/* --- Global Styles & Variables --- */
:root {
    --font-family-base: 'Noto Sans KR', sans-serif;
    --font-size-base: 18px;
    --font-size-lg: 22px;
    --font-size-xl: 28px;
    --font-size-display: 48px;

    --primary-color: #007BFF;
    --primary-color-dark: #0056b3;
    --text-color: #333333;
    --background-color: #FDFDFD;
    --card-background-color: #FFFFFF;
    --border-color: #E0E0E0;
    --shadow-color: rgba(0, 0, 0, 0.1);
    --glow-color: rgba(0, 123, 255, 0.5);

    --border-radius: 12px;
    --container-width: 960px;
    --header-height: 80px;
}

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

html {
    font-size: var(--font-size-base);
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family-base);
    color: var(--text-color);
    background-color: var(--background-color);
    line-height: 1.6;
    /* Subtle noise texture for a premium feel */
    background-image: linear-gradient(45deg, rgba(0,0,0,0.01) 25%, transparent 25%, transparent 75%, rgba(0,0,0,0.01) 75%, rgba(0,0,0,0.01)),
                      linear-gradient(45deg, rgba(0,0,0,0.01) 25%, transparent 25%, transparent 75%, rgba(0,0,0,0.01) 75%, rgba(0,0,0,0.01));
    background-size: 2px 2px;
    background-position: 0 0, 1px 1px;
}

/* --- Layout --- */
main#app-root {
    display: block;
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 2rem 1.5rem;
    padding-top: calc(var(--header-height) + 2rem);
    min-height: calc(100vh - var(--header-height));
}

app-header, app-footer {
    display: block;
    width: 100%;
    padding: 1rem 1.5rem;
    background-color: var(--card-background-color);
    box-shadow: 0 2px 4px var(--shadow-color);
}

app-header {
    height: var(--header-height);
    position: fixed;
    top: 0;
    left: 0;
    z-index: 1000;
}

/* --- Typography --- */
h1, h2, h3 {
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 1rem;
}

h1 { font-size: var(--font-size-xl); }
h2 { font-size: var(--font-size-lg); }
p { margin-bottom: 1rem; }

/* --- UI Components --- */
.card {
    background-color: var(--card-background-color);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    border: 1px solid var(--border-color);
    /* Multi-layered drop shadow for depth */
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.07), 0 2px 4px -2px rgba(0, 0, 0, 0.06);
    transition: box-shadow 0.3s ease;
}

.card:hover {
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.1);
}

.btn {
    display: inline-block;
    font-family: inherit;
    font-size: var(--font-size-lg);
    font-weight: 700;
    padding: 1rem 2rem;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    text-align: center;
    text-decoration: none;
    transition: all 0.3s ease;
    box-shadow: 0 2px 8px -1px var(--shadow-color);
}

.btn-primary {
    background-color: var(--primary-color);
    color: #FFFFFF;
}

.btn-primary:hover {
    background-color: var(--primary-color-dark);
    /* Glow effect */
    box-shadow: 0 0 15px var(--glow-color);
    transform: translateY(-2px);
}

/* --- Accessibility --- */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

/* --- Responsive Design --- */
@media (max-width: 768px) {
    html {
        font-size: 16px; /* Adjust base font for smaller devices */
    }

    body {
        /* Disable texture on small screens if it's distracting */
        background-image: none;
    }
    
    main#app-root {
        padding: 1rem;
        padding-top: calc(var(--header-height) + 1rem);
    }

    .btn {
        font-size: var(--font-size-base);
        padding: 0.8rem 1.5rem;
        width: 100%; /* Make buttons full-width for easier tapping */
    }
}