@import url("https://fonts.googleapis.com/css2?family=Noto+Sans+KR:wght@300;400;500;700&display=swap");

:root {
  --primary-color: #4db6ac;
  --secondary-color: #00acc1;
  --bg-color: #f0f2f5;
  --card-bg: #ffffff;
  --text-main: #333;
  --text-sub: #666;
  --nav-bg: #ffffff;
  --footer-bg: #333;
  --footer-text: #ccc;
  --footer-link: #aaa;
  --shadow: 0 8px 25px rgba(0,0,0,0.04);
  --border-radius: 20px;
  --font-family: 'Noto Sans KR', sans-serif;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

body.dark-mode {
  --bg-color: #121212;
  --card-bg: #1e1e1e;
  --text-main: #e0e0e0;
  --text-sub: #a0a0a0;
  --nav-bg: #1a1a1a;
  --footer-bg: #0a0a0a;
  --footer-text: #888;
  --footer-link: #666;
  --shadow: 0 8px 25px rgba(0,0,0,0.2);
}

* { box-sizing: border-box; }

body {
  font-family: var(--font-family);
  background-color: var(--bg-color);
  color: var(--text-main);
  margin: 0;
  padding: 0;
  line-height: 1.6;
  transition: background-color 0.3s, color 0.3s;
  overflow-x: hidden;
}

/* Page Transitions */
.page-transition {
  animation: fadeIn 0.5s ease-out;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Common Layout Components */
nav {
  background: var(--nav-bg);
  padding: 1rem 2rem;
  box-shadow: 0 2px 10px rgba(0,0,0,0.05);
  position: sticky;
  top: 0;
  z-index: 100;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: background-color 0.3s;
}

nav .logo {
  font-weight: 700;
  font-size: 1.2rem;
  color: var(--primary-color);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.back-btn, .icon-btn {
  text-decoration: none;
  font-size: 1.2rem;
  color: var(--text-sub);
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  transition: var(--transition);
  background: none;
  border: none;
  cursor: pointer;
}

.back-btn:hover, .icon-btn:hover {
  background: rgba(0,0,0,0.05);
  color: var(--primary-color);
}

body.dark-mode .back-btn:hover, body.dark-mode .icon-btn:hover {
  background: rgba(255,255,255,0.05);
}

nav .nav-links {
  display: flex;
  align-items: center;
}

nav .nav-links a {
  margin-left: 1.5rem;
  text-decoration: none;
  color: var(--text-sub);
  font-size: 0.9rem;
  font-weight: 500;
  transition: color 0.2s;
}

nav .nav-links a:hover { color: var(--primary-color); }

/* Dark Mode Toggle Button */
.theme-toggle {
  background: none;
  border: none;
  cursor: pointer;
  font-size: 1.2rem;
  padding: 0.5rem;
  margin-left: 1rem;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background-color 0.2s;
  color: var(--text-main);
}

.theme-toggle:hover {
  background-color: rgba(0,0,0,0.05);
}

body.dark-mode .theme-toggle:hover {
  background-color: rgba(255,255,255,0.1);
}

/* Footer Styles */
footer {
  background: var(--footer-bg);
  color: var(--footer-text);
  padding: 4rem 2rem;
  text-align: center;
  margin-top: 6rem;
  transition: background-color 0.3s;
}

.footer-content {
  max-width: 1100px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 2rem;
  text-align: left;
  padding-bottom: 2rem;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}

footer a { color: var(--footer-link); text-decoration: none; transition: color 0.2s; }
footer a:hover { color: var(--primary-color); }

/* Common Input Styles */
input, textarea, select {
  background: var(--card-bg);
  color: var(--text-main);
  border: 1px solid rgba(0,0,0,0.1);
  transition: var(--transition);
}

body.dark-mode input, 
body.dark-mode textarea, 
body.dark-mode select {
  border-color: rgba(255,255,255,0.1);
}

input:focus, textarea:focus {
  outline: none;
  border-color: var(--primary-color) !important;
  box-shadow: 0 0 0 3px rgba(77, 182, 172, 0.2);
}

/* Mobile Bottom Nav */
.mobile-nav {
  display: none;
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background: var(--nav-bg);
  box-shadow: 0 -2px 10px rgba(0,0,0,0.05);
  z-index: 1000;
  padding: 0.5rem 0;
  justify-content: space-around;
  border-top: 1px solid rgba(0,0,0,0.05);
}

.mobile-nav-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-decoration: none;
  color: var(--text-sub);
  font-size: 0.7rem;
  gap: 0.2rem;
}

.mobile-nav-item.active {
  color: var(--primary-color);
}

.mobile-nav-item i {
  font-size: 1.2rem;
}

@media (max-width: 768px) {
  nav .nav-links { display: none; }
  .mobile-nav { display: flex; }
  body { padding-bottom: 60px; }
}

/* Global Card & Container */
.container {
  width: 100%;
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

header {
  text-align: center;
  padding: 3rem 0;
  width: 100%;
}

h1 {
  text-align: center;
}

header h1 {
  margin-bottom: 1rem;
  text-align: center;
}

.card {
  background: var(--card-bg);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow);
  transition: var(--transition);
}

.card .icon {
  transition: transform 0.3s ease;
  background: rgba(77, 182, 172, 0.05) !important;
  box-shadow: inset 0 0 0 1px rgba(77, 182, 172, 0.1);
}

.card:hover .icon {
  transform: scale(1.1) rotate(5deg);
  background: rgba(77, 182, 172, 0.1) !important;
}