/* ===== 기본 스타일 및 변수 ===== */
:root {
  /* 컬러 시스템 */
  --primary-color: #2563eb;
  --primary-hover: #1d4ed8;
  --secondary-color: #64748b;
  --success-color: #16a34a;
  --warning-color: #ea580c;
  --error-color: #dc2626;
  
  /* 배경색 */
  --bg-primary: #ffffff;
  --bg-secondary: #f8fafc;
  --bg-tertiary: #e2e8f0;
  
  /* 텍스트 색상 */
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #64748b;
  --text-inverse: #ffffff;
  
  /* 테두리 */
  --border-color: #e2e8f0;
  --border-hover: #cbd5e1;
  
  /* 그림자 */
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  
  /* 타이포그래피 */
  --font-family: 'Noto Sans KR', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;
  
  /* 간격 */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  
  /* 반지름 */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  
  /* 애니메이션 */
  --transition-fast: 0.15s ease-in-out;
  --transition-normal: 0.3s ease-in-out;
  --transition-slow: 0.5s ease-in-out;
}



/* ===== 기본 리셋 ===== */
*, *::before, *::after {
  box-sizing: border-box;
}

* {
  margin: 0;
}

html {
  height: 100%;
  scroll-behavior: smooth;
  font-size: 16px; /* 기본 폰트 크기 명시적 설정 */
}

body {
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  transition: background-color var(--transition-normal), color var(--transition-normal);
}

img, picture, video, canvas, svg {
  display: block;
  max-width: 100%;
}

input, button, textarea, select {
  font: inherit;
}

p, h1, h2, h3, h4, h5, h6 {
  overflow-wrap: break-word;
}

/* ===== 접근성 ===== */
.skip-link {
  position: absolute;
  top: -40px;
  left: 6px;
  background: var(--primary-color);
  color: var(--text-inverse);
  padding: 8px;
  text-decoration: none;
  border-radius: var(--radius-sm);
  z-index: 1000;
  transition: top var(--transition-fast);
}

.skip-link:focus {
  top: 6px;
}

/* ===== 레이아웃 ===== */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

@media (min-width: 768px) {
  .container {
    padding: 0 var(--spacing-lg);
  }
}

/* ===== 헤더 ===== */
.header {
  background-color: var(--bg-primary);
  border-bottom: 1px solid var(--border-color);
  padding: var(--spacing-lg) 0;
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  min-height: 80px;
  display: flex;
  align-items: center;
}

.header .container {
  width: 100%;
  max-width: var(--container-max-width, 1200px);
  margin: 0 auto;
  padding: 0 var(--container-padding, 1rem);
}

/* ===== 헤더 통일 스타일 ===== */
.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--spacing-lg);
  width: 100%;
  min-height: 48px;
}

.header-left {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  flex-shrink: 0;
}

.header-title {
  font-size: var(--font-size-base);
  font-weight: 700;
  margin: 0;
  line-height: 1.2;
}

.header-link {
  color: var(--text-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
  display: block;
}

.header-link:hover {
  color: var(--primary-color);
}

.header-subtitle {
  background: var(--primary-color);
  color: white;
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
  font-size: var(--font-size-base);
  font-weight: 600;
  white-space: nowrap;
  flex-shrink: 0;
}

.header-nav {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  flex-shrink: 0;
  height: 48px;
}

.nav-link {
  color: var(--text-secondary);
  text-decoration: none;
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
  font-weight: 500;
  font-size: var(--font-size-base);
  line-height: 1;
  white-space: nowrap;
  display: flex;
  align-items: center;
  min-height: 36px;
}

.nav-link:hover {
  color: var(--primary-color);
  background-color: var(--bg-secondary);
}

.nav-link.active {
  color: var(--primary-color);
  background-color: var(--bg-secondary);
  font-weight: 600;
}



/* ===== 메인 콘텐츠 ===== */
.main {
  flex: 1;
  padding: var(--spacing-xl) 0;
}

.intro {
  text-align: center;
  margin-bottom: var(--spacing-2xl);
}

.intro-title {
  font-size: var(--font-size-3xl);
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: var(--spacing-md);
}

.intro-description {
  font-size: var(--font-size-lg);
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

/* ===== 디바이스 안내 ===== */
.device-notice {
  background: linear-gradient(135deg, #fef3c7, #fed7aa);
  border: 1px solid #f59e0b;
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  margin-bottom: var(--spacing-xl);
  display: none;
}

.device-notice.desktop-only {
  display: block;
}

@media (max-width: 768px) {
  .device-notice.desktop-only {
    display: none;
  }

