0;
   left: 0;
   width: 100%;
   height: 100%;
   background-color: rgba(0, 0, 0, 0.5);
   display: flex;
   justify-content: center;
   align-items: center;
   z-index: 9999;
}

.loading-content {
   background: white;
   padding: 30px;
   border-radius: 15px;
   text-align: center;
   box-shadow: 0 10px 30px rgba(0,0,0,0.3);
}

.loading-spinner {
   width: 40px;
   height: 40px;
   border: 4px solid #f3f3f3;
   border-top: 4px solid #3498db;
   border-radius: 50%;
   animation: spin 1s linear infinite;
   margin: 0 auto 15px;
}

@keyframes spin {
   0% { transform: rotate(0deg); }
   100% { transform: rotate(360deg); }
}

/* 알림 메시지 */
.alert {
   position: fixed;
   top: 20px;
   right: 20px;
   padding: 15px 20px;
   border-radius: 8px;
   color: white;
   font-weight: 600;
   z-index: 10000;
   min-width: 300px;
   display: flex;
   align-items: center;
   gap: 10px;
   box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

.alert-success {
   background: linear-gradient(135deg, #27ae60 0%, #2ecc71 100%);
}

.alert-error {
   background: linear-gradient(135deg, #e74c3c 0%, #c0392b 100%);
}

.alert-close {
   background: none;
   border: none;
   color: white;
   font-size: 18px;
   cursor: pointer;
   margin-left: auto;
   opacity: 0.8;
}

.alert-close:hover {
   opacity: 1;
}

/* 반응형 디자인 */
@media screen and (max-width: 768px) {
   .app-title {
       font-size: 2em;
   }
   
   .section {
       padding: 20px 15px;
       margin-bottom: 25px;
   }
   
   .features-grid {
       grid-template-columns: 1fr;
       gap: 20px;
   }
   
   .download-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
    /* max-width: 800px; <- 이 줄 삭제 */
    margin: 0 auto;
}

   .download-button {
       padding: 15px 20px;
   }
   
   .download-button.primary {
       padding: 18px 25px;
   }
   
   .alert {
       right: 10px;
       left: 10px;
       min-width: auto;
   }
}

@media screen and (max-width: 480px) {
   .app-title {
       font-size: 1.8em;
   }
   
   .app-subtitle {
       font-size: 1em;
   }
   
   .section {
       padding: 15px 10px;
       margin-bottom: 20px;
   }
   
   .section-title {
       font-size: 1.2em;
   }
   
   .download-button {
       flex-direction: column;
       text-align: center;
       gap: 10px;
   }
   
   .button-text {
       align-items: center;
   }
}

/* 애니메이션 효과 */
@keyframes fadeInUp {
   from {
       opacity: 0;
       transform: translateY(30px);
   }
   to {
       opacity: 1;
       transform: translateY(0);
   }
}

.section {
   animation: fadeInUp 0.6s ease-out;
}

/* 스크롤바 스타일 (웹킷 브라우저) */
::-webkit-scrollbar {
   width: 8px;
}

::-webkit-scrollbar-track {
   background: #f1f1f1;
}

::-webkit-scrollbar-thumb {
   background: #888;
   border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
   background: #555;
}