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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.container {
    background: white;
    border-radius: 20px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    width: 100%;
    max-width: 500px;
    padding: 30px;
    animation: slideIn 0.5s ease-out;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(-30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

header {
    text-align: center;
    margin-bottom: 30px;
}

header h1 {
    color: #333;
    font-size: 28px;
    font-weight: 700;
}

.input-section {
    display: flex;
    gap: 10px;
    margin-bottom: 25px;
}

#memoInput {
    flex: 1;
    padding: 12px 16px;
    border: 2px solid #e0e0e0;
    border-radius: 10px;
    font-size: 16px;
    transition: all 0.3s ease;
    outline: none;
}

#memoInput:focus {
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.add-btn {
    padding: 12px 24px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 10px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    white-space: nowrap;
}

.add-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

.add-btn:active {
    transform: translateY(0);
}

.memo-list {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.memo-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 15px;
    background: #f8f9fa;
    border-radius: 10px;
    border-left: 4px solid #667eea;
    transition: all 0.3s ease;
    animation: fadeIn 0.3s ease-out;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateX(-20px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.memo-item:hover {
    background: #e9ecef;
    transform: translateX(5px);
}

.memo-text {
    flex: 1;
    color: #333;
    font-size: 16px;
    word-break: break-word;
}

.delete-btn {
    padding: 8px 16px;
    background: #ff6b6b;
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    white-space: nowrap;
    margin-left: 10px;
}

.delete-btn:hover {
    background: #ff5252;
    transform: scale(1.05);
}

.delete-btn:active {
    transform: scale(0.95);
}

.empty-state {
    text-align: center;
    padding: 40px 20px;
    color: #999;
    font-size: 16px;
    line-height: 1.6;
}

.empty-state.hidden {
    display: none;
}

/* 반응형 디자인 */
@media (max-width: 480px) {
    .container {
        padding: 20px;
    }

    header h1 {
        font-size: 24px;
    }

    .input-section {
        flex-direction: column;
    }

    .add-btn {
        width: 100%;
    }

    .memo-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 10px;
    }

    .delete-btn {
        width: 100%;
        margin-left: 0;
    }
}