/* iPhone 16 外观样式 */
.iphone-container {
    width: 375px;
    height: 812px;
    background: linear-gradient(145deg, #1a1a1a, #2d2d2d);
    border-radius: 45px;
    padding: 8px;
    box-shadow: 0 25px 50px rgba(0, 0, 0, 0.3);
    position: relative;
}

.iphone-container::before {
    content: '';
    position: absolute;
    top: 30px;
    left: 50%;
    transform: translateX(-50%);
    width: 120px;
    height: 30px;
    background: #1a1a1a;
    border-radius: 15px;
    z-index: 10;
}

.screen-content {
    width: 100%;
    height: 100%;
    background: white;
    border-radius: 38px;
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.status-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 20px 8px;
    font-size: 14px;
    font-weight: 600;
    background: white;
    z-index: 5;
}

.bottom-nav {
    display: flex;
    justify-content: space-around;
    align-items: center;
    background: white;
    border-top: 1px solid #e5e7eb;
    padding: 8px 0 20px;
    box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.1);
}

.nav-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 8px 12px;
    color: #9ca3af;
    transition: all 0.3s ease;
    border-radius: 12px;
}

.nav-item.active {
    color: #3b82f6;
    background: #dbeafe;
}

.nav-item:hover {
    color: #3b82f6;
    transform: translateY(-2px);
}

/* 学习卡片样式 */
.word-card {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 20px;
    padding: 30px;
    color: white;
    text-align: center;
    box-shadow: 0 10px 30px rgba(102, 126, 234, 0.3);
    transform: perspective(1000px) rotateY(0deg);
    transition: transform 0.6s;
}

.word-card.flipped {
    transform: perspective(1000px) rotateY(180deg);
}

/* 游戏按钮样式 */
.game-btn {
    background: linear-gradient(135deg, #ff7b7b, #ff9a9e);
    border-radius: 16px;
    padding: 20px;
    text-align: center;
    color: white;
    transition: all 0.3s ease;
    box-shadow: 0 8px 25px rgba(255, 123, 123, 0.3);
}

.game-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 35px rgba(255, 123, 123, 0.4);
}

/* 进度条样式 */
.progress-ring {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    background: conic-gradient(#3b82f6 0deg 216deg, #e5e7eb 216deg 360deg);
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}

.progress-ring::before {
    content: '';
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background: white;
    position: absolute;
}

.progress-text {
    position: relative;
    z-index: 1;
    font-weight: bold;
    color: #3b82f6;
}

/* 成就徽章样式 */
.achievement-badge {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background: linear-gradient(135deg, #ffd700, #ffed4e);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    box-shadow: 0 8px 25px rgba(255, 215, 0, 0.3);
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

/* 响应式设计 */
@media (max-width: 400px) {
    .iphone-container {
        width: 90vw;
        height: 80vh;
        max-width: 375px;
        max-height: 812px;
    }
}