:root {
    --primary-color: #011d38;
    --text-color: #333;
    --subtitle-color: #585858;
    --secondary-text: #999;
    --bg-dark: #1a1a1a;
    --modal-bg: #ffffff;
    --hover-bg: #f0f0f0;
}

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

body {
    background-color: var(--bg-dark);
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    font-family: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

.modal {
    position: fixed;
    top: 48%;
    left: 50%;
    transform: translate(-50%, -50%);
    background-color: var(--modal-bg);
    padding: 30px;
    border-radius: 16px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
    z-index: 1000;
    width: 90%;
    max-width: 800px;
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding-bottom: 15px;
    border-bottom: 1px solid var(--hover-bg);
}

.logo-container {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo-title {
    color: var(--primary-color);
    font-size: 20px;
    font-weight: bold;
}

.header-controls {
    display: flex;
    align-items: center;
    gap: 8px;
}

.countdown {
    width: 30px;
    height: 30px;
    color: var(--secondary-text);
    font-size: 10px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-variant-numeric: tabular-nums;
}

.btn-icon {
    width: 36px;
    height: 36px;
    border: none;
    background: transparent;
    border-radius: 8px;
    cursor: pointer;
    display: flex;
    justify-content: center;
    align-items: center;
    color: var(--subtitle-color);
    transition: all 0.2s ease;
}

.btn-icon:hover {
    background-color: var(--hover-bg);
    color: var(--primary-color);
}

.close-btn {
    font-size: 24px;
}

.modal-content {
    color: var(--text-color);
}

sup {
    font-size: 0.6em;
    position: relative;
    top: -6px;
    left: -10px;
    vertical-align: baseline;
}

.list-icon {
    width: 20px;
    height: 20px;
    flex-shrink: 0;
}

.modal-content .guide-list {
    list-style: none;
    margin: 15px 0;
    display: grid;
    grid-template-columns: 1fr;
    gap: 0 20px;
}

.title {
    color: var(--primary-color);
    font-size: 22px;
    font-weight: bold;
    display: block;
    margin-bottom: 5px;
}

.content-subtitle {
    color: var(--subtitle-color);
    font-size: 13px;
    display: block;
    margin-bottom: 15px;
}

@media (max-width: 480px) {
    .modal-content .guide-list {
        grid-template-columns: 1fr;
    }
    .modal-content .guide-list li:nth-child(3) {
        display: none;
    }
    .desktop-only {
        display: none;
    }
}

@media (min-width: 481px) {
    .modal-content .guide-list {
        grid-template-columns: 1fr 1fr;
    }
}
.list-icon {
    width: 20px;
    height: 20px;
    flex-shrink: 0;
}

.modal-content .guide-list li {
    font-size: 15px;
    line-height: 1.5;
    padding: 8px 0;
    position: relative;
    display: flex;
    align-items: center;
    gap: 12px;
}

.modal-content .guide-list li picture {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    width: 20px;
    height: 20px;
}

.modal-content .guide-list li img {
    flex-shrink: 0;
    object-fit: contain;
}

.countdown-icon {
    width: 15px;
    height: 15px;
    flex-shrink: 0;
}

.footer-info {
    margin-top: 25px;
    padding-top: 15px;
    border-top: 1px solid var(--hover-bg);
    font-size: 13px;
    color: var(--secondary-text);
    line-height: 1.8;
}

.footer-info a {
    color: var(--primary-color);
    text-decoration: none;
    transition: opacity 0.2s;
}

.footer-info a:hover {
    text-decoration: underline;
    opacity: 0.8;
}