:root {
  /* Colors - Light Mode (Default) */
  --bg-color: #f7f8fa;
  --text-color: #333333;
  --surface-color: #ffffff;
  --border-color: #eeeeee;
  
  --primary-color: #ffc1cc;
  --primary-hover: #ffb7c5; 
  --on-primary: #333333;

  --accent-color: #555555;
  --completed-bar-bg: #ffe0e6;
  
  /* Spacing */
  --spacing-sm: 8px;
  --spacing-md: 16px;
  --spacing-lg: 24px;
  
  /* Typography */
  --font-family: 'Gowun Dodum', 'Pretendard', sans-serif;
  --font-size-base: 16px;
  --font-size-lg: 20px;
  --font-size-xl: 24px;
  --icon-filter: none;
}

[data-theme="dark"] {
  --bg-color: #121212;
  --text-color: #e0e0e0;
  --surface-color: #1e1e1e;
  --border-color: #333333;
  
  --primary-color: #f48fb1; 
  --primary-hover: #f06292;
  --on-primary: #121212;

  --accent-color: #ffffff;
  --completed-bar-bg: #4a2a32;
  --icon-filter: invert(1);
}

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

html {
  scrollbar-gutter: stable;
}

body {
  font-family: var(--font-family);
  background-color: var(--bg-color);
  color: var(--text-color);
  transition: background-color 0.3s ease, color 0.3s ease;
  line-height: 1.5;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  overflow-y: scroll; /* Force vertical scrollbar to avoid jumping */
}

/* Layout Utilities */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--spacing-md);
  width: 100%;
  flex-grow: 1;
  display: flex;
  flex-direction: column;
}

@media (max-width: 600px) {
  .container {
    padding: var(--spacing-sm);
  }
}

/* Ensure app view takes full height */
#app-view {
    display: block;
    min-height: 100vh;
}

button {
  cursor: pointer;
  border: none;
  font-family: inherit;
  transition: all 0.2s;
  -webkit-tap-highlight-color: transparent;
}

button:hover {
  opacity: 0.8;
}

button:active {
    transform: scale(0.98);
}

input, textarea {
  font-family: inherit;
  border: 1px solid var(--border-color);
  background: var(--surface-color);
  color: var(--text-color);
  padding: var(--spacing-sm);
  border-radius: 8px;
  font-size: 16px; /* Prevent iOS auto-zoom */
}

input:focus, textarea:focus {
  outline: 2px solid var(--primary-color);
}

/* Specific Component Styles (Global for simplicity or shared) */
.card {
  background-color: var(--surface-color);
  border-radius: 12px;
  padding: var(--spacing-md);
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
  margin-bottom: var(--spacing-md);
}

/* Split Layout */
#main-content {
  display: grid;
  grid-template-columns: 1.8fr 1fr;
  gap: var(--spacing-lg);
  align-items: start;
}

@media (max-width: 1024px) {
  #main-content {
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
  }
}

@media (max-width: 600px) {
    #main-content {
        gap: 10px;
    }
}

h1, h2, h3 {
  font-weight: 700;
  margin-bottom: var(--spacing-sm);
}

.btn-primary {
  background-color: var(--primary-color);
  color: var(--on-primary);
  padding: 8px 16px;
  border-radius: 20px;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.btn-icon {
  background: transparent;
  color: var(--text-color);
  padding: 8px;
  border-radius: 50%;
  font-size: 1.2rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

.hidden {
  display: none !important;
}

/* Custom Checkbox */
input[type="checkbox"] {
  appearance: none;
  -webkit-appearance: none;
  width: 20px;
  height: 20px;
  border: 2px solid var(--primary-color);
  border-radius: 6px;
  cursor: pointer;
  position: relative;
  transition: background 0.2s, border-color 0.2s;
  flex-shrink: 0;
}

input[type="checkbox"]:checked {
  background-color: var(--primary-color);
  border-color: var(--primary-color);
}

input[type="checkbox"]:checked::after {
  content: '✔';
  font-size: 14px;
  color: white;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-weight: bold;
}

input[type="checkbox"]:hover {
  background-color: rgba(255, 193, 204, 0.2);
}

/* Login View */
app-login {
  display: block; /* Changed from flex to block for scrolling content */
  min-height: 100vh;
  background-color: var(--bg-color);
}

/* My Page */
.my-page-container {
    background: var(--surface-color);
    padding: 20px;
    border-radius: 12px;
    margin-bottom: 20px;
}

.profile-section {
    display: flex;
    align-items: center;
    gap: 15px;
    margin-bottom: 20px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--border-color);
}

.friend-search {
    display: flex;
    gap: 10px;
    margin-bottom: 15px;
}

.friend-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 10px;
}

.friend-card {
    background: var(--bg-color);
    padding: 10px;
    border-radius: 8px;
    text-align: center;
    border: 1px solid var(--border-color);
}

.friend-card.mutual {
    border-color: var(--primary-color);
    background-color: rgba(255, 193, 204, 0.1);
}

.badge {
    display: inline-block;
    padding: 2px 8px;
    border-radius: 10px;
    font-size: 0.7rem;
    background: var(--primary-color);
    color: white;
}

@keyframes pulse {
  0% { transform: scale(1); opacity: 1; }
  50% { transform: scale(1.1); opacity: 0.8; }
  100% { transform: scale(1); opacity: 1; }
}