  /* ===== 모바일 헤더 완전 통일 ===== */
  .header {
    padding: var(--spacing-md) 0;
    min-height: 80px;
  }

  .header-content {
    flex-direction: column !important;
    justify-content: center !important;
    align-items: center !important;
    gap: var(--spacing-sm) !important;
    min-height: 48px;
  }

  .header-left {
    width: 100% !important;
    display: flex !important;
    flex-direction: column !important;
    align-items: center !important;
    gap: 4px !important;
    text-align: center !important;
  }

  .header-title {
    font-size: var(--font-size-base) !important;
    line-height: 1.2 !important;
    white-space: nowrap !important;
    order: 1 !important;
  }

  .header-subtitle {
    font-size: var(--font-size-sm) !important;
    padding: 4px 12px !important;
    white-space: nowrap !important;
    order: 2 !important;
  }

  .header-nav {
    width: 100% !important;
    display: flex !important;
    justify-content: center !important;
    flex-wrap: nowrap !important;
    gap: var(--spacing-sm) !important;
    height: auto !important;
    order: 3 !important;
  }

  .nav-link {
    padding: var(--spacing-xs) var(--spacing-md) !important;
    font-size: var(--font-size-sm) !important;
    min-height: 36px !important;
    white-space: nowrap !important;
    flex-shrink: 0 !important;
    border-radius: var(--radius-sm) !important;
  }


}

.notice-content {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
}

.notice-icon {
  font-size: var(--font-size-2xl);
  flex-shrink: 0;
}

.notice-text h3 {
  color: #92400e;
  margin-bottom: var(--spacing-xs);
  font-size: var(--font-size-lg);
  font-weight: 600;
}

.notice-text p {
  color: #a16207;
  font-size: var(--font-size-base);
}

/* ===== 사용 방법 안내 ===== */
.usage-guide {
  background-color: var(--bg-secondary);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  margin-top: var(--spacing-2xl);
}

.usage-guide h3 {
  font-size: var(--font-size-xl);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--spacing-lg);
  text-align: center;
}

.usage-steps {
  list-style: none;
  padding: 0;
  display: grid;
  gap: var(--spacing-md);
}

.usage-steps li {
  background-color: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: var(--spacing-lg);
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  position: relative;
  counter-increment: step-counter;
}

.usage-steps li::before {
  content: counter(step-counter);
  background-color: var(--primary-color);
  color: var(--text-inverse);
  width: 2rem;
  height: 2rem;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: var(--font-size-sm);
  flex-shrink: 0;
}

.usage-steps {
  counter-reset: step-counter;
}

/* ===== 푸터 ===== */
.footer {
  background-color: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  padding: var(--spacing-xl) 0;
  text-align: center;
}

.footer-text {
  color: var(--text-secondary);
  font-size: var(--font-size-sm);
  margin-bottom: var(--spacing-sm);
}

.footer-text a {
  color: var(--primary-color);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.footer-text a:hover {
  color: var(--primary-hover);
  text-decoration: underline;
}

.footer-notice {
  color: var(--text-muted);
  font-size: var(--font-size-sm);
}

.footer-sources {
  color: var(--text-secondary);
  font-size: var(--font-size-sm);
  line-height: 1.6;
  margin: var(--spacing-md) 0;
  padding: var(--spacing-md);
  background-color: var(--bg-tertiary);
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
}

.footer-sources strong {
  color: var(--text-primary);
}

.footer-sources small {
  color: var(--text-muted);
  font-style: italic;
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: var(--spacing-lg);
  margin: var(--spacing-md) 0;
  flex-wrap: wrap;
}

.footer-link {
  color: var(--primary-color);
  text-decoration: none;
  font-size: var(--font-size-sm);
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
}

.footer-link:hover {
  color: var(--primary-hover);
  background-color: var(--bg-tertiary);
  text-decoration: underline;
}

/* ===== 로딩 인디케이터 ===== */
.loading {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(0, 0, 0, 0.5);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  z-index: 9999;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-normal);
}

.loading.active {
  opacity: 1;
  visibility: visible;
}

.loading-spinner {
  width: 3rem;
  height: 3rem;
  border: 3px solid var(--bg-tertiary);
  border-top: 3px solid var(--primary-color);
  border-radius: 50%;
  animation: spin 1s linear infinite;
  margin-bottom: var(--spacing-md);
}

.loading p {
  color: var(--text-inverse);
  font-size: var(--font-size-lg);
}

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

/* ===== 반응형 디자인 ===== */
@media (max-width: 480px) {
  .container {
    padding: 0 var(--spacing-sm);
  }
  
