@import url('https://cdn.jsdelivr.net/gh/orioncactus/pretendard/dist/web/static/pretendard.css');

:root {
    --primary-color: #007BFF;
    --primary-dark-color: #0056b3;
    --primary-light-color: #e6f2ff;
    --secondary-color: #17a2b8;
    --secondary-dark-color: #117a8b;
    --background-color: #f4f6f9;
    --surface-color: #ffffff;
    --text-color: #212529;
    --muted-text-color: #6c757d;
    --border-color: #dee2e6;
    --shadow-sm: 0 4px 8px rgba(0, 0, 0, 0.04);
    --shadow-md: 0 8px 16px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 15px 30px rgba(0, 0, 0, 0.1);
    --border-radius: 20px;
}

/* --- Dark Mode Color Palette --- */
:root.dark-mode {
    --background-color: #121212;
    --surface-color: #1e1e1e;
    --text-color: #e0e0e0;
    --muted-text-color: #888888;
    --border-color: #333333;
    --primary-light-color: #2a3a4b;
    --shadow-sm: 0 4px 8px rgba(0, 0, 0, 0.2);
    --shadow-md: 0 8px 16px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 15px 30px rgba(0, 0, 0, 0.4);
}

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

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

body {
    font-family: 'Pretendard', sans-serif;
    background: var(--background-color);
    padding: 50px 20px;
    min-height: 100%;
    transition: background-color 0.3s;
}

#app {
    width: 100%;
    max-width: 800px;
    margin: 0 auto;
    background-color: var(--surface-color);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border-color);
    padding: 50px;
    transition: max-width 0.5s ease-in-out, background-color 0.3s, border-color 0.3s;
    position: relative;
    overflow: hidden;
}

#input-view, #results-view {
    width: 100%;
    display: flex;
    flex-direction: column;
}

#results-view { display: none; }
#app.show-results { max-width: 1100px; }
#app.show-results #input-view { display: none; }
#app.show-results #results-view { display: flex; animation: fadeIn 0.4s ease-out; }

/* --- Header & Theme Toggle --- */
header { text-align: center; margin-bottom: 40px; }
.header-content { display: flex; justify-content: center; align-items: center; gap: 20px; margin-bottom: 10px; }
header h1 {
    background: linear-gradient(45deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    font-size: 3.5rem;
    font-weight: 800;
}
#theme-toggle-btn {
    background-color: var(--primary-light-color);
    border: 1px solid var(--border-color);
    border-radius: 50%;
    width: 44px;
    height: 44px;
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    transition: all 0.3s ease;
}
#theme-toggle-btn .material-icons {
    color: var(--text-color);
    font-size: 24px;
}
#theme-toggle-btn:hover {
    transform: translateY(-2px) rotate(15deg);
    box-shadow: var(--shadow-md);
}

/* --- Rest of the styles --- */
#add-location-btn, #find-midpoint-btn, #back-to-input-btn {
    background-color: var(--surface-color); /* To ensure proper dark mode bg */
    border-color: var(--border-color);
}

#add-location-btn {
    width: 100%; padding: 15px; font-size: 1.1rem; font-weight: 600; color: var(--secondary-dark-color);
    background-color: #f1fafa; border: 2px dashed #d0e8ec; border-radius: var(--border-radius);
    cursor: pointer; margin-top: 20px; box-shadow: var(--shadow-sm); transition: all 0.3s ease;
    display: flex; align-items: center; justify-content: center; gap: 10px;
}
:root.dark-mode #add-location-btn { background-color: #2a3b4c; border-color: #3a5c7d; color: #a2c9e8; }

#add-location-btn:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); border-color: var(--secondary-color); }
#find-midpoint-btn {
    width: 100%; padding: 20px; font-size: 1.3rem; font-weight: 700; color: white;
    background: linear-gradient(45deg, var(--primary-color), var(--primary-dark-color));
    border: none; border-radius: var(--border-radius); cursor: pointer; margin-top: 30px;
    box-shadow: 0 6px 15px rgba(0, 123, 255, 0.4); transition: transform 0.2s, box-shadow 0.2s, background 0.3s ease;
}
#find-midpoint-btn:hover {
    transform: translateY(-3px); box-shadow: 0 10px 25px rgba(0, 123, 255, 0.5);
    background: linear-gradient(45deg, var(--primary-dark-color), var(--primary-color));
}

.results-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 20px; }
.results-header h2 { font-size: 2rem; color: var(--text-color); margin: 0; }
#back-to-input-btn {
    display: flex; align-items: center; gap: 8px; background: none;
    border: 1px solid var(--border-color); border-radius: var(--border-radius);
    padding: 10px 20px; font-size: 1rem; cursor: pointer; transition: all 0.2s; color: var(--text-color);
}
#back-to-input-btn:hover { background-color: var(--primary-light-color); border-color: var(--primary-color); }

.map-warning { background-color: #fff3cd; padding: 15px; margin-bottom: 20px; display: flex; align-items: center; gap: 10px; font-size: 1rem; border-radius: var(--border-radius); }
:root.dark-mode .map-warning { background-color: #332b00; color: #ffeb85; border: 1px solid #665b1f; }
:root.dark-mode .leaflet-tile { filter: brightness(0.6) invert(1) contrast(3) hue-rotate(200deg) saturate(0.3) brightness(0.7); }

#map { width: 100%; height: 500px; border-radius: var(--border-radius); box-shadow: var(--shadow-sm); margin-bottom: 20px; background-color: #aaa; }
#midpoint-result { font-size: 1.2rem; font-weight: 600; padding: 20px; background-color: var(--primary-light-color); border-left: 5px solid var(--primary-color); text-align: center; margin-bottom: 20px; }
#details-result { display: grid; grid-template-columns: 1fr 1fr; gap: 15px; }
#details-result .detail-item { background-color: var(--surface-color); border: 1px solid var(--border-color); border-radius: var(--border-radius); padding: 15px; box-shadow: var(--shadow-sm); transition: transform 0.2s, box-shadow 0.2s, background-color 0.3s, border-color 0.3s; }
#details-result .detail-item:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); }
#details-result .detail-item p { margin: 0; }
#details-result .detail-item .address { font-weight: 600; margin-bottom: 8px;}
#details-result .detail-item .info { color: var(--muted-text-color); display: flex; align-items: center; gap: 8px;}