* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}
html {
    overflow-x: hidden;
    overflow-y: auto;
}

body {
    font-family: 'Apple SD Gothic Neo', 'Malgun Gothic', sans-serif;
    background-color: #F9F8F6;
    color: #3A3532;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    overflow-x: hidden;
    overflow-y: auto;
}
header {
    background-color: #FCFBF9;
    padding: 20px;
    font-size: 24px;
    font-weight: bold;
    text-align: center;
    border-bottom: 1px solid #DDDDDD;
    color: #3A3532;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
}
main {
    flex: 1;
    padding: 40px 20px;
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
    display: flex;
    flex-direction: column;
    gap: 30px;
}
.welcome-text {
    text-align: center;
    font-size: 22px;
    font-weight: bold;
    color: #3A3532;
}
.action-container {
    display: flex;
    justify-content: center;
}
.grid-container {
    display: grid;
    grid-template-columns: 1fr;
    gap: 20px;
}
@media (min-width: 600px) {
    .grid-container {
        grid-template-columns: repeat(2, 1fr);
    }
}
@media (min-width: 1024px) {
    .grid-container {
        grid-template-columns: repeat(4, 1fr);
    }
}

.card {
    background-color: rgba(252, 251, 249, 0.75); /* 기존 배경색 #FCFBF9에 75% 불투명도 적용 */
    backdrop-filter: blur(6px); /* 카드 뒤로 지나가는 파티클을 살짝 흐리게 처리하여 글자 가독성 확보 */
    -webkit-backdrop-filter: blur(6px); /* 사파리 브라우저 호환성 */
    border-radius: 16px;
    padding: 40px 20px;
    text-align: center;
    text-decoration: none;
    border: 1px solid rgba(221, 221, 221, 0.8); /* 테두리도 살짝 투명하게 */
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    min-height: 220px;
    color: #3A3532;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.05);
}

.card h2 {
    font-size: 20px;
    margin-bottom: 12px;
    color: #3A3532;
}

.card p {
    font-size: 15px;
    color: #6B6B6B;
    word-break: keep-all;
}

.card-ad {
    background-color: #F9F8F6;
    background-image: none;
    border: 2px dashed #DDDDDD;
    color: #6B6B6B;
    box-shadow: none;
    cursor: default;
}

.card-ad h2 {
    color: #6B6B6B;
}

.card-ad p {
    color: #6B6B6B;
}

.card-btn {
    margin-top: 20px;
    padding: 12px 0;
    width: 80%;
    background-color: #E8EAED;
    color: #3A3532;
    text-decoration: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: bold;
    display: flex;
    justify-content: center;
    align-items: center;
    border: 1px solid #D1D5DB;
    cursor: pointer;
    font-family: inherit;
    white-space: nowrap;
    word-break: keep-all;
    transition: background-color 0.2s;
    -webkit-appearance: none;
    appearance: none;
}

.card-btn:hover {
    background-color: #D1D5DB;
}

.intro-body {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    background-color: #F9F8F6;
    margin: 0;
}

.intro-container {
    text-align: center;
    background-color: #FCFBF9;
    padding: 60px 40px;
    border-radius: 16px;
    box-shadow: 0 4px 12px rgba(47, 50, 54, 0.05);
    border: 1px solid #DDDDDD;
    max-width: 400px;
    width: 90%;
}

.intro-title {
    font-size: 48px;
    color: #3A3532;
    margin-bottom: 20px;
    font-weight: bold;
}

.intro-desc {
    font-size: 18px;
    color: #6B6B6B;
    margin-bottom: 40px;
    line-height: 1.6;
    word-break: keep-all;
}

.intro-btn {
    background-color: #3A3532;
    color: #FCFBF9;
    border: none;
    padding: 16px 40px;
    font-size: 20px;
    font-weight: bold;
    border-radius: 30px;
    cursor: pointer;
}

.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(47, 50, 54, 0.6);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 20;
}

.modal.hidden {
    display: none !important;
}

.modal-content {
    background-color: #FCFBF9;
    padding: 30px;
    border-radius: 16px;
    text-align: center;
    border: 1px solid #DDDDDD;
    width: 80%;
    max-width: 400px;
}

.modal-content h3 {
    color: #3A3532;
    margin-bottom: 20px;
}

.modal-btn-group {
    display: flex;
    gap: 10px;
    justify-content: center;
    margin-top: 15px;
}

.sys-btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    white-space: nowrap;
    flex-shrink: 0;
    word-break: keep-all;
}

.btn-exit {
    background-color: #FCFBF9;
    color: #3A3532;
    border: 1px solid #DDDDDD;
}

.settings-btn {
    background: none;
    border: none;
    color: #3A3532;
    font-size: 20px;
    cursor: pointer;
}
.particle-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    z-index: -10;
    pointer-events: none;
}

.particle {
    position: absolute;
    background-color: #3A3532;
    border-radius: 50%;
    animation: moveParticle linear infinite;
}

@keyframes moveParticle {
    0% {
        transform: translateY(-10vh) scale(1);
    }
    100% {
        transform: translateY(110vh) scale(0.5);
    }
}