  .intro-title {
    font-size: var(--font-size-2xl);
  }
  
  .intro-description {
    font-size: var(--font-size-base);
  }
  
  .usage-guide {
    padding: var(--spacing-lg);
  }
  
  .usage-steps li {
    flex-direction: column;
    text-align: center;
    gap: var(--spacing-sm);
  }
  
  .notice-content {
    flex-direction: column;
    text-align: center;
  }
}

/* ===== 포커스 관리 ===== */
:focus-visible {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}



@media (max-width: 480px) {
  .ad-placeholder {
    padding: var(--spacing-sm);
    min-height: 80px;
  }
  
  .ad-text {
    font-size: var(--font-size-sm);
  }
}

/* ===== 인쇄 스타일 ===== */
@media print {
  .header, .footer, .theme-toggle, .device-notice {
    display: none;
  }
  
  body {
    background: white;
    color: black;
  }
} 

/* ===== 헤더 반응형 ===== */
@media (max-width: 768px) {
  .header-content {
    flex-direction: column;
    gap: var(--spacing-md);
    text-align: center;
  }
  
  .header-left {
    flex-direction: column;
    gap: var(--spacing-sm);
  }
  
  .header-title {
    font-size: var(--font-size-lg);
  }
  
  .header-nav {
    gap: var(--spacing-sm);
  }
  
  .nav-link {
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: var(--font-size-xs);
  }
}

@media (max-width: 480px) {
  .header-left {
    gap: var(--spacing-xs);
  }
  
  .header-title {
    font-size: var(--font-size-base);
  }
  
  .header-subtitle {
    font-size: var(--font-size-xs);
    padding: 2px var(--spacing-xs);
  }
  
  .header-nav {
    flex-wrap: wrap;
    justify-content: center;
  }
} 

/* ========================================
   문자 예시 UI 스타일
======================================== */

.message-preview {
  margin: 2rem 0;
  padding: 0 1rem;
}

.preview-container {
  max-width: 600px;
  margin: 0 auto;
}

.preview-title {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-primary);
  text-align: center;
  margin-bottom: 1rem;
}

.preview-card {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border-radius: 16px;
  overflow: hidden;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.preview-header {
  background: rgba(255, 255, 255, 0.1);
  padding: 0.75rem 1rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
}

.preview-label {
  color: white;
  font-weight: 500;
  font-size: 0.9rem;
}

.preview-time {
  color: rgba(255, 255, 255, 0.8);
  font-size: 0.8rem;
  padding: 0.25rem 0.5rem;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 12px;
}

.preview-content {
  padding: 1.5rem;
  background: rgba(255, 255, 255, 0.95);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
}

.message-example {
  font-family: var(--font-family);
  font-size: 0.95rem;
  line-height: 1.6;
  color: var(--text-primary);
  word-break: keep-all;
}

.message-example span {
  display: inline;
}

.date-part {
  color: #2563eb;
  font-weight: 600;
}

.line-part {
  color: #dc2626;
  font-weight: 700;
  margin: 0 0.25rem;
}

.editable-part {
  background: #fef3c7;
  color: #92400e;
  padding: 0.1rem 0.3rem;
  border-radius: 4px;
  font-weight: 500;
  margin: 0 0.15rem;
  border: 1px solid #fbbf24;
}

.content-part {
  color: var(--text-primary);
  margin-left: 0.25rem;
}

.preview-footer {
  background: rgba(255, 255, 255, 0.1);
  padding: 1rem;
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
}

.edit-notice {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: white;
  font-size: 0.85rem;
}

.edit-icon {
  font-size: 1rem;
}

.edit-notice strong {
  color: #fbbf24;
  font-weight: 600;
}

/* 다크 모드 */
[data-theme="dark"] .preview-card {
  background: linear-gradient(135deg, #1e3a8a 0%, #3730a3 100%);
}

[data-theme="dark"] .preview-content {
  background: rgba(15, 23, 42, 0.95);
}

[data-theme="dark"] .message-example {
  color: var(--text-primary);
}

[data-theme="dark"] .editable-part {
  background: #451a03;
  color: #fbbf24;
  border-color: #92400e;
}

/* 반응형 디자인 */
@media (max-width: 480px) {
  .message-preview {
    margin: 1.5rem 0;
    padding: 0 0.5rem;
  }
  
  .preview-title {
    font-size: 1.1rem;
  }
  
  .preview-card {
    border-radius: 12px;
  }
  
  .preview-content {
    padding: 1rem;
  }
  
  .message-example {
    font-size: 0.9rem;
  }
  
  .edit-notice {
    font-size: 0.8rem;
  }
}

/* ========================================