/* Google Fonts Import */
@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+KR:wght@400;700;900&display=swap');

/* --- CSS Variables --- */
:root {
    --primary-color: #2c3e50; /* Navy Blue */
    --secondary-color: #34495e; /* Darker Navy */
    --accent-color: #1abc9c;    /* Mint Green */
    --text-color: #ecf0f1;      /* Light Gray */
    --background-color: #1a2633;
    --light-background: #233446;
    --white-color: #ffffff;
    
    --font-family: 'Noto Sans KR', sans-serif;
    --header-height: 70px;
}

/* --- Global Styles & Resets --- */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-family);
    background-color: var(--background-color);
    color: var(--text-color);
    line-height: 1.6;
}

a {
    color: var(--accent-color);
    text-decoration: none;
    transition: color 0.3s ease;
}

a:hover {
    color: var(--white-color);
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 20px;
}

/* --- Header & Footer --- */
.site-header, .site-footer {
    background-color: var(--secondary-color);
    padding: 15px 0;
}

.site-header .container, .site-footer .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.site-title {
    font-weight: 900;
    font-size: 1.8rem;
    color: var(--white-color);
}

.site-nav a, .footer-nav a {
    color: var(--text-color);
    margin-left: 20px;
    font-weight: 700;
}

.site-footer {
    text-align: center;
    padding: 30px 0;
    margin-top: 40px;
    font-size: 0.9rem;
}

/* --- Homepage Specific Styles --- */
main {
    padding-top: 40px;
}

.hero-section {
    text-align: center;
    padding: 60px 20px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 10px;
}

.hero-section h2 {
    font-size: 2.8rem;
    font-weight: 900;
    margin-bottom: 15px;
}

.hero-section p {
    font-size: 1.2rem;
    max-width: 600px;
    margin: 0 auto 30px;
}

.cta-button {
    background-color: var(--accent-color);
    color: var(--white-color);
    padding: 20px 40px; /* 버튼 크기 증가 */
    border-radius: 50px;
    font-size: 1.5rem; /* 폰트 크기 증가 */
    font-weight: 700;
    transition: background-color 0.3s ease, transform 0.2s ease;
}

.cta-button:hover {
    background-color: #16a085;
    transform: translateY(-3px); /* 호버 효과 강화 */
}

.ad-section {
    margin: 40px auto;
    padding: 20px;
    background-color: var(--light-background);
    border-radius: 10px;
    text-align: center;
    min-height: 100px; /* 최소 높이 설정 */
}

.features-section {
    padding: 60px 0;
    text-align: center;
}

.features-section h3 {
    font-size: 2rem;
    margin-bottom: 40px;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.feature-item {
    background-color: var(--light-background);
    padding: 30px;
    border-radius: 10px;
    text-align: left;
}

.feature-item h4 {
    color: var(--accent-color);
    font-size: 1.3rem;
    margin-bottom: 10px;
}

/* --- About & Privacy Pages --- */
.about-page section, .privacy-page {
    background-color: var(--light-background);
    padding: 30px;
    border-radius: 10px;
    margin-bottom: 30px;
}

.about-page h2, .privacy-page h2, .privacy-page h3 {
    color: var(--accent-color);
    margin-bottom: 15px;
}

/* --- Game Page (`number-run.html`) Styles --- */
.game-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 15px;
    background-color: var(--light-background);
    padding: 30px;
    border-radius: 10px;
}

.game-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
    max-width: 400px;
}

#game-controls {
    display: flex;
    gap: 10px;
    align-items: center;
}

#difficulty-select, #start-button, #guess-button {
    padding: 10px 15px;
    border-radius: 5px;
    border: none;
    font-family: var(--font-family);
    font-size: 1rem;
}

#start-button, #guess-button {
    background-color: var(--accent-color);
    color: var(--white-color);
    cursor: pointer;
}

#start-button:disabled, #guess-button:disabled {
    background-color: #555;
    cursor: not-allowed;
}

#timer {
    font-size: 2rem;
    font-weight: 700;
}

#result-container {
    margin-top: 20px;
}

#guess-input {
    padding: 10px;
    text-align: center;
    font-size: 1.2rem;
    border: 2px solid var(--primary-color);
    background-color: var(--background-color);
    color: var(--text-color);
    border-radius: 5px;
}

#keypad {
    margin-top: 15px;
}

.game-buttons {
    position: fixed;
    bottom: 20px;
    right: 20px;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

#help-button, #ranking-button {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    border: none;
    background-color: var(--accent-color);
    color: var(--white-color);
    font-size: 1.5rem;
    cursor: pointer;
}

/* --- Modal Styles --- */
.modal-background {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.modal {
    background-color: var(--light-background);
    padding: 30px;
    border-radius: 10px;
    max-width: 500px;
    width: 90%;
    position: relative;
}

.close-modal-button {
    position: absolute;
    top: 10px;
    right: 15px;
    font-size: 1.5rem;
    background: none;
    border: none;
    color: var(--text-color);
    cursor: pointer;
}

.modal h2 {
    color: var(--accent-color);
    margin-bottom: 15px;
}

#ranking-list li {
    display: flex;
    justify-content: space-between;
    padding: 5px 0;
    border-bottom: 1px solid var(--primary-color);
}

/* --- Other --- */
.hidden {
    display: none;
}

/* -- Responsive Design -- */
@media (max-width: 768px) {
    .hero-section h2 { font-size: 2.2rem; }
    .site-header .container { flex-direction: column; gap: 10px; }
    .game-container { padding: 20px; }
}