/* 시계 읽기 앱 - 당근 테마 스타일 */

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

body {
    font-family: 'Noto Sans KR', sans-serif;
    background: linear-gradient(135deg, #ff6b35 0%, #f7931e 50%, #ffb347 100%);
    min-height: 100vh;
    position: relative;
    overflow-x: hidden;
}

/* 당근 배경 장식 */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        radial-gradient(circle at 20% 80%, rgba(255, 255, 255, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(255, 255, 255, 0.1) 0%, transparent 50%);
    pointer-events: none;
    z-index: 0;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
    position: relative;
    z-index: 1;
    min-height: calc(100vh - 80px);
    display: flex;
    flex-direction: column;
}

/* 헤더 */
.header {
    text-align: center;
    padding: 30px 0;
    color: white;
    margin-bottom: 30px;
}

.logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    margin-bottom: 20px;
    position: relative;
}

.logo::after {
    content: '⏰🕐⏰';
    position: absolute;
    top: -15px;
    right: -60px;
    font-size: 1rem;
    opacity: 0.7;
    animation: tick 2s infinite;
}

@keyframes tick {
    0%, 100% { transform: rotate(0deg); }
    50% { transform: rotate(10deg); }
}

.logo-icon {
    font-size: 3.5rem;
    filter: drop-shadow(0 4px 8px rgba(0,0,0,0.3));
    animation: clockSpin 4s linear infinite;
}

@keyframes clockSpin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.logo-text {
    font-size: 2.5rem;
    font-weight: 700;
    text-shadow: 0 2px 4px rgba(0,0,0,0.3);
}

.subtitle {
    font-size: 1.3rem;
    opacity: 0.95;
    margin-bottom: 15px;
    text-shadow: 0 1px 3px rgba(0,0,0,0.2);
}

.description {
    font-size: 1.1rem;
    opacity: 0.9;
    max-width: 600px;
    margin: 0 auto;
    line-height: 1.6;
    text-shadow: 0 1px 2px rgba(0,0,0,0.2);
}

/* 메인 콘텐츠 */
.main-content {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px 0;
}

.menu-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 25px;
    width: 100%;
    max-width: 900px;
}

/* 메뉴 카드 */
.menu-card {
    background: rgba(255, 255, 255, 0.95);
    border-radius: 25px;
    padding: 35px 25px;
    text-align: center;
    box-shadow: 0 15px 35px rgba(255, 107, 53, 0.3);
    transition: all 0.4s ease;
    cursor: pointer;
    backdrop-filter: blur(15px);
    border: 3px solid rgba(255, 255, 255, 0.3);
    position: relative;
    overflow: hidden;
}

.menu-card::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: linear-gradient(45deg, transparent, rgba(255, 107, 53, 0.1), transparent);
    transform: rotate(45deg) translate(-100%, -100%);
    transition: transform 0.6s;
}

.menu-card:hover {
    transform: translateY(-10px) scale(1.02);
    box-shadow: 0 25px 50px rgba(255, 107, 53, 0.4);
    background: rgba(255, 255, 255, 1);
    border-color: rgba(255, 107, 53, 0.5);
}

.menu-card:hover::before {
    transform: rotate(45deg) translate(0%, 0%);
}

/* 카드별 색상 */
.learn-card .card-icon { color: #ff6b35; }
.practice-card .card-icon { color: #f7931e; }
.make-card .card-icon { color: #ff8c42; }
.game-card .card-icon { color: #ffb347; }

.card-icon {
    font-size: 4rem;
    margin-bottom: 20px;
    display: block;
    text-shadow: 0 2px 4px rgba(0,0,0,0.1);
    animation: float 3s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-10px); }
}

.card-title {
    font-size: 1.8rem;
    font-weight: 600;
    margin-bottom: 15px;
    color: #333;
}

.card-description {
    font-size: 1rem;
    color: #666;
    line-height: 1.6;
    margin-bottom: 20px;
}

.card-features {
    list-style: none;
    padding: 0;
    margin-bottom: 25px;
}

.card-features li {
    font-size: 0.9rem;
    color: #777;
    margin-bottom: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.card-features li::before {
    content: "🕐";
    font-size: 1rem;
}

.menu-btn {
    background: linear-gradient(45deg, #ff6b35, #f7931e);
    color: white;
    border: none;
    border-radius: 30px;
    padding: 15px 30px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    width: 100%;
    box-shadow: 0 8px 20px rgba(255, 107, 53, 0.3);
    position: relative;
    overflow: hidden;
}

.menu-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
    transition: left 0.5s;
}

.menu-btn:hover {
    transform: scale(1.05);
    box-shadow: 0 12px 25px rgba(255, 107, 53, 0.5);
}

.menu-btn:hover::before {
    left: 100%;
}

/* 하단 네비게이션 */
.bottom-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(15px);
    border-top: 2px solid rgba(255, 107, 53, 0.3);
    display: flex;
    justify-content: space-around;
    padding: 10px 0;
    z-index: 1000;
}

.nav-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-decoration: none;
    color: #666;
    transition: all 0.3s ease;
    padding: 5px 8px;
    border-radius: 15px;
    min-width: 50px;
    flex: 1;
}

.nav-item:hover, .nav-item.active {
    color: #ff6b35;
    background: rgba(255, 107, 53, 0.1);
    transform: translateY(-2px);
}

.nav-item i {
    font-size: 1.5rem;
    margin-bottom: 5px;
}

.nav-item span {
    font-size: 0.8rem;
    font-weight: 500;
}

/* 반응형 디자인 */
@media (max-width: 768px) {
    .container {
        padding: 15px;
        margin-bottom: 80px;
    }
    
    .header {
        padding: 20px 0;
    }
    
    .logo-text {
        font-size: 2rem;
    }
    
    .logo-icon {
        font-size: 3rem;
    }
    
    .subtitle {
        font-size: 1.1rem;
    }
    
    .description {
        font-size: 1rem;
    }
    
    .menu-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .menu-card {
        padding: 25px 20px;
    }
    
    .card-icon {
        font-size: 3rem;
    }
    
    .card-title {
        font-size: 1.5rem;
    }
    
    .logo::after {
        display: none;
    }
}

@media (max-width: 480px) {
    .logo {
        flex-direction: column;
        gap: 10px;
    }
    
    .menu-card {
        padding: 20px 15px;
    }
    
    .nav-item span {
        font-size: 0.7rem;
    }
    
    .nav-item i {
        font-size: 1.3rem;
    }